Alek Davis: Technoblog

Why does Gmail clip messages?

2026-01-26T11:40:00.000-08:00

Summary: How to fix the Gmail clipping issue for localized email messages sent via SendGrid.

I dealt with this issue when working on two different projects. Spent several days figuring out the solution and fixed it for the first project. A few years passed. Ran into a similar problem, and totally forgot about the previous solution, so spent another few days addressing the same problem and later realized that I already addressed it before. Anyway, this is post primarily to myself in case I ran into the same problem again, but it may help other people.

PROBLEM

When my application sends email notifications, some of them appear as clipped in Gmail. The notifications are formatted as HTML and translated to various languages, but not all translation cause this issue. For example, notifications translated to German, Spanish, Finnish, French, Italian, Portuguese, and Swedish would be clipped, while translations to Arabic, Czech, Hebrew, Dutch, Japanese, Russian, Vietnamese and Chinese, would not (there are more languages in both lists). The notifications were about the same size (very short, just a few sentences), did not include any embedded media (and had just a small logo in the image reference tag). I checked multiple articles and none of the possible reasons causing message clipping applied to my notifications.

TROUBLESHOOTING

A while back, I had a similar issue caused by a copyright character. I use my own framework to generate email notification files from the templates and one of the third party libraries in the framework converted the HTML entities (such as ©) to the Unicode character equivalents (such as ©). At some point I added the capability to convert the Unicode characters back to the HTML entities, so it should have taken care of the problem, but I noticed that in the actual message in Gmail, the copyright character was again in Unicode. I will get back to it later, but since all my templates underwent the same process and all contained the same copyright message and some of them worked fine while others were clipped, it should not have been the issue (don't know if Gmail fixed it or something else happened by the Unicode copyright character I see in the email body now does not seem to cause clipping).

After spending many hours trying to isolate which particular characters cause message clipping, I noticed that the issue mostly affects accented characters. I wondered if the problem was caused by character sets. I downloaded the email messages from Gmail and noticed the discrepancy in the Content-Type header. The translated messages that were not clipped had the content type set to text/html; charset=utf-8, while the clipped messages were set to text/html; charset=iso-8859-1.

EXPLANATION

Here is what caused Gmail message clipping for me. We use SendGrid to send notifications, and their API (we use C#) does not allow specifying the content type character set. When we used the standard .NET messaging API, specifying the character set was trivial (and we did not have this problem), but for some reason, the SendGrid API does not support it. Instead, it tries to determine the most appropriate character set based on the message text. I do not know why they do it. Maybe it's a way to reduce message size or something else, but the bottom line is that there is no programmatic way to tell the API what character set to use when sending email messages. And I'm not sure about other clients, but Gmail is very particular about the content type it receives and the content of the message, so when it sees the ISO-8859-1 character set in the content type header, but notices accented characters, it clips the message, even if the message holds a single sentence (or word). I filed an issue with the SendGrid C# API about this (and another one for the HTML entities conversion), but something tells me that they will not fix it, so we need to find a solution.

SOLUTION

I'm not sure if there is a better way to address it, but the solution I picked was to include an invisible Unicode character in all message bodies to force SendGrid to set up content type character set to UTF-8. If you are having the same problem, add a line like this somewhere in the HTML email message body:

<!-- DO NOT REMOVE! KEEP THIS ELEMENT WITH THE ⌀ CHARACTER TO HELP SENDGRID USE UTF-8 ENCODING. -->
<span style="color: transparent; user-select: none; font-size: 0; display: none; visibility: hidden;">⌀</span>

I am using an HTML element with an invisible character instead of an HTML comment because some frameworks may remove comments before sending an email message to reduce the message size. So far, it solved my problem, and I do not see any clipping of any translation among the three dozen that we support. Now, the most important part is not to forget to do this in the next project.

OData! my Data!

2024-10-06T00:34:00.000-07:00

Summary: How to process OData filters in C#.

I spent a few days trying to figure out how to validate OData filte, so I'd like to share a piece of code that performs basic OData parsing. But before I get to code, let me explain what I'm doing here and why.

A typical use case could be a REST APIs built on top of ASP.NET Core (.NET 8) which talks to extrnal REST APIs that requires a consistent way for defining the search queries (or search filters) used by the HTTP GET operations. There are different ways to define search queries. For example, SCIM filtering spec looks simple and robust, but after spending the last decade dealing with SCIM implementations, I do not want to have anything to do with SCIM anymore.

The most reasonable option (other than building one from scratch) would be using OData. OData comes with a lot of goodies, but for our use case, we only needed to figure out how to parse and validate OData filters. I thought in .NET Core, handling OData queries would be simple, but unfortunately, the good people at Microsoft must have assumed that everyone using OData in their custom controllers would rely on entity frameworks, so they made it easy for the apps that integrate OData with their entity data models. Which is not what we do. In our case, we take a search query, validate it, and pass to an external API. What this API does with it, we do not care, but we want to be good citizens and not hand it garbage (and in case we get garbage from the clients, we want to send them meaningful errors explaining why their queries are garbage). To do this, we need to take an OData filter expression from a query string and make sure that it is valid. Should be simple, right?

There are many articles explaining how to integrate OData into the REST API controllers, but the only two posts I found useful for our use case were:

By trial and error, I built a simple program that validates and parses a string holding an OData filter. This program is not perfect (it does not handle all possible functions, operators, and complex scenarios), but for us, it is more than enough. I will make it more robust and implement the logic as a library at some point, but if you need a more or less simple example, showing how to validate and parse a not very complex OData filter, see code below (read the comments that explain the requirements and dependencies).

UPDATE: You can ignore the next section because I made a few improvements to the code and published both the library handling OData filters and the demo programs at GitHub (there is also a Nuget package available).

/*
This .NET Core console app was built and tested with the following Nuget packages {versions}:

- Microsoft.AspNetCore.OData {9.0.0}
- Microsoft.Extensions.DependencyInjection.Abstractions {8.0.1}
- Microsoft.OData.Core {8.0.1}

To install the latest versions of the packages, run from Package Manager Console:

Install-Package Microsoft.Extensions.DependencyInjection.Abstractions
Install-Package Microsoft.OData.Core
Install-Package Microsoft.AspNetCore.OData

SUMMARY:

This program illustrates how to validate and parse basic OData filters in the given text strings.
The code may not be comprehensive and it does not cover advanced OData use cases,
but it shows how to handle typical filter conditions that utilize common operations
and functions ('not', 'eq', 'ne', 'gt', 'ge', 'lt', 'le', 'startsWith', 'endsWith',
'contains', 'in') and grouped using logical operators ('and', 'or').

The filter properties will be mapped to properties of the filter object properties. The filter
objects (there is more than one) identify how OData filter attributes can be mapped to a real
entity that may come from an external resource, such as a web service, database, report, etc.
*/

// The following namespace holds the classes used in the OData filter.
#pragma warning disable IDE0130 // Namespace does not match folder structure
namespace TestOData1;
#pragma warning restore IDE0130 // Namespace does not match folder structure

using Microsoft.OData.Edm;
using Microsoft.OData.ModelBuilder;
using Microsoft.OData.UriParser;
using System.Linq;

/// <summary>
/// Main program.
/// </summary>
internal class Program
{
    #region Properties
    // Use the same separator for complex (nested) types as the OData filters.
    private static readonly string _separator = "/";

    // Number of indent characters for the binary tree output.
    private static readonly int _indentLength = 2;

    // Set this value to true to print object names of the tree nodes.
    private static readonly bool _printNode = false;
    #endregion

    #region Filter examples
    // Here are some basic filter we may want to test.

    // By default, property names are case-insensitive, but we'll make them case-insensitive.
    private static readonly string[] _filters =
    [
        "not(enabled)",
        "not(true)",
        "email eq null",
        "email ne null",
        "email eq 'john@mail.com'",
        "email ne 'john@mail.com'",
        "email eq displayName",
        "email ne displayName",
        "contains(email, '@')",
        "not contains(email, '@')",
        "contains(email, displayName)",
        "not contains(email, displayName)",
        "startsWith(email, 'john')",
        "not startsWith(email, 'john')",
        "endsWith(email, '@mail.com')",
        "not endsWith(email, '@mail.com')",
        "email in ('john@mail.com', 'mary@mail.com')",
        "not (email in ('john@mail.com', 'mary@mail.com'))",
        "id eq 0",
        "id gt 0",
        "id lt 2000",
        "id ge 1",
        "id le 2000",
        "name eq null",
        "name ne null",
        "name/givenName eq null",
        "sponsor/name/givenName eq null",
        "name/surname ne sponsor/name/surname",
        "name/givenName in ('John', 'Mary')",
        "name/givenName ne name/nickName",
        "startsWith(displayName, 'J')",
        "type eq 'Employee'",
        "type eq 'Guest' and name/Surname eq 'Johnson'",
        "type eq 'Contractor' and not(endsWith(email, '@mail.com'))",
        "enabled eq false and type in ('Employee', 'Contractor') ",
        "(enabled eq true and type eq 'Employee') or (enabled eq false and (type eq 'Guest' or endsWith(email, '@mail.com')))",
        "phoneNumbers/any(p: p eq '123-456-6789')",
        "socialLogins/any(s: s/name eq 'Facebook')",
        "socialLogins/any(s: s/name eq 'Facebook' or endsWith(s/url, 'google.com'))",
        "sponsor/phoneNumbers/any(p: p eq '123-456-6789')",
        "sponsor/socialLogins/any(s: s/name eq 'Facebook')"
    ];
    #endregion

    #region Main method
    private static void Main()
    {
        // The builder is responsible for mapping OData filter conditions to the object properties.
        ODataConventionModelBuilder builder = new();

        // UserFilter defines the properties which can be used in our filter (this class is defined below).
        // The UserFilter class properties also can be based on other complex types, but they will be
        // included implicitly, so no need to reference them.
        builder.AddEntityType(typeof(User));

        // EDM (Entity Data Model) encapsulates classes that will be used in the OData filters.
        IEdmModel model = builder.GetEdmModel();

        // Let's print all classes that our EDM schema recognizes.
        Console.WriteLine("ODATA SCHEMA ELEMENTS:");
        foreach (IEdmSchemaElement element in model.SchemaElements)
        {
            Console.WriteLine($"- {element.FullName()}: {element.SchemaElementKind}");
        }

        // If you define the EDM classes not under an explicitly defined namespace,
        // make sure you add 'Default.' to the full name because 'Default' would be the implicit
        // namespace created by the compiler; if you do not, these types will not be found.
        // string qualifiedName = "Default." + typeof(GroupFilter).FullName;
        string qualifiedName = typeof(User).FullName ?? "";

        // Now, lets use our filter class as the EDM type, so it can be used for OData filter handling.
        IEdmType type = model.FindDeclaredType(qualifiedName);
        if (type == null)
        {
            Console.WriteLine($"Type '{qualifiedName}' is not found in the OData schema model.");
            return;
        }

        foreach (string filter in _filters)
        {
            Console.WriteLine();
            Console.WriteLine(new string('-', 72));
            Console.WriteLine("EXPRESSION: " + filter);
            Console.WriteLine(new string('-', 72));

            // This dictionary can include other OData parameters,
            // such as "$top", "$skip", "$count", "$select", "$orderby", "$search", etc.
            // but we are only interested in the filter.
            Dictionary<string, string> options = new()
            {
                {"$filter", filter}
            };

            try
            {
                ODataQueryOptionParser parser = new(model, type, null, options)
                {
                    // By default, property names are case-sensitive,
                    // so we need to explicitly specify them to be case-insensitive.
                    Resolver = new ODataUriResolver() { EnableCaseInsensitive = true }
                };

                FilterClause clause = parser.ParseFilter();

                if (clause == null)
                {
                    Console.WriteLine("FilterClause is null.");
                }
                else
                {
                    ProcessNode(clause.Expression, 0, null);
                }
            }
            catch (Exception ex)
            {
                while (ex != null)
                {
                    Console.WriteLine(ex.Message + " ");

                    if (ex.InnerException != null)
                    {
                        ex = ex.InnerException;
                    }
                    else
                    {
                        break;
                    }
                }
                Console.WriteLine();
            }
        }
    }
    #endregion

    #region Node processing methods
    /// <summary>
    /// Process a node of the OData filter.
    /// </summary>
    /// <param name="node">
    /// Node to process.
    /// </param>
    /// <param name="level">
    /// Indent level of this node.
    /// </param>
    /// <param name="parentName">
    /// Name of the parent property of the nodes under the 'Any' operator.
    /// </param>
    /// <remarks>
    /// OData filter is basically a binary tree, so we'll process it as such.
    /// </remarks>
    private static void ProcessNode
    (
        SingleValueNode node, 
        int level, 
        string? parentName
    )
    {
        // The filter tree consists of nodes all of which are directly derived from SingleValueNode.
        if (node == null)
        {
            // Shouldn't happen, but just in case.
            return;
        }
        else if (node is BinaryOperatorNode binaryOperatorNode)
        {
            ProcessBinaryOperatorNode(binaryOperatorNode, level, parentName);
        }
        else if (node is SingleComplexNode singleComplexNode)
        {
            ProcessSingleComplexNode(singleComplexNode, level, parentName);
        }
        else if (node is SingleValueFunctionCallNode singleValueFunctionCallNode)
        {
            ProcessSingleValueFunctionCallNode(singleValueFunctionCallNode, level, parentName);
        }
        else if (node is SingleValueOpenPropertyAccessNode singleValueOpenPropertyAccessNode)
        {
            ProcessSingleValueOpenPropertyAccessNode(singleValueOpenPropertyAccessNode, level, parentName);
        }
        else if (node is SingleValuePropertyAccessNode singleValuePropertyAccessNode)
        {
            ProcessSingleValuePropertyAccessNode(singleValuePropertyAccessNode, level, parentName);
        }
        else if (node is InNode inNode)
        {
            ProcessInNode(inNode, level, parentName);
        }
        else if (node is ConstantNode constantNode)
        {
            ProcessConstantNode(constantNode, level);
        }
        else if (node is ConvertNode convertNode)
        {
            ProcessConvertNode(convertNode, level, parentName);
        }
        else if (node is UnaryOperatorNode unaryOperatorNode)
        {
            ProcessUnaryOperatorNode(unaryOperatorNode, level, parentName);
        }
        else if (node is AnyNode anyNode)
        {
            ProcessAnyNode(anyNode, level);
        }
        else if (node is NonResourceRangeVariableReferenceNode nonResourceRangeVariableReferenceNode)
        {
            ProcessNonResourceRangeVariableReferenceNode(nonResourceRangeVariableReferenceNode, level, parentName);
        }
        else
        {
            // There may be more node types that need to be handled explicitly,
            // but for now, let's handle all unexpected nodes as a simple node.
            ProcessSingleValueNode(node, level);
        }
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Handles all kinds of nodes, 
    /// e.g. holding elements that must be converted to a certain data type, such as enum,
    /// operator nodes, value nodes, etc.
    /// </summary>
    private static void ProcessConvertNode
    (
        ConvertNode node, 
        int level, 
        string? parentName
    )
    {
        ProcessNode(node.Source, level, parentName);
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="params"/>
    /// <summary>
    /// Handles the simplest node holding a single element.
    /// </summary>
    /// <remarks>
    /// This method will also handle any nodes that are not handled by the node type-specific methods.
    /// </remarks>
    private static void ProcessSingleValueNode
    (
        SingleValueNode node, 
        int level
    )
    {
        if (_printNode)
        {
            WriteLine(level, FormatNode(node.Kind));
        }
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Handles a node holding a simple constant value, such as a string, a number, or a boolean.
    /// </summary>
    private static void ProcessConstantNode
    (
        ConstantNode node, 
        int level
    )
    {
        WriteLine(level, FormatValue(node.Value ?? "(null)"));
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Handles values in the collection object (such as a collection inside of the 'in' clause).
    /// </summary>
    private static void ProcessCollectionConstantNode
    (
        CollectionConstantNode node, 
        int level, 
        string? parentName
    )
    {
        foreach(var value in node.Collection) 
        {
            ProcessNode(value, level, parentName);
        }
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Handles a node holding a complex (i.e. nested) object property.
    /// </summary>
    private static void ProcessSingleComplexNode
    (
        SingleComplexNode node, 
        int level,
        string? parentName
    )
    {
        WriteLine(level, FormatProperty(node.Property.Name));
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Handles a node holding a simple object property.
    /// </summary>
    private static void ProcessSingleValuePropertyAccessNode
    (
        SingleValuePropertyAccessNode node, 
        int level,
        string? parentName
    )
    {
        WriteLine(level, FormatProperty(GetPropertyName(node, parentName)));
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Not sure what node this is, but based on the name it should be similar to SingleValuePropertyAccessNode.
    /// </summary>
    private static void ProcessSingleValueOpenPropertyAccessNode
    (
        SingleValueOpenPropertyAccessNode node, 
        int level,
        string? parentName
    )
    {
        WriteLine(level, FormatProperty(GetPropertyName(node, parentName)));
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="params"/>
    /// <summary>
    /// Handles the nodes holding dynamic value such as aliases use in the 'Any' operator.
    /// </summary>
    private static void ProcessNonResourceRangeVariableReferenceNode
    (
        NonResourceRangeVariableReferenceNode node, 
        int level,
        string? parentName
    )
    {
        // In filter 'phoneNumbers/any(p: p eq '123-456-6789')', since 'p' is just an alias,
        // we want to print 'phoneNumbers' because it is the name of the collection to
        // to which the filter is applied.

        // This node should be under a parent's 'Any' operation.
        if (!string.IsNullOrEmpty(parentName))
        {
            WriteLine(level, FormatProperty(parentName));
        }
        // But just in case, we can just print the alias (e.g. 'p' in our example).
        else
        {
            WriteLine(level, FormatProperty(node.RangeVariable.Name));
        }
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Handles a unary operation node, such as 'not'.
    /// </summary>
    private static void ProcessUnaryOperatorNode
    (
        UnaryOperatorNode node, 
        int level,
        string? parentName
    )
    {
        ProcessSingleValueNode(node, level);

        WriteLine(level, FormatOperator(node.OperatorKind));

        ProcessNode(node.Operand, level + 1, parentName);
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Handles an any operation applicable to arrays, lists and collections.
    /// </summary>
    private static void ProcessAnyNode
    (
        AnyNode node, 
        int level
    )
    {
        ProcessSingleValueNode(node, level);

        WriteLine(level, FormatOperator(node.Kind));

        string? parentName = null;

        if (node.Source is CollectionPropertyAccessNode collectionPropertyAccessNode)
        {
            parentName = GetPropertyName(collectionPropertyAccessNode, null);
        }
        else if (node.Source is CollectionComplexNode collectionComplexNode)
        {
            parentName = GetPropertyName(collectionComplexNode, null);
        }

        if (!string.IsNullOrEmpty(parentName))
        {
            WriteLine(level + 1, FormatProperty(parentName));
            ProcessNode(node.Body, level + 2, parentName);
        }
        else
        {
            ProcessNode(node.Body, level + 1, null);
        }
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Handles a node holing an 'in' operation.
    /// </summary>
    private static void ProcessInNode
    (
        InNode node, 
        int level, 
        string? parentName
    )
    {
        ProcessSingleValueNode(node, level);

        WriteLine(level, FormatOperator(node.Kind));

        // The left element of the in node holds the property name.
        if (node.Left is SingleValuePropertyAccessNode singleValuePropertyAccessNode && 
            !string.IsNullOrEmpty(singleValuePropertyAccessNode.Property?.Name))
        {
            WriteLine(level + 1, FormatProperty(GetPropertyName(singleValuePropertyAccessNode.Property?.Name ?? "", parentName)));
        }
        else if (node.Left is SingleValueOpenPropertyAccessNode singleValueOpenPropertyAccessNode && 
            !string.IsNullOrEmpty(singleValueOpenPropertyAccessNode.Name))
        {
            WriteLine(level + 1, FormatProperty(GetPropertyName(singleValueOpenPropertyAccessNode.Name ?? "", parentName)));
        }

        // The right element of the in node holds the collection of the values. 
        if (node.Right is CollectionConstantNode collectionConstantNode)
        {
            ProcessCollectionConstantNode(collectionConstantNode, level + 1, parentName);
        }
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Handles a node holding a function call, such as 'startsWith', 'contains', etc.
    /// </summary>
    private static void ProcessSingleValueFunctionCallNode
    (
        SingleValueFunctionCallNode node, 
        int level, 
        string? parentName
    )
    {
        ProcessSingleValueNode(node, level);

        WriteLine(level, FormatOperator(node.Name));

        // The first item in the array of parameters holds the property being used in the function.
        if (node.Parameters.FirstOrDefault() is SingleValuePropertyAccessNode param)
        {
            WriteLine(level + 1, FormatProperty(GetPropertyName(param.Property.Name, parentName)));
        }

        // The rest of the items must be constants.
        IEnumerable<QueryNode> values = node.Parameters.Skip(1);

        foreach (QueryNode value in values) 
        {
            if (value is SingleValueNode singleValue)
            {
                ProcessNode(singleValue, level + 1, parentName);
            }
        }
    }

    /// <inheritdoc cref="ProcessNode(SingleValueNode, int, string?)" path="param"/>
    /// <summary>
    /// Handles a binary operator, such as 'eq', 'ne', 'and', 'or', etc.
    /// </summary>
    private static void ProcessBinaryOperatorNode
    (
        BinaryOperatorNode node, 
        int level, 
        string? parentName
    )
    {
        ProcessSingleValueNode(node, level);

        WriteLine(level, FormatOperator(node.OperatorKind));

        ProcessNode(node.Left, level + 1, parentName);
        ProcessNode(node.Right, level + 1, parentName);
    }
    #endregion

    #region Property name formatting methods
    /// <summary>
    /// Appends name of the parent to the given name if needed.
    /// </summary>
    /// <param name="name">
    /// Name of the property.
    /// </param>
    /// <param name="parentName">
    /// Name of the parent collection property (to which the 'Any' operation is applied).
    /// </param>
    /// <returns>
    /// Property name.
    /// </returns>
    private static string GetPropertyName
    (
        string name,
        string? parentName
    )
    {
        return string.IsNullOrEmpty(parentName)
            ? name
            : parentName + _separator + name;
    }

    /// <inheritdoc cref="GetPropertyName(string, string)" path="param|returns"/>
    /// <summary>
    /// Generates the name of the complex (i.e. nested) property that includes the names of all parents.
    /// </summary>
    /// <param name="node">
    /// Property node.
    /// </param>
    private static string GetPropertyName
    (
        SingleValuePropertyAccessNode node,
        string? parentName
    )
    {
        string path = "";
        string parent;

        if (node.Source == null)
        {
            return GetPropertyName(node.Property.Name, parentName);
        }

        // The source property point to the parent object referencing this property.
        var source = node.Source;

        while (source != null)
        {
            // There may be a couple of types used as sources.
            // In our example, UserFilter.Name is a SingleComplexNode, 
            // while UserFilter.Sponsor.Name is a SingleNavigationNode.
            // There may be other case, but I'm not sure how to test.
            if (source is SingleComplexNode singleComplexNode &&
                !string.IsNullOrEmpty(singleComplexNode.Property?.Name))
            {
                parent = singleComplexNode.Property.Name ?? "";
                source = singleComplexNode.Source;
            }
            else if (source is SingleNavigationNode singleNavigationNode &&
                !string.IsNullOrEmpty(singleNavigationNode.NavigationProperty?.Name))
            {
                parent = singleNavigationNode.NavigationProperty?.Name ?? "";
                source = singleNavigationNode.Source;
            }
            else
            {
                break;
            }

            path = string.IsNullOrEmpty(path)
                ? parent
                : parent + _separator + path;
        }

        return string.IsNullOrEmpty(path)
            ? GetPropertyName(node.Property.Name, parentName)
            : GetPropertyName(GetPropertyName(node.Property.Name, path), parentName);
    }

    /// <inheritdoc cref="GetPropertyName(SingleValuePropertyAccessNode, string)" path="param|returns"/>
    private static string GetPropertyName
    (
        SingleValueOpenPropertyAccessNode node,
        string? parentName
    )
    {
        string path = "";
        string parent;

        if (node.Source == null)
        {
            return GetPropertyName(node.Name, parentName);
        }

        // The source property point to the parent object referencing this property.
        var source = node.Source;

        while (source != null)
        {
            // There may be a couple of types used as sources.
            // In our example, UserFilter.Name is a SingleComplexNode, 
            // while UserFilter.Sponsor.Name is a SingleNavigationNode.
            // There may be other case, but I'm not sure how to test.
            if (source is SingleComplexNode singleComplexNode &&
                !string.IsNullOrEmpty(singleComplexNode.Property?.Name))
            {
                parent = singleComplexNode.Property.Name ?? "";
                source = singleComplexNode.Source;
            }
            else if (source is SingleNavigationNode singleNavigationNode &&
                !string.IsNullOrEmpty(singleNavigationNode.NavigationProperty?.Name))
            {
                parent = singleNavigationNode.NavigationProperty?.Name ?? "";
                source = singleNavigationNode.Source;
            }
            else
            {
                break;
            }

            path = string.IsNullOrEmpty(path)
                ? parent
                : parent + _separator + path;
        }

        return string.IsNullOrEmpty(path)
            ? GetPropertyName(node.Name, parentName)
            : GetPropertyName(GetPropertyName(node.Name, path), parentName);
    }

    /// <inheritdoc cref="GetPropertyName(SingleValuePropertyAccessNode, string)" path="param|returns"/>
    private static string GetPropertyName
    (
        CollectionComplexNode node,
        string? parentName
    )
    {
        string path = "";
        string parent;

        if (node.Source == null)
        {
            return GetPropertyName(node.Property.Name, parentName);
        }

        // The source property point to the parent object referencing this property.
        var source = node.Source;

        while (source != null)
        {
            // There may be a couple of types used as sources.
            // In our example, UserFilter.Name is a SingleComplexNode, 
            // while UserFilter.Sponsor.Name is a SingleNavigationNode.
            // There may be other case, but I'm not sure how to test.
            if (source is SingleComplexNode singleComplexNode &&
                !string.IsNullOrEmpty(singleComplexNode.Property?.Name))
            {
                parent = singleComplexNode.Property.Name ?? "";
                source = singleComplexNode.Source;
            }
            else if (source is SingleNavigationNode singleNavigationNode &&
                !string.IsNullOrEmpty(singleNavigationNode.NavigationProperty?.Name))
            {
                parent = singleNavigationNode.NavigationProperty?.Name ?? "";
                source = singleNavigationNode.Source;
            }
            else
            {
                break;
            }

            path = string.IsNullOrEmpty(path)
                ? parent
                : parent + _separator + path;
        }

        return string.IsNullOrEmpty(path)
            ? GetPropertyName(node.Property.Name, parentName)
            : GetPropertyName(GetPropertyName(node.Property.Name, path), parentName);
    }

    /// <inheritdoc cref="GetPropertyName(SingleValuePropertyAccessNode, string)" path="param|returns"/>
    private static string GetPropertyName
    (
        CollectionPropertyAccessNode node,
        string? parentName
    )
    {
        string path = "";
        string parent;

        if (node.Source == null)
        {
            return GetPropertyName(node.Property.Name, parentName);
        }

        // The source property point to the parent object referencing this property.
        var source = node.Source;

        while (source != null)
        {
            // There may be a couple of types used as sources.
            // In our example, UserFilter.Name is a SingleComplexNode, 
            // while UserFilter.Sponsor.Name is a SingleNavigationNode.
            // There may be other case, but I'm not sure how to test.
            if (source is SingleComplexNode singleComplexNode &&
                !string.IsNullOrEmpty(singleComplexNode.Property?.Name))
            {
                parent = singleComplexNode.Property.Name ?? "";
                source = singleComplexNode.Source;
            }
            else if (source is SingleNavigationNode singleNavigationNode &&
                !string.IsNullOrEmpty(singleNavigationNode.NavigationProperty?.Name))
            {
                parent = singleNavigationNode.NavigationProperty?.Name ?? "";
                source = singleNavigationNode.Source;
            }
            else
            {
                break;
            }

            path = string.IsNullOrEmpty(path)
                ? parent
                : parent + _separator + path;
        }

        return string.IsNullOrEmpty(path)
            ? GetPropertyName(node.Property.Name, parentName)
            : GetPropertyName(GetPropertyName(node.Property.Name, path), parentName);
    }

    #endregion
    
    #region Output formatting methods
    /// <summary>
    /// Formats node message.
    /// </summary>
    /// <param name="name">
    /// Name of the node.
    /// </param>
    /// <returns>
    /// Formatted node message.
    /// </returns>
    private static string FormatNode
    (
        object name
    )
    {
        return "NODE: " + name;
    }

    /// <summary>
    /// Formats operator message.
    /// </summary>
    /// <param name="name">
    /// Name of the operator.
    /// </param>
    /// <returns>
    /// Formatted operator message.
    /// </returns>
    private static string FormatOperator
    (
        object name
    )
    {
        return "OPERATOR: " + name;
    } 

    /// <summary>
    /// Formats property message.
    /// </summary>
    /// <param name="name">
    /// Name of the property.
    /// </param>
    /// <returns>
    /// Formatted property message.
    /// </returns>
    private static string FormatProperty
    (
        object name
    )
    {
        return "PROPERTY: " + name;
    }

    /// <summary>
    /// Formats value message.
    /// </summary>
    /// <param name="name">
    /// Name of the value.
    /// </param>
    /// <returns>
    /// Formatted value message.
    /// </returns>
    private static string FormatValue
    (
        object name
    )
    {
        return "VALUE: " + name;
    }
    #endregion

    #region Print functions
    /// <summary>
    /// Prints text with appropriate indentation.
    /// </summary>
    /// <param name="indentLevel">
    /// Indentation level.
    /// </param>
    /// <param name="message">
    /// Message text.
    /// </param>
    /// <param name="args">
    /// Optional message parameters.
    /// </param>
    private static void WriteLine
    (
        int indentLevel, 
        string message, 
        params object[] args
    )
    {
        string indent = new(' ', indentLevel * _indentLength);
        Console.WriteLine(indent + message, args);
    }
    #endregion
}

#region Data models used by the OData filter
/// <summary>
/// Defines types of users.
/// </summary>
public enum UserType
{
    Employee,
    Contractor,
    Guest
}

/// <summary>
/// Defines name parts.
/// </summary>
public class PersonName
{
    public string? GivenName
    {
        get; set;
    }

    public string? NickName
    {
        get; set;
    }

    public string? Surname
    {
        get; set;
    }

    public char? MiddleInitial
    {
        get; set;
    }
}

/// <summary>
/// Defines social login info.
/// </summary>
public class SocialLogin
{
    public string? Name
    {
        get; set;
    }

    public string? Url
    {
        get; set;
    }
}

/// <summary>
/// Primary filter object (it may not necessarily correspond to the corresponding backend entity).
/// </summary>
public class User
{
    public int? Id
    {
        get; set;
    }

    public UserType? Type
    {
        get; set;
    }

    public PersonName? Name
    {
        get; set;
    }

    public string? DisplayName
    {
        get; set;
    }

    public string? Email
    {
        get; set;
    }

    public bool? Enabled
    {
        get; set;
    }

    // Use this property to test complex properties (it can be nested indefinitely).
    public User? Sponsor
    {
        get; set;
    }

    public string[]? PhoneNumbers
    {
        get; set;
    }

    public List<SocialLogin>? SocialLogins
    {
        get; set;
    }
}
#endregion

Here is the program output:

ODATA SCHEMA ELEMENTS:
- TestOData1.User: TypeDefinition
- TestOData1.PersonName: TypeDefinition
- TestOData1.SocialLogin: TypeDefinition
- TestOData1.UserType: TypeDefinition
- Default.Container: EntityContainer

------------------------------------------------------------------------
EXPRESSION: not(enabled)
------------------------------------------------------------------------
OPERATOR: Not
  PROPERTY: Enabled

------------------------------------------------------------------------
EXPRESSION: not(true)
------------------------------------------------------------------------
OPERATOR: Not
  VALUE: True

------------------------------------------------------------------------
EXPRESSION: email eq null
------------------------------------------------------------------------
OPERATOR: Equal
  PROPERTY: Email
  VALUE: (null)

------------------------------------------------------------------------
EXPRESSION: email ne null
------------------------------------------------------------------------
OPERATOR: NotEqual
  PROPERTY: Email
  VALUE: (null)

------------------------------------------------------------------------
EXPRESSION: email eq 'john@mail.com'
------------------------------------------------------------------------
OPERATOR: Equal
  PROPERTY: Email
  VALUE: john@mail.com

------------------------------------------------------------------------
EXPRESSION: email ne 'john@mail.com'
------------------------------------------------------------------------
OPERATOR: NotEqual
  PROPERTY: Email
  VALUE: john@mail.com

------------------------------------------------------------------------
EXPRESSION: email eq displayName
------------------------------------------------------------------------
OPERATOR: Equal
  PROPERTY: Email
  PROPERTY: DisplayName

------------------------------------------------------------------------
EXPRESSION: email ne displayName
------------------------------------------------------------------------
OPERATOR: NotEqual
  PROPERTY: Email
  PROPERTY: DisplayName

------------------------------------------------------------------------
EXPRESSION: contains(email, '@')
------------------------------------------------------------------------
OPERATOR: contains
  PROPERTY: Email
  VALUE: @

------------------------------------------------------------------------
EXPRESSION: not contains(email, '@')
------------------------------------------------------------------------
OPERATOR: Not
  OPERATOR: contains
    PROPERTY: Email
    VALUE: @

------------------------------------------------------------------------
EXPRESSION: contains(email, displayName)
------------------------------------------------------------------------
OPERATOR: contains
  PROPERTY: Email
  PROPERTY: DisplayName

------------------------------------------------------------------------
EXPRESSION: not contains(email, displayName)
------------------------------------------------------------------------
OPERATOR: Not
  OPERATOR: contains
    PROPERTY: Email
    PROPERTY: DisplayName

------------------------------------------------------------------------
EXPRESSION: startsWith(email, 'john')
------------------------------------------------------------------------
OPERATOR: startswith
  PROPERTY: Email
  VALUE: john

------------------------------------------------------------------------
EXPRESSION: not startsWith(email, 'john')
------------------------------------------------------------------------
OPERATOR: Not
  OPERATOR: startswith
    PROPERTY: Email
    VALUE: john

------------------------------------------------------------------------
EXPRESSION: endsWith(email, '@mail.com')
------------------------------------------------------------------------
OPERATOR: endswith
  PROPERTY: Email
  VALUE: @mail.com

------------------------------------------------------------------------
EXPRESSION: not endsWith(email, '@mail.com')
------------------------------------------------------------------------
OPERATOR: Not
  OPERATOR: endswith
    PROPERTY: Email
    VALUE: @mail.com

------------------------------------------------------------------------
EXPRESSION: email in ('john@mail.com', 'mary@mail.com')
------------------------------------------------------------------------
OPERATOR: In
  PROPERTY: Email
  VALUE: john@mail.com
  VALUE: mary@mail.com

------------------------------------------------------------------------
EXPRESSION: not (email in ('john@mail.com', 'mary@mail.com'))
------------------------------------------------------------------------
OPERATOR: Not
  OPERATOR: In
    PROPERTY: Email
    VALUE: john@mail.com
    VALUE: mary@mail.com

------------------------------------------------------------------------
EXPRESSION: id eq 0
------------------------------------------------------------------------
OPERATOR: Equal
  PROPERTY: Id
  VALUE: 0

------------------------------------------------------------------------
EXPRESSION: id gt 0
------------------------------------------------------------------------
OPERATOR: GreaterThan
  PROPERTY: Id
  VALUE: 0

------------------------------------------------------------------------
EXPRESSION: id lt 2000
------------------------------------------------------------------------
OPERATOR: LessThan
  PROPERTY: Id
  VALUE: 2000

------------------------------------------------------------------------
EXPRESSION: id ge 1
------------------------------------------------------------------------
OPERATOR: GreaterThanOrEqual
  PROPERTY: Id
  VALUE: 1

------------------------------------------------------------------------
EXPRESSION: id le 2000
------------------------------------------------------------------------
OPERATOR: LessThanOrEqual
  PROPERTY: Id
  VALUE: 2000

------------------------------------------------------------------------
EXPRESSION: name eq null
------------------------------------------------------------------------
OPERATOR: Equal
  PROPERTY: Name
  VALUE: (null)

------------------------------------------------------------------------
EXPRESSION: name ne null
------------------------------------------------------------------------
OPERATOR: NotEqual
  PROPERTY: Name
  VALUE: (null)

------------------------------------------------------------------------
EXPRESSION: name/givenName eq null
------------------------------------------------------------------------
OPERATOR: Equal
  PROPERTY: Name/GivenName
  VALUE: (null)

------------------------------------------------------------------------
EXPRESSION: sponsor/name/givenName eq null
------------------------------------------------------------------------
OPERATOR: Equal
  PROPERTY: Sponsor/Name/GivenName
  VALUE: (null)

------------------------------------------------------------------------
EXPRESSION: name/surname ne sponsor/name/surname
------------------------------------------------------------------------
OPERATOR: NotEqual
  PROPERTY: Name/Surname
  PROPERTY: Sponsor/Name/Surname

------------------------------------------------------------------------
EXPRESSION: name/givenName in ('John', 'Mary')
------------------------------------------------------------------------
OPERATOR: In
  PROPERTY: GivenName
  VALUE: John
  VALUE: Mary

------------------------------------------------------------------------
EXPRESSION: name/givenName ne name/nickName
------------------------------------------------------------------------
OPERATOR: NotEqual
  PROPERTY: Name/GivenName
  PROPERTY: Name/NickName

------------------------------------------------------------------------
EXPRESSION: startsWith(displayName, 'J')
------------------------------------------------------------------------
OPERATOR: startswith
  PROPERTY: DisplayName
  VALUE: J

------------------------------------------------------------------------
EXPRESSION: type eq 'Employee'
------------------------------------------------------------------------
OPERATOR: Equal
  PROPERTY: Type
  VALUE: Employee

------------------------------------------------------------------------
EXPRESSION: type eq 'Guest' and name/Surname eq 'Johnson'
------------------------------------------------------------------------
OPERATOR: And
  OPERATOR: Equal
    PROPERTY: Type
    VALUE: Guest
  OPERATOR: Equal
    PROPERTY: Name/Surname
    VALUE: Johnson

------------------------------------------------------------------------
EXPRESSION: type eq 'Contractor' and not(endsWith(email, '@mail.com'))
------------------------------------------------------------------------
OPERATOR: And
  OPERATOR: Equal
    PROPERTY: Type
    VALUE: Contractor
  OPERATOR: Not
    OPERATOR: endswith
      PROPERTY: Email
      VALUE: @mail.com

------------------------------------------------------------------------
EXPRESSION: enabled eq false and type in ('Employee', 'Contractor')
------------------------------------------------------------------------
OPERATOR: And
  OPERATOR: Equal
    PROPERTY: Enabled
    VALUE: False
  OPERATOR: In
    PROPERTY: Type
    VALUE: Employee
    VALUE: Contractor

------------------------------------------------------------------------
EXPRESSION: (enabled eq true and type eq 'Employee') or (enabled eq false and (type eq 'Guest' or endsWith(email, '@mail.com')))
------------------------------------------------------------------------
OPERATOR: Or
  OPERATOR: And
    OPERATOR: Equal
      PROPERTY: Enabled
      VALUE: True
    OPERATOR: Equal
      PROPERTY: Type
      VALUE: Employee
  OPERATOR: And
    OPERATOR: Equal
      PROPERTY: Enabled
      VALUE: False
    OPERATOR: Or
      OPERATOR: Equal
        PROPERTY: Type
        VALUE: Guest
      OPERATOR: endswith
        PROPERTY: Email
        VALUE: @mail.com

------------------------------------------------------------------------
EXPRESSION: phoneNumbers/any(p: p eq '123-456-6789')
------------------------------------------------------------------------
OPERATOR: Any
  PROPERTY: PhoneNumbers
    OPERATOR: Equal
      PROPERTY: PhoneNumbers
      VALUE: 123-456-6789

------------------------------------------------------------------------
EXPRESSION: socialLogins/any(s: s/name eq 'Facebook')
------------------------------------------------------------------------
OPERATOR: Any
  PROPERTY: SocialLogins
    OPERATOR: Equal
      PROPERTY: SocialLogins/Name
      VALUE: Facebook

------------------------------------------------------------------------
EXPRESSION: socialLogins/any(s: s/name eq 'Facebook' or endsWith(s/url, 'google.com'))
------------------------------------------------------------------------
OPERATOR: Any
  PROPERTY: SocialLogins
    OPERATOR: Or
      OPERATOR: Equal
        PROPERTY: SocialLogins/Name
        VALUE: Facebook
      OPERATOR: endswith
        PROPERTY: SocialLogins/Url
        VALUE: google.com

------------------------------------------------------------------------
EXPRESSION: sponsor/phoneNumbers/any(p: p eq '123-456-6789')
------------------------------------------------------------------------
OPERATOR: Any
  PROPERTY: Sponsor/PhoneNumbers
    OPERATOR: Equal
      PROPERTY: Sponsor/PhoneNumbers
      VALUE: 123-456-6789

------------------------------------------------------------------------
EXPRESSION: sponsor/socialLogins/any(s: s/name eq 'Facebook')
------------------------------------------------------------------------
OPERATOR: Any
  PROPERTY: Sponsor/SocialLogins
    OPERATOR: Equal
      PROPERTY: Sponsor/SocialLogins/Name
      VALUE: Facebook

Enjoy!

Customizing .editorconfig file

2024-05-01T13:19:00.000-07:00

Summary: A few non-default settings in the .editorconfig file that will improve the code.

Before checking in code updates, I prefer the compiler output (and the Visual Studio Error List tab) to show no errors (obviously) or warnings. In most cases, the warnings are useful (I learned a few programming trick from some), but some (mostly, IntelliSense) warnings are a bit irritating, so I prefer to supress them. To allow my warning supression settings to be shared across the team, I put them in the .editorconfig file, which gets saved in the source control along with the project. The following settings override the defaults:

# Expression-level preferences
csharp_style_unused_value_expression_statement_preference = unused_local_variable:none

# Primary constructors (mess up XML comment-based docs)
csharp_style_prefer_primary_constructors = false:suggestion

# Indentation preferences
csharp_indent_labels = flush_left

# IDE0058: Expression value is never used
dotnet_diagnostic.IDE0058.severity = silent

Unit testing cheat sheet (xUnit, FakeItEasy, FluentAssertions)

2024-02-11T00:02:00.000-08:00

Summary: Samples of C# code handling common unit testing tasks using xUnit, FakeItEasy, and FluentAssertions frameworks.

Here are some tips, samples, and suggestions for implementing common unit testing tasks.

Unit test without parameters:

[Fact]
void SampleClassName_MethodToBeTested_DescriptiveTestTitle()
{
    // ARRANGE
    // ACT
    // ASSERT
}

Unit test with parameters:

[Theory]
[InlineData("abc", 1, true)]
[InlineData("xyz", 2, false)]
void SampleClassName_MethodToBeTested_DescriptiveTestTitle
(
    string? param1,
    int? param2,
    bool? param3
)
{
    // ARRANGE
    // ACT
    // ASSERT
}

Unit tests with DateTime or DateTimeOffset parameters:

[Theory]
[InlineData("2024-06-05 23:45:10.456", "3/28/2007 12:13:50 PM -07:00")]
void SampleClassName_MethodToBeTested_DescriptiveTestTitle
(
    string? paramDateTime,
    string? paramDateTimeOffset
)
{
    DateTime dateTime = DateTime.Parse(paramDateTime);
    DateTime dateTimeOffset = DateTimeOffset.Parse(paramDateTimeOffset);
    ...
}

Unit tests with complex parameters:

[Theory]
[InlineData("{\"id\":123,\"email\":\"joe.doe@somemail.com\",\"enabled\":true}")]
void SampleClassName_MethodToBeTested_DescriptiveTestTitle
(
    string? paramUser
)
{
	// This example uses Newtonsoft.Json, but the same can be done
    // using the default framework's JSON serializer.
    User? user = JsonConvert.DeserializeObject<User?>(paramUser);
    
    // NOTE: Yes, I know about MemberData, but this seems more straightforward IMHO.
    ...
}

A fake object with the default constructor (can use an interface or a class):

ISample fakeISample = A.Fake<ISample>();
Sample fakeSample = A.Fake<Sample>();
ISample<AnotherSample> fakeGenericSample = A.Fake<ISample<AnotherSample>>();

A fake object with a parametrized constructor:

Sample fakeSample = A.Fake<Sample>(x => x.WithArgumentsForConstructor(new object[] { "param1", 2, true }));

A fake object returns specific property values:

User user = A.Fake<User>();

A.CallTo(() => user.Id).Returns(12345);
A.CallTo(() => user.Email).Returns("joe.doe@somemail.com");
A.CallTo(() => user.Enabled).Returns(true);

A fake object returns a specific method result:

// Data service is used by user service to get user from database
// and we are faking it.
IDataService dataService = A.Fake<IDataService>();

// Define properties of the user object to be retuned.
int id = 12345;

// Let's assume that the method of the UserService class being tested 
// internally calls the GetUserById method of the IDataService object
// (we're using a fake here to simulate a valid return).
A.CallTo(() => dataService.GetUserById(id)).Returns(new User(id));

// UserService is the class we're testing (system under test or SUT).
UserService userService = new UserService(dataService);

// We are testing the Enable method and expect it to be successful.
userService.Enable(id);

Use wildcard to trigger a fake method result for any parameter value:

// A<T>._ is a shortcut for a wildcard.
A.CallTo(() => dataService.GetUserById(A<string>._)).Returns(existingUser);

A fake object returns a specific value from an async method:

IDataService dataService = A.Fake<IDataService>();

// Define properties of the user object to be retuned.
int id = 12345;

// Assume that GetUserById is an async method returning Task<User>.
A.CallTo(() => dataService.GetUserById(A<string>._)).Returns(Task.FromResult(new User(id)));

A fake object returns a specific value from a generic method:

// Data service is used by user service to get user from database
// and we are faking it.
IDataService dataService = A.Fake<IDataService>();

// Define properties of the user object to be retuned.
int id = 12345;

// Data service has a generic method GetUser that we want to fake.
A.CallTo(dataService).Where(call => call.Method.Name == "GetUser")
   .WithReturnType<User>()
   .Returns(new User(id));
   
// UserService is the class we're testing (system under test or SUT).
UserService userService = new UserService(dataService);

Force a fake method to throw an exception:

A.CallTo(() => dataService.GetUserById(A<string>._)).Throws<Exception>();
// Equivalent to:
A.CallTo(() => dataService.GetUserById(A<string>._)).Throws(new Exception());

Expect a method to throw an exception of the exact type:

Assert.Throws<InvalidInputException>(() => userService.UpdateUser(user));

Expect a method to throw any exception derived from the specific type:

Assert.ThrowsAny<InvalidInputException>(() => userService.UpdateUser(user));

Assign expected exception to a variable:

Exception ex = Assert.Throws<InvalidInputException>(() => userService.UpdateUser(user));

Set up a fake SendGrid call:

ISendGridClient _sendGridClient = A.Fake<ISendGridClient>();

System.Net.Http.HttpResponseMessage httpResponse = new();
System.Net.Http.HttpContent         httpContent  = httpResponse.Content;
System.Net.Http.HttpResponseHeaders httpHeaders  = httpResponse.Headers;

httpHeaders.Add("X-Message-Id", "12345");

SendGrid.Response sendGridResponse = 
    A.Fake<SendGrid.Response>(x => x
        .WithArgumentsForConstructor(new object[] { httpStatusCode, httpContent, httpHeaders }));

A.CallTo(() =< _sendGridClient
    .SendEmailAsync(A<SendGridMessage>._, A<CancellationToken>._))
    .Returns(Task.FromResult(sendGridResponse));

Mock HttpContext for a controller class under test:

System.Net.Http.HttpRequest httpRequest = A.Fake<HttpRequest>();
System.Net.Http.HttpContext httpContext= A.Fake<HttpContext>();

A.CallTo(() => httpContext.Request).Returns(httpRequest);

// Set up the request properies that you need.
A.CallTo(() => httpRequest.Scheme).Returns("https");
A.CallTo(() => httpRequest.Host).Returns(new HostString("localhost:8888"));
A.CallTo(() => httpRequest.PathBase).Returns(new PathString("/api/v1"));
A.CallTo(() => httpRequest.Path).Returns(new PathString("sample"));
A.CallTo(() => httpRequest.QueryString).Returns(new QueryString("?a=b&c=d"));
 
// SampleController is derived from the ControllerBase class.
SampleController controller = new(...);

controller.ControllerContext =  new ControllerContext()
{
	HttpContext = httpContext
};

Controller method GET returns HTTP status code 200 OK:

// Assume that all dependencies have been set.
ActionResult<User> actionResult = controller.GetUser("1234567890");

// First, test action result.
actionResult.Should().NotBeNull();
actionResult.Result.Should().NotBeNull();
actionResult.Result.Should().BeAssignableTo<OkObjectResult>();

// Next, test response specific result.
OkObjectResult? result = actionResult.Result as OkObjectResult;

Controller method POST returns HTTP status code 201 Created:

// Assume that all dependencies have been set.
ActionResult<User> actionResult = controller.CreateUser(user);

// First, test action result.
actionResult.Should().NotBeNull();
actionResult.Result.Should().NotBeNull();
actionResult.Result.Should().BeAssignableTo<CreatedResult>();

// Next, test response specific result.
CreatedResult? result = actionResult.Result as CreatedResult;
result.Should().NotBeNull();

// Successful POST must return the URL of the GET method 
// ending with the ID of the newly created object in the
// Location header.
result?.Location.Should().NotBeNull();
result?.Location.Should().EndWith(id);

Controller method PATCH returns HTTP status code 204 No Content:

// Assume that all dependencies have been set.
ActionResult actionResult = controller.UpdateUser(user);

// First, test action result.
actionResult.Should().NotBeNull();
actionResult.BeAssignableTo<NoContentResult>();

Controller method POST returns HTTP status code 400 Bad Request:

// Assume that all dependencies have been set.
ActionResult<User> actionResult = controller.CreateUser(user);

// First, test action result.
actionResult.Should().NotBeNull();
actionResult.Result.Should().NotBeNull();
actionResult.Result.Should().BeAssignableTo<BadRequestObjectResult>();

// Next, test response specific result.
BadRequestObjectResult? result = actionResult.Result as BadRequestObjectResult;
result.Should().NotBeNull();

// Finally, check the error object to be returned to consumer.
// This example shows a custom problem details object ErroDetails,
// which may be different in your case.
result?.Value.Should().NotBeNull();
result?.Value.Should().BeAssignableTo<ErrorDetails>();

if (result?.Value is ErrorDetails errorDetails)
{
    // ServiceCodeType is a custom enum value returned via the error object's 
    // ServiceCode property (this check may be different in your case).
    errorDetails.ServiceCode.Should().NotBeNull();  
    errorDetails.ServiceCode.Should().Be(ServiceCodeType.BadRequest.ToString());
}

Controller method POST returns HTTP status code 401 Unauthorized:

// Assume that all dependencies have been set.
ActionResult<User> actionResult = controller.CreateUser(user);

// First, test action result.
actionResult.Should().NotBeNull();
actionResult.Result.Should().NotBeNull();
actionResult.Result.Should().BeAssignableTo<UnauthorizedObjectResult>();

// Next, test response specific result.
UnauthorizedObjectResult? result = actionResult.Result as UnauthorizedObjectResult;
result.Should().NotBeNull();

// See example handling 400 Bad Request.

Controller method PATCH returns HTTP status code 404 Not Found:

// Assume that all dependencies have been set.
ActionResult<User> actionResult = controller.UpdateUser(user);

// First, test action result.
actionResult.Should().NotBeNull();
actionResult.Result.Should().NotBeNull();
actionResult.Result.Should().BeAssignableTo<NotFoundObjectResult>();

// Next, test response specific result.
NotFoundObjectResult? result = actionResult.Result as NotFoundObjectResult;
result.Should().NotBeNull();

// See example handling 400 Bad Request.

Controller method POST returns HTTP status code 409 Conflict:

// Assume that all dependencies have been set.
ActionResult<User> actionResult = controller.CreateUser(user);

// First, test action result.
actionResult.Should().NotBeNull();
actionResult.Result.Should().NotBeNull();
actionResult.Result.Should().BeAssignableTo<ConflictObjectResult>();

// Next, test response specific result.
ConflictObjectResult? result = actionResult.Result as ConflictObjectResult;
result.Should().NotBeNull();

// See example handling 400 Bad Request.

Mock AppSettings:

// The following dictionary mimics appsettings.json file.
// Notice how array values must be defined using indexes.
Dictionary<string,string?> configSettings = new()
{
    {"ServiceA:ValueSettingX", "ValueX"},
    {"ServiceA:ValueSettingY", "ValueY"},
    {"ServiceA:ValueSettingZ", "ValueZ"},
    {"ServiceA:ArraySetting1:0", "Value0"},
    {"ServiceA:ArraySetting1:1", "Value1"},
    {"ServiceA:ArraySetting1:2", "Value2"},
}

IConfiguration config = new ConfigurationBuilder()
    .AddInMemoryCollection(configSettings)
    .Build();

Common FluentAssertions:

// Value should not be null.
value.Should().NotBeNull();

// Value should be of specific type.
value.Should().BeOfType<User>();

// Value should be equal to.
value.Should().Be(1);
value.Should().Be(true);
value.Should().Be("expected value");

// Value should contain (comparison is case sensitive).
value.Should().Contain("value");

// Value should contain any one of the specified values (comparison is case sensitive):
value.Should().ContainAny("value1", "value2");

// Value should contain all of the specified values (comparison is case sensitive):
value.Should().ContainAll("value1", "value2");

// String value should be equal to (comparison is case insensitive).
value.Should().BeEquivalentTo("Value");

How to edit a web page layout in the browser

2023-02-01T17:43:00.005-08:00

Summary: How to edit a web page in a browser.

Here is something my 10-year-old showed me that I used at work today. Since I do not do this often, it's mostly a note to self (in case I forget). If you need to play with a web page layout in a browser (I, for example, needed to add some new lines to a few messages on the page to see what makes them easier to read). It is very simple (the instructions assume you are using Google Chrome, but I suspect you can do the same in other browsers).

Right click anywehere on the web page and select the Inspect option from the context menu.
In the Developer Tools' window, switch to the Console tab.
At the prompt, type in document.body.contentEditable=true and press Enter.
Make your changes on the page (you can cadd, change and delete text, and do other things).
When done with your changes, at the prompt, type in document.body.contentEditable=false and press Enter

Happy programming.

Tell Git to bypass proxy for internal addresses

2022-06-27T12:02:00.007-07:00

Summary: How to make Git bypass proxy settings when connecting to internal repositories.

A common question enterprise application developers ask that generally gets unsatisfactory answers is: how do you configure Git to use the corporate proxy settings to connect to the external repositories (such as Github) while bypassing the proxy when connecting to internal repositories (such as corporate Gitlab instances)? A typical answer would recommend configuring proxy settings on each repo. The problem with this approach is that it assumes that you already have a local repo, but how do you access a repo if you want to perform the initial clone other than changing global proxy settings?

One option would be to specify proxy in the git clone command. For example, to bypass the global proxy settings, run it like this:

git -c http.proxy= clone https://internalgithub.com/foo/bar.git

But there is an even better solution: you can specify proxy settings on a per-domain basis. The following instructions assume that you are using a Windows system (I suspect that Mac or Linux instructions would be slightly different, but the idea must be the same). Simply, open the .gitconfig file located in the root of your user profile folder (such as c:\Windows\Users\yourusername), and add lines similar to the following:

[http]
	proxy = http://your.corp.proxy.server.com:XXX
	sslBackend = schannel
[https]
	proxy = http://your.corp.proxy.server.com:YYY
[http "https://your.company.repo.host1.com/"]
	proxy = ""
	sslVerify = false
[http "https://your.company.repo.host2.com/"]
	proxy = ""
	sslVerify = false
[credential "https://your.company.repo.host1.com/"]
	provider = generic
[credential "https://your.company.repo.host2.com/"]
	provider = generic

Once you save the .gitconfig file, you will need to log off and log on to the system for the changes to take effect.

Notice that your global proxy settings are defined under both the http and https sections, while domain-specific sections only use http (when I added the https sections for domain-specific URLs, it stopped working). Also, the global proxy definition assumes that the proxy server does not require authentication (if it does, adjust the proxy definition appropriately).

How to stop and start tracking file changes for Git

2022-05-05T14:00:00.008-07:00

Summary: Git commands that let you stop and start tracking project file chages.

During application development, there may be situations when you want to make a change in a file (e.g. modify an application setting) without accidentally committing this change to source control. There may be better ways to do this, but one option is to tell Git to stop tracking the file before you make the the change that you do not commit to the repo. Say, there is an appsettings.Developement.json file that you want to stop and start tracking. This is how I do it.

Create two files stop-tracking-appsettings.bat and start-tracking-appsettings.bat files in the solution folder (PROJECT_FOLDER must be replace by the name of the project directory under the solution folder).

stop-tracking-appsettings.bat

@echo off
git update-index --skip-worktree PROJECT_FOLDER\appsettings.Development.json

start-tracking-appsettings.bat

@echo off
git update-index --no-skip-worktree PROJECT_FOLDER\appsettings.Development.json

Now you can either run these files from a console whenever you want to stop and start tracking file changes. Even better, in Visual Studio, you can create a custom tool menu option (e.g. Run batch file) that you can invoke by right clicking the file in the Solution Explorer and selectin the context menu option (see this Stack Overflow answer explaining how to set it up).

Resources that helped me pass the CISSP exam

2021-10-21T12:01:00.167-07:00

Summary: List of helpful resources for CISSP exam.

After four months of intense study (and about a year since I started) I passed the CISSP exam. Here is the list of resources I found useful (and some that weren't).

BOOTCAMPS

Feedback from my colleagues who went to bootcamps varies but the general consensus is that with some exceptions they are not really worth the cost. There is only a handful of trainers who are exceptional and you can find them online for cheaper than $2K+. Yes, most bootcamps can give you a voucher to repeat an exam if you do not pass, but it's still cheaper to pay for two exams than for one bootcamp.

The digital versions of the bootcamps I used and found helpful include:

Thor's CISSP Udemy course. I have a Udemy subscription through work, so I watched this course 3 times: first, in the very beginning of my studies (and did not really like it), then after the 2021 update, and finally on the week of the exam at 2x speed (now, after watching it three times, I can say, it's excellent).
I lost the link but there was an old audio version of Kelly Handerhan's Cybrary course posted on Reddit. I watched a couple of video episodes when they were free at Cybrary, but mostly listened to the audio while driving. Overall, I think I listened to the whole series 2-3 times (at x1.7 speed). Kelly is one of (if not) the best instructors out there. The audio version is a bit outdated, but the fundamentals are still there. Highly recommend. Also, make sure you watch Kelly's Why You Will Pass the CISSP [exam] video. (UPDATE: Found links to the audios here.)
Destination Certification's Mind Map series. Excellent coverage. I would recommend also watching the supplemental videos, like the one that explains how Kerberos works and there are others.

BOOKS

I first planned to use O'Reilly Digital Subscription (through work), but the digital versions did not work for me, so I switched to paperbacks (for casual reading, I prefer digital).

(ISC)2 CISSP Certified Information Systems Security Professional Official Study Guide & Practice Tests Bundle. Only used as a reference. I started reading it but after two chapters realized it was too much for my average brain. I haven't used the practice tests because I bough the app (see below) and it covered the same questions.
CISSP for Dummies. Read a few chapters. It's OK.
Eleventh Hour CISSP: Study Guide Study Guide. Read once cover to cover. Highly recommend.
How To Think Like A Manager for the CISSP Exam. Good book to help you get into the right mindset.

PRACTICE TESTS

When practicing tests, the point is not to remember, but to try to understand why an answer is right or wrong. Yes you need to memorize a few things, but generally, memorization will not take you too far.

Boson Practice Exams. Must be used on a desktop (Windows, not sure it the environment works on a Mac). Very good overall. Explains why the correct answer is correct and why each wrong answer is wrong. I think it expires after 6 months once you start using it, so keep it in mind. I also tried a couple of practical labs (not the tests), but did not find them particularly useful. If you have no practical experience with the concepts (like hashing, etc), they may offer some value, though.

I'm using Android, but assume Apple store has the same apps:

(ISC)² Official CISSP Tests. Good app with some limitations. A few questions had wrong answers. There is no way to mark a question when you are taking a practice test. Once you are done with the practice test and exit the app, your results are gone.
CISSP Practice Tests. Use the free version. Found a few errors, but overall good.

I used a number of other free apps but as I'm checking now, they are either discontinued, or were not very good.

UTILITIES

Chegg Prep. Used it for building flashcards for the topics I needed to review. Terrible app, but it's the one I started to use and it was too late to switch. It can get you by.

VIDEOS

For every topic that I struggled with, I just searched the Internet for the best resource (in most cases, video) to cover it. There are too many to list, but I want to mention this one because it helped me a lot to learn about networking (one of my weak areas):

Sunny Classroom. I just love this guy. :-)

COMMUNITIES

Spent a lot of time here:

r/cissp. Reddit CISSP community where people share a lot of useful resources.
CISSP Exam Preparation - Study Notes and Theory. Started by Luke Ahmed. I learned a lot from following this group and participating in the discussions. Very good questions.
CISSP, CISM and PMP study group by ThorTeaches.com. Thor's group. The posted practice questions are not as tricky as Luke's questions, but still, a good resource to follow.
Adam Gordon's CISSP Q of the D. Adam posts questions on various CISSP domains daily.

How I passed the CISSP exam

2021-10-21T11:58:00.014-07:00

Summary: How I studied and passed the CISSP exam.

On April 17, 2021, I passed the CISSP exam. The exam seemed easier than I had expected it to be, but the road to it was long and hard. I studied intensively for almost a year and practically had no life for four months before the exam. After passing the exam, I shared some insights on the CISSP Exam Preparation - Study Notes and Theory group's Facebook page. This is a slightly redacted copy of that post in case something happens to Facebook. If you are planning to take the exam, check it out along with my other post summirizing the list of resources that I found helpful.

INTRO

I took the exam today [April 17, 2021] for the first time and was done after 100 questions. Having not taken any exams since my college days (20 years ago) and understanding that there are still many areas where I was not fluent, I was about 50% certain I would not pass (actually, considered rescheduling a few times), so it was short of a miracle. Many thanks to Luke [Ahmed] and this [Facebook] group for helping me get ready. It was invaluable. Best of luck to everyone who is going to try it again. Here are some thoughts that may help others.

THE EXAM

Frankly, it was not as hard as I had expected it to be after hearing horror stories. Maybe I got lucky and should just praise God. Or maybe after all the training I had done I was finally in the right mindset. Or maybe both. Anyway, as people say, the questions were indeed not like the questions in the prep tests, but not necessarily in a worse way. I have seen a lot more difficult questions when using Boson and prep apps. I think I had five or so questions that I did not get at all and just picked the answers by gut feeling. I was not sure about a dozen or so questions were, but mostly I felt pretty good. Since they don't give you the answers, it's hard to say what I did right and what I did wrong, but for a few, the answers seemed more revealing than the questions. I was surprised that all abbreviations were spelled out (I thought only ambiguous abbreviations would be spelled out, so could've saved time not learning them and not freaking out about not being able to remember them all). Didn't have any questions that would require calculations or using the pen and paper. Yes, there were questions about some basic laws, regulations, and frameworks but they were all in the context of a described scenario. Did not have to do crypto much, but a few questions required understanding of the basic concepts and algorithm names (but nothing like "how many rounds and block sizes RC6 supports"). Overall, with a couple of exceptions, questions made sense.

THE DAY OF THE EXAM

Took a day off work. I scheduled the exam at 3:30 PM, but should've scheduled it earlier to get it over sooner. Watched Kelly Handerhan's "Why you WILL pass the CISSP" video to set me in the right mood.

THE WEEK OF THE EXAM

Took Monday and Tuesday off to re-watch Thor Pedersen's UDEMY videos (for the third time) at 2x speed (we have the Udemy subscription at work). Reviewed my notes on Wednesday after work. Watched a couple of videos on Thursday and glanced over a few notes covering areas that I still did not get. Came to peace understanding that there were still some topics that I did not know very well.

FOUR MONTHS BEFORE THE EXAM

Practically, had no personal life. Spent most evenings and weekends studying. Read Luke Ahmed's "How to Think Like a Manager" book. Read the "11th Hour CISSP" book. Started following CISSP Exam Preparation - Study Notes and Theory group's Facebook page and a couple of other groups. Bought "Official Study Guide, 8th Edition" and "Official Practice Tests, 2nd Edition". Read a couple of chapters of the official study guide and realize that I couldn't hold all this info in my head, so only used it as reference. Have not used the practice tests book at all because I bought the Official Practice Tests app for Android and it was pretty much the same (UPDATE: Looks like there is a new and better free version available now: CISSP - (ISC)² Official App). Used a number of free test prep apps (pretty much everything I was able to find at the Google play store, some of them were quite useful). Practiced Boson tests (highly recommend). Also tried to do a couple of Boson labs and realized they were mostly a waste of time. I think I practiced something between 1,500 and 3,000 questions. I stopped using each practice app once I realized that the questions started to recycle. A side note about apps: none of them are perfect (some have wrong answers, some have other issues), but I would still recommend everything I used: Boson, official study test prep app, and other apps. By the end, I was getting about 75%-85% on tests on average, depending on the platform. When doing tests, I used Chegg Prep to keep notes of everything I struggled with. I mostly did tests in prep mode and tried to analyze the wrong answers. Did timed exercises, as well, just to get an idea.

ONE YEAR BEFORE THE EXAM

Gave up resisting my manager who insisted on me getting the CISSP certification. Watched Thor Pedersen's Udemy course (a couple of times). Started listening to the old Kelly Handerhan's audio version of the CISSP prep course (pretty much listened to it at 1.5x speed all the time I was in a car driving alone; I think I listened to them 2-3 times). Bought the Boson prep app and then realized that it was only a practice app (no training materials other than labs) and it would expire 6 months after starting to use it, so I held off until I was more or less ready.

BACKGROUND

A software guy. 20+ years of IT (mostly, InfoSec) development experience. Didn't know much about infrastructure, networks, firewalls, etc (before I started studying for the CISSP exam).

How to read a secret from command line

2021-09-08T17:00:00.003-07:00

Summary: A sample of C# code illustrating how to read a masked secret value entered via a console.

The following function can be used to read a secret value, such as a password from a command line:

/// 
/// Reads a secret from command line masking the characters entered by the user.
/// 
/// 
/// Prompt to be displayed for the user (e.g. "Enter password: "). If not specified, the prompt will not be displayed.
/// 
/// 
/// The masking character.
/// 
/// 
/// The string entered by the user.
/// 
private static string GetSecret
(
    string prompt = null,
    char mask = '*'
)
{
    // Input codes requiring special handling.
    const int ENTER         = 13;
    const int BACKSPACE     = 8;
    const int CTRLBACKSPACE = 127;
    const int ESC           = 27;

    // Character codes that must be ignored.
    int[] FILTERED = { 0, 9, 10 /*, 32 space, if you care */ };

    var secret = new System.Collections.Generic.Stack();
    char chr = (char)0;

    // If the prompt was specified, show it to the user.
    if (!String.IsNullOrEmpty(prompt))
      Console.Write(prompt);
    
    // Continue reading entered keys until user presses ENTER or ESC.
    while (((chr = System.Console.ReadKey(true).KeyChar) != ENTER) && (chr != ESC))
    {
        if (chr == BACKSPACE)
        {
            if (secret.Count > 0)
            {
                System.Console.Write("\b \b");
                secret.Pop();
            }
        }
        else if (chr == CTRLBACKSPACE)
        {
            while (secret.Count > 0)
            {
                System.Console.Write("\b \b");
                secret.Pop();
            }
        }
        else if (chr == ESC)
        {
            while (secret.Count > 0)
            {
                System.Console.Write("\b \b");
                secret.Pop();
            }
        }
        else if (FILTERED.Count(x => chr == x) > 0)
        {
        }
        else
        {
            secret.Push((char)chr);
            System.Console.Write(mask);
        }
    }

    System.Console.WriteLine();

    return new string(secret.Reverse().ToArray());
}

How to trim audio (MP3) files

2020-10-02T18:13:00.002-07:00

Summary: PowerShell script to trim beginning and end of the audio (MP3, etc) files.

The following PowerShell script will remove the specified number of seconds from the beginning and/or end of every audio file with the given extension (.mp3 in this case) under the specified folder and all subfolders unerneath (requires FFmpeg binaries):

# Input folder holding audio files.
$inputDir = "Z:\Lectures"

# Seconds to trim from beginning of file.
$trimStart = 0.0

# Seconds to trim from the end of file.
$trimEnd = 9.0

# Path to the directory holding FFMPEG tools.
$ffmpegDir = "c:\ffmpeg\bin"

# Extension of the audio files.
$ext = ".mp3"

# Extension for temporary files.
$tmpExt = ".TMP$ext"

# Paths to FFMPEG tools.
$ffmpeg  = Join-Path $ffmpegDir "ffmpeg.exe"
$ffprobe = Join-Path $ffmpegDir "ffprobe.exe"

# Process all audio files in the directory and subdirectories.
Get-ChildItem -LiteralPath $inputDir -Filter "*$ext" -Recurse -File | ForEach-Object {
    # Original file path.
    $oldFile = $_.FullName

    # Original file name.
    $oldName = $_.Name

    # Temp file path will be in the same folder named after the original file.
    $tmpFile = "$oldFile$tmpExt"

    # Get the length of the audio track (it's a sting holding a floating number with possible new line).
    $duration = (& $ffprobe -v 0 -show_entries format=duration -of compact=p=0:nk=1 $oldFile) | Out-String

    $duration = $duration.Trim()

    # Set new length of the audio by removing the trimmed parts.
    $duration -= ($trimEnd + $trimStart)

    # Trim the file.
    & $ffmpeg -ss $trimStart -t $duration -i $oldFile -acodec copy $tmpFile

    # Delete the original file.
    Remove-Item -LiteralPath $oldFile -Force

    # Rename the temp file to the original.
    Rename-Item -LiteralPath $tmpFile $oldName -Force
}

Minimize your app config file

2019-07-18T10:27:00.000-07:00

Summary: How to keep application configuration files (app.config, web.config) nice and clean.

We use configuration files to store application settings that can be modified, so we do not need to recompile the application. Some applications have lots of settings, but many of these settings are not likely to change or may only change when the application is rebuilt. In such case, here is a nice technique that will allow you to reduce the size of the config file.

Here is the basic idea:

Create a static configuration class (let's call it Config).
In the Config class, implement static methods to get a configuration property value that either gets it from the application's config file (if the setting is defined in the appSettings section) or uses the passed default (you'd need to implement these methods for different data types).
In the Config class, define the static properties that get initialized by calling the methods mentioned above with the hard-coded defaults. To make it easier to remember, the config file's appSettings keys must be named after the Config class properties.

Now, you can remove the settings that are not very likely to change from the config file and if they need to be changed before the application is updated, simply add them back.

Here is the code:

The configuration class is responsible for initialization of the application settings:

using System;
using System.Configuration;

namespace MyApp.Configuration
{
    public static class Config
    {
        public static string OPERATION_LIST = 
            GetValue("OPERATION_LIST", "Create|Read|Update|Delete|Assign|Revoke|Enable|Disable");

        public static string OBJECT_LIST = 
            GetValue("OBJECT_LIST", "User|Group|Role");

        private static string GetValue
        (
            string keyName,
            string defaultValue = null
        )
        {
            string configValue = ConfigurationManager.AppSettings.Get(keyName);

            if (String.IsNullOrEmpty(configValue))
                return defaultValue;

            return configValue;
        }

        private static int GetValue
        (
            string keyName,
            int defaultValue
        )
        {
            string configValue = ConfigurationManager.AppSettings.Get(keyName);

            if (String.IsNullOrEmpty(configValue))
                return defaultValue;

            return Int32.Parse(configValue);
        }

        private static bool GetValue
        (
            string keyName,
            bool defaultValue
        )
        {
            string configValue = ConfigurationManager.AppSettings.Get(keyName);

            if (String.IsNullOrEmpty(configValue))
                return defaultValue;

            return bool.Parse(configValue);
        }

        private static object GetValue
        (
            string keyName,
            Enum defaultValue,
            Type type
        )
        {
            string configValue = ConfigurationManager.AppSettings.Get(keyName);

            if (String.IsNullOrEmpty(configValue))
                return defaultValue;

            return Enum.Parse(type, configValue);
        }
    }
}

Using an application setting is now as easy as referencing the corresponding configuration class property:

string[] operations = Config.OPERATION_LIST.Split('|')
    .Select(op => op.Trim())
    .ToArray();
string[] objects= Config.OBJECT_LIST.Split('|')
    .Select(op => op.Trim())
    .ToArray();

Notice that we do not need to define these values in the application config file unless we have to modify them before we release an application update, in which case, simply add them to the appSettings section:

I assume this must be obvious but just in case: NEVER HARD CODE SENSITIVE INFORMATION (PASSWORDS, ENCRYPTION KEYS, ETC) IN THE APPLICATION SOURCE CODE.

Okay, I'm done for today.

UPDATE: And here is an even better option: BasicConfiguration.

How to get or set a nested class property using C#

2019-07-10T10:36:00.000-07:00

Summary: C# methods to set and get nested class property values.

If you need to get a set a value of a nested object property, here is a couple of functions that can help you do it using reflection (.NET 4.7, C#):

/// 
/// Gets the value of a nested object property.
/// 
/// 
/// Project that owns the property.
/// < /param>
/// 
/// Name of the property.
/// < /param>
/// 
/// Property value (or null, if property does not exists).
/// 
/// 
/// 
/// The code assumes that the property exists;
/// if it does not, the code will return null.
/// 
/// 
/// The property does not need to be nested.
/// 
/// 
/// The code handles both class properties and fields.
/// 
/// 
public static object GetPropertyValue
(
    object source, 
    string name
)
{
    if (name.Contains("."))
    {
        var names = name.Split(new char[] { '.' }, 2);

        return GetPropertyValue(GetPropertyValue(source, names[0]), names[1]);
    }
    else
    {
        PropertyInfo prop = null;

        prop = source.GetType().GetProperty(name);

        if (prop != null)
            return prop != null ? prop.GetValue(source) : null;

        FieldInfo field = source.GetType().GetField(name);

        if (field == null) return null;

        return field.GetValue(source);
    }
}

/// 
/// Sets the value of a nested object property.
/// 
/// 
/// Object that owns the property to be set. 
/// < /param>
/// 
/// Name of the property.
/// < /param>
/// 
/// Property value.
/// < /param>
/// 
/// 
/// The code assumes that the property exists;
/// if it does not, the code will do nothing.
/// 
/// 
/// The property does not need to be nested.
/// 
/// 
/// The code handles both class properties and fields.
/// 
/// 
public static void SetPropertyValue
(
    object target,
    string name, 
    object value
)
{
    var names = name.Split('.');

    for (int i = 0; i < names.Length - 1; i++)
    {
        PropertyInfo prop = target.GetType().GetProperty(names[i]);
        if (prop != null)
        {
            target = prop.GetValue(target);
            continue;
        }

        FieldInfo field = target.GetType().GetField(names[i]);
        if (field != null)
        {
            target = field.GetValue(target);
            continue;
        }

        return;
    }

    PropertyInfo targetProp = target.GetType().GetProperty(names.Last());

    if (targetProp != null)
        targetProp.SetValue(target, value);
}

How to rotate a video without re-encoding

2017-11-17T16:12:00.002-08:00

Summary: A few tips on video rotation.

If your phone messes up the rotation metadata flag in a video file, download ffmpeg and run the following command:

ffmpeg -i input.mp4 -c copy -metadata:s:v:0 rotate=0 output.mp4

This should fix the problem without re-encoding the video. If it does not, try setting the rotate switch to a different number, such as 90, 180, or 270. For additional information about video orientation MP4 and other video files, check the See also section.

See also:
iPhone recorded videos getting rotated on Windows systems
Rotate a MP4 file, while preserving codec and quality attributes
Rotate mp4 videos without re-encoding
Rotating videos with FFmpeg
How to rotate a video 180° with FFmpeg?

How to fix slow startup for old Photoshop/Premiere Elements apps (on Windows)

2017-11-17T15:50:00.001-08:00

Summary: Easy way to fix slow startup issues for older versions of Adobe products (on Windows).

If you have an older version of Adobe video and photo editing products, such as Photoshop Elements or Premiere Elements, you may be irritated with the long startup time, which could take several minutes. Apparently, the applications try to connect to a server that is no longer in service (btw, excellent job, Adobe!), so they wait... and wait... and wait... The good thing is that there seems to be an easy fix for this.

According to the answer to this post, you just need to add the following entry to your hosts file located in the %WINDIR%\System32\Drivers\Etc folder:

127.0.0.1   static.photoshop.com

This solved the problem form my Photoshop Elements 9 and Premiere Elements 13 instances running on Windows 7 (yeah, I know, need to upgrade to Windows 10, but that's a different story).

Enjoy!

Save STDOUT/STDERR to clipboard (and more)

2017-10-20T14:51:00.002-07:00

Summary: How to redirect the STDOUT or STDERR stream to clipboard.

Note to self (mostly), in case I forget the command that would redirect standard output or standard error stream and save it on the clipboard.

Redirect STDOUT to clipboard:

command | clip

Redirect STDERR to clipboard:

command 2>&1 | clip

The following will save the contents of the current directory to the clipboard:

dir | clip

Now, let's try the following:

dir xyz: | clip

The clipboard now will hold something like this:

 Volume in drive C is SYSTEM
 Volume Serial Number is 1234-ABCD

 Directory of C:\Windows\SysWOW64

Now, let's redirect STDERR to clipboard:

dir xyz:2>&1 | clip

The clipboard now will hold something like this:

"xyz:" is not a recognized device.
"xyz:" is not a recognized device.
 Volume in drive C is SYSTEM
 Volume Serial Number is 1234-ABCD

 Directory of C:\Windows\SysWOW64

File Not Found

How to clean up BIN and OBJ folders in a Visual Studio solution

2017-08-22T11:24:00.002-07:00

Summary: Some ideas on cleaning up intermediate and output folders in Visual Studio projects.

There may be better (and more elegant) ways of cleaning up the output (BIN) and intermediate (OBJ) folders generated by Visual Studio build process, but the following script is probably the easiest option you can use:

@echo off
rem Delete BIN and OBJ folders from the immediate folder and all subfolders.
rem

rem Switch to the script folder.
cd "%~dp0"

rem Use the following to suppress the 'File Not Found' message if no folders are found.
setlocal enabledelayedexpansion 
for /f "tokens=*" %%G in ('dir /B /AD /S bin 2^>nul') do rmdir /S /Q "%%G"
for /f "tokens=*" %%G in ('dir /B /AD /S obj 2^>nul') do rmdir /S /Q "%%G"

Notice that the script call setlocal enabledelayedexpansion to allow the 2^>nul redirection in the for loops (without it, it would output the "File Not Found" message if the folder and subfolders do not hold the "BIN" or "OBJ" folders. Also, make sure, you place the file in the root of the solution folder.

See also:
How to clean Visual Studio bin and obj folders
I want to delete all bin and obj folders to force all projects to rebuild everything

How to run a .bat from inside the IDE
Want to suppress File not found output
Suppress command line output

Rapid prototyping with jsFiddle for web developers

2016-04-27T16:44:00.001-07:00

Summary: How to use jsFiddle for building wireframes and rapid prototyping.

Recently, I needed to build interactive prototypes of a web form. I do not own a license of a professional prototyping tool (like Balsamiq, HotGloo, UXPin), so I tired several free online options (namely, iPLOTZ, concept.ly, MockFlow) and appreciated the ease of drag-and-drop; however, making these prototypes respond to interactive events (mouse clicks, selection changes, etc) turned into a hassle.

I also tried a couple of desktop options, but had even less luck with Pencil (couldn't figure out how to make a combo box display multiple entries), Visio 2013 ("Where is the combo box, Lebowski?"), and Blend for Visual Studio 2013 ("You're entering the world of pain!").

I was entertaining an idea of using animations in PowerPoint, when it struck me:

Why not use jsFiddle?

If, after reading the previous sentence, the first question that popped into your mind was "What the heck is jsFiddle?", you may not realize that saying "What the heck!" is really worse than saying "What the hell!". But nonetheless, for those just coming out of a coma:

jsFiddle is a free web-based tool that allows you to quickly test HTML/JavaScript/CSS. But wait, there's more!

Here is what a jsFiddle screen looks like:

You enter HTML, CSS, and JavaScript code into the corresponding panels, click the Run button, and see the result of your work in the window appropriately named Result. It's that simple.

Let's summarize what jsFiddle has to offer:

It's free (as in "it ain't cost sh*t").
It's web-based (no crap to install).
It's not using Adobe Flash, like most other online prototypes do (they still do, don't they?).
It uses HTML, CSS and JavaScript (you already know these, right?).
It uses a standard web programming model (no need to learn proprietary controls).
It supports pretty much every popular JavaScript/CSS framework (yay to jQuery! yay to Bootstrap!).
It can incorporate any custom JavaScript/CSS framework (assuming it has a public URL).
It keeps versions of your changes (version control by default).
You can send a URL of your prototype for a review or do a live demo (with some quirks, though).
You can collaborate with others on a prototype (although, I haven't tried).

The bottom line is that using jsFiddle, you can quickly build a prototype and implement the functionality that is only constrained by the limitations of the same technologies your applications uses (JavaScript, CSS, HTML). In the other words, there are no practical constraints. It's almost too good to be true. Why haven't I thought about it before?

Anyway, if you want to build a wireframe or a quick prototype using jsFiddle, do the following:

Create an account (if you don't have one).
Log in and open the editor.
While in the editor, under the Fiddle Meta section on the left side, enter the title and description of your prototype (wireframe). If you do not want to make it public (discoverable via search), leave the title field blank.
Add your HTML, CSS, JavaScript.
Click the Run menu option to preview the functionality.
When you are happy with the result, click the Save (or Update) menu button to keep the changes.
The public link to the fiddle can be found in the Embed Code section of the Embed screen (to open the Embed screen, click the Embed menu option).

If you close jsFiddle and come back, you will find your fiddles in the dashboard (to access the dashboard link from the editor, click your account name in the top right corner of the page). The dashboard shows your public and private fiddles (proper descriptions will make it easier for you to locate private fiddles):

Now, a bit of jsFiddlespeak, if you do not mind.

Visibility: You may have noticed somewhat non-traditional use of the term public. As I mentioned above, public means that a fiddle can be found via a search, and non-public means that to access a fiddle, someone must know the fiddle's URL (non-public fiddles are still open to public).

Baseline: Every time you save a fiddle (via the Save or Update menu option), jsFiddle will create and retain a new version. You can access a specific version of the fiddle by appending the version number to the fiddle's URL. For example, assume that your jsFiddle profile name is jdoe and you make 13 changes to a fiddle with ID qdn9f737, the URLs of the version history will look like these:

https://jsfiddle.net/jdoe/qdn9f737/1/
https://jsfiddle.net/jdoe/qdn9f737/2/
https://jsfiddle.net/jdoe/qdn9f737/3/
...
https://jsfiddle.net/jdoe/qdn9f737/12/
https://jsfiddle.net/jdoe/qdn9f737/13/

The non-versioned URL will correspond to whichever version you set as base (the first version by default) and will look like this:

https://jsfiddle.net/jdoe/qdn9f737/

You can define any version as base by opening this version in the editor and clicking the Set as base menu option (in certain cases, you may need to save the version first).

Finally, a few tips to help you get most out of jsFiddle (these are mostly notes to self, but others may find them handy).

Use the gear buttons (in the right top corners of the corresponding panels) to configure the HTML, CSS, and JavaScript settings. In particular, you can specify the version of HTML (such as HTML 5 or HTML 4.0.1 Strict) to use and а JavaScript framework (such as jQuery 2.2.3 or AngularJS 1.4.8) to include. You can only pick one option from the JavaScript Frameworks and Extensions list, but you can include additional dependencies as external resources.

To include an external resource (other than the framework or extension selected in the JavaScript Frameworks and Extensions list), click the External Resources header in the left pane of the page, paste or type in the URL of the framework file (normally, the resource's CDN address) in the JavaScript/CSS URI field, and click the plus sign. Here are the URLs of the common CDNs:

If you want to share your prototype, but do not want others to see the JavaScript/HTML/CSS code, uncheck the HTML, CSS, and JavaScript option under the Tabs heading in the Embed options (notice that the source URL in the Embedded Code section ends with embed/result/):

To make the prototype look better when viewed in the the full screen mode, you may want to limit the maximum width of the page. Enter the code similar to this in the CSS panel:

html {
  max-width: 1200px;
  margin: 0 auto;
  background: #eee; /* Fills the page */
  position: relative; /* Fix for absolute positioning */
}

Have fun!

Generate filename-friendly datetime in Windows shell script

2016-04-21T14:23:00.001-07:00

Summary: Windows batch script to generate timestamp for a filename.

People who write Windows Shell (AKA batch or .BAT) scripts for living sometimes need to create file (or directory) names using timestamp values based on local current date and time. This is not as trivial as it may sound. First, there is no shell command that would return a timestamp in a custom format, and the standard command may return a value containing illegal (for filenames) characters, such as colons.

There are articles that address this issue, but many proposed solutions do not accommodate region specifics, so they may work for an OS configured for one region, but fail for another.

The following script will generate a filename-friendly local timestamp for any region:

@echo off
rem -----------------------------------------------------------------
rem MAIN routine
setlocal & pushd

call :GET_TIMESTAMP
set timestamp=%ret%

echo %timestamp%

rem End of the main routine.
popd & endlocal 
goto :EOF

rem -----------------------------------------------------------------
rem Generate current timestamp in the format:
rem
rem YYYYMMDDhhmmss (as shown here), or
rem YYYYMMDD_hhmmss (commented out), or
rem YYYMMDDhhmmssmmm (commented out), or
rem YYYMMDD_hhmmss_mmm (commented out)
rem
rem Uncomment the block that generates the desired format and comment
rem out the alternate implementations.
rem
rem Returns %ret%.
:GET_TIMESTAMP
setlocal

for /f "usebackq tokens=1,2 delims==" %%i in (`wmic os get LocalDateTime /value 2^>NUL`) do (
if '.%%i.'=='.LocalDateTime.' set ldt=%%j
)
rem Without milliseconds, without underscore: 20160421140125
set timestamp=%ldt:~0,4%%ldt:~4,2%%ldt:~6,2%%ldt:~8,2%%ldt:~10,2%%ldt:~12,2%
rem echo %timestamp%

rem Without milliseconds, with underscore: 20160421_140125
rem timestamp=%ldt:~0,4%%ldt:~4,2%%ldt:~6,2%_%ldt:~8,2%%ldt:~10,2%%ldt:~12,2%
rem echo %timestamp%

rem With milliseconds, without underscores: 20160421140125202
rem set timestamp=%ldt:~0,4%%ldt:~4,2%%ldt:~6,2%%ldt:~8,2%%ldt:~10,2%%ldt:~12,2%%ldt:~15,3%
rem echo %timestamp%

rem With milliseconds, with underscores: 20160421_140125_202
rem set timestamp=%ldt:~0,4%%ldt:~4,2%%ldt:~6,2%_%ldt:~8,2%%ldt:~10,2%%ldt:~12,2%_%ldt:~15,3%
rem echo %timestamp%

endlocal&set ret=%timestamp%
goto :EOF

How to create and share a school calendar using Google

2015-10-03T02:38:00.000-07:00

Summary: A walk-through explaining how to create and share a public school calendar.

I have three kids enrolled in two schools that operate under different calendars. To keep track of their schedules, I set up the school calendars on my phone (and PC), so that I get event notifications and reminders. It works well, but comes at a cost: in the beginning of each school year I spend 1-2 hours manually entering the information about the school events (minimum days, holidays, days off, back to school nights, etc.) into my personal calendar. And so do other parents at my kids' schools, as well as millions of parents nationwide. Sooner or later the schools will learn how to make the process more efficient, but in the meantime, you -- a school administrator, a teacher, or a volunteer -- can help us. It won't be hard.

In this article, I'll explain how to make it easy for parents to see a school calendar on a mobile device (iPhone, Android device, Windows phone or tablet) and keep this calendar up-to-date. You will no longer need to print calendars on paper (yay, trees!) or have parents enter them manually. A public calendar allows you to add new events, update existing events, delete cancelled events, set reminders, provide helpful event details (such as instructions or locations of off-site events) and subscribers will see them instantly. It lets you share the same calendar online (at your school's website). And it does not limit you to a school schedule. You can follow the same approach to set up a calendar for any organization or activity, such as a sports team or a volunteering project.

Before we get down to the nitty-gritty, let me first clarify the requirements and limitations.

REQUIREMENTS: A user must have a Google account.

While you may keep a personal calendar locked to your your mobile phone or computer, inside of iCloud, or in Outlook, for a public calendar you better use Google Calendar. It supports all major platforms (iPhone, Android, Windows), has wide adoption, and offers most features.

If you (a school calendar administrator or creator) do not have a Google account, you can easily create one (it's free). A Google account gives you access to the Calendar features including ability to create public calendars. You may prefer to create a special Google account that would "own" the school calendar, so you can transfer it to someone else in case you no longer want to manage it (Google makes it really easy to switch between multiple accounts).

To get real time updates, Google calendar subscribers (parents) will also need Google accounts. As a subscriber, you do not need to actively use a personal Google calendar (if you prefer something else), but you will need it to sync the school calendar with your mobile device.

WARNING: If you have a fundamental objection to using Google, there may be a similar approach to sharing a school calendar using a different provider (say, Apple, Yahoo!, or Microsoft), but it'd be more complex (if possible at all), so let's assume that at this point both calendar administrators and subscribers have Google accounts.

Calendar creation process
To set up a school calendar, follow these steps:

Create a public calendar
First, you create a public Google calendar for your school online. Here is a short video explaining how to do this (if you prefer a written tutorial, read Create & manage a public Google calendar):

Although you can change it later, try to give the calendar a meaningful name (or title). Keep in mind that a long name may not show completely on mobile devices, so place the most significant parts of the name in the beginning. Here are some examples of calendar names that I used, so you may want to follow a similar format:
- CCHAT, Sacramento (School Calendar) (see preview)
- CMP (School Calendar) (see preview)
If you want to allow other administrators to maintain the calendar (create and make changes to the events), set appropriate sharing permissions (read the Control what others can see help section).
Add events to the calendar
To make sure you add an event to the wright calendar, when you work with your school calendar, temporarily turn off all other calendars. Here are some tips.

When naming events, follow the same naming convention. To make it easier for subscribers identify which calendar an event belongs to, include a short name of the school in the name of event. Here are some examples of event names that I used for a California Montessori Project's school calendar (you can browse the calendar to see more examples and details):
- Minimum Day (CMP)
- School Break (CMP)
- School Holiday (CMP)
- School Closed (CMP)
- Last Day of School/Minimum Day (CMP)
As you may have noticed, I prefer to keep titles short and simple, but I also use the description field for additional information.

Include details that parents may find useful in the event description. You can use description for special instructions or any type of information you would normally provide in a letter or email invitation.

For off-site events, specify the address in the location field. The address will help parents find location on map and use navigation apps.

For some events, such as minimum days, it may make sense to set up reminders. Keep in mind that that parents may need time to travel, so give them enough time (I'd say, for a full-day event, a 12-hour advanced reminder would be fine, while for all other events, an hour would be enough). Use pop-ups for reminders.

For repeating or multi-day events (such as regular after school activities or school breaks), set up occurrence rules (do not duplicate events).

Instead of creating each event from scratch, use the Duplicate Event feature, which allows you to copy an existing event, and then update all relevant information. For example, when defining school holidays, set up an even for the Labor Day (I think it's the first holiday in a typical school year), make sure you use proper naming convention and define event details. Then duplicate it to make an entry for Veteran's Day (don't forget to adjust event information), and continue doing the same for other school holidays.
Advertise the calendar
Once you get the calendar up and running, you send its address (the URL of the calendar's ICS file) to the parents. At the time of writing, you could locate the calendar address by following this steps:
- Open your Google calendar page.
- Click the settings (gear) button in the top right corner, and select the Settings option from the pop-up menu.
- Under the Calendar Settings heading, click the Calendars tab link.
- Click the name of your public school calendar displayed in the My Calendars section.
- Scroll down to the Calendar Address section and click the iCal button (make sure you use the public iCal address and not the private one).
A window will pop up showing the calendar address that looks like this:

https://www.google.com/calendar/ical/abcd0efghi23jk45lmn45o6pqr%40group.calendar.google.com/public/basic.ics

Make sure that the address ends with the .ics extension. This is the address of the calendar that you will need to share with parents.
Maintain the calendar
You can use the same calendar year over year and make changes to it at any time. All changes to the calendar will be automatically delivered to the subscribers. As a bonus, you can also add a Google calendar to your website.

Calendar subscription process
To see calendar events on your mobile device, such as phone or tablet, do the following:

Subscribe to calendar
Parents subscribe to the calendar using the provided address of the iCAL (.ics) file. The steps are outlined in the Add someone else's Google calendar article (see the Add using a link section). Alternatively, you can subscribe to a calendar by clicking the Add to Google Calendar shortcut displayed at the bottom right corner of the calendar's HTML page.
Sync calendar with phone
If you do not see the school calendar events reflected on your phone (or other mobile device's) calendar, you may need to make a couple of adjustments. First, follow the instructions outlined in the Sync Calendar with a phone or tablet article. Depending on the device configuration, it may not be enough, so follow your device maker's recommendations. For example, here are instructions for Windows and iPhone users. For an Android device, you many need to clear calendar data and resync the calendar (if you are not sure how to do this, search for: <your device name> +clear +calendar +data and <your device name> +sync +calendar).

LINKS FOR CMP, ORANGEVALE PARENTS:

CMP, Orangevale School Calendar Page (short link) * | CMP, Orangevale Calendar (iCAL) file
Crater Lake, CMP, Class Calendar Page (short link) ** | Crater Lake, CMP, Class Calendar (iCAL) file
Denali, CMP, Class Calendar Page (short link) ** | Denali, CMP, Class Calendar (iCAL) file

LINKS FOR CCHAT, SACRAMENTO PARENTS:

CHAT, Sacramento School Calendar Page (short link) * | CCHAT, Sacramento School Calendar (iCAL) file

* You can add this school calendar by clicking the iCAL / YEARLY link at the top of the calendar page.
** You can add this school calendar to your Google calendars by clicking the link at the bottom right corner of the calendar page.

Easy? I think so.

I'm almost done, but before we part, one final though. In fact, this is the first question you need to address:

How many calendars do you want to keep?

Do you want to maintain a single district calendar or multiple calendars? Do you need a separate calendars for primary, middle, and high schools? Do you want the calendar to include the information relevant to teachers and staff (such as training)? Depending on the size of your district, differences in school schedules, and other factors, you may choose one approach over another. As a parent, I'd like a single school calendar with information relevant to students only and a class calendar reflecting class-specific events, such as field trips, project deadlines, and due dates. I do not care when and where teachers and staff attend training, but I do care when the school is closed, but others may have other preferences.

I hope this information was helpful. If you have questions or want to leave feedback, please leave a comment.

See also:
Embedding Google Calendar in eChalk
Can I get my Google Calendar shown in my iCloud Calendar on my PC?

Build API documentation with Sandcastle Help File Builder

2015-03-05T15:27:00.000-08:00

Summary: How to build awesome API documentation using Visual Studio, XML code comments, Microsoft Markup Assistance Language (MAML), and Sandcastle Help File Builder (SHFB).

A couple of weeks ago, I gave this presentation to the Sacramento .NET User Group:

View on SlideShare

The presentation explains how to build first-class API documentation using Visual Studio, Sandcastle, and other tools and technologies. The goal of the presentation is to show how to build documentation with less effort and more fun.

The PowerPoint file (with links and notes) and the demo project can be found here:

The demo project page outlines the dependencies and requirements for building the solution and using the assemblies.

If you run into any issues or have questions, please post a comment below or contact me directly.

Technobrief #15

2015-02-13T17:31:00.010-08:00

Summary: Recent (and not so recent) findings of software, articles, and more.

CSS

Learn CSS Layout
This site teaches the CSS fundamentals that are used in any website's layout.
Responsive Menu Concepts
Discusses four main concepts for building responsive menus.

Design

50 Incredible Freebies for Web Designers, February 2015
Free icon sets, templates, color palettes, and more.
6 Steps to Perfecting Minimalism in Web Design
Some ideas on making your website more user-friendly.
Good UI Ideas
A running list of ideas for improving UI usability for both owners and customers.
How to Modify Bootstrap Quickly and Effectively
Introduces several tools and options for Bootstrap UI modification.

Fonts

101 Essential Free Fonts for Web Designers
Fonts that are genuinely free (not just one style or weight free), a balance of fonts that work well for body text as well as display, and a full collection of fonts that are pleasing to the eye.
10 Best New Free Fonts
A small, yet very good, collection.

Graphics

Graphic resources for everyone
Find free vectors, PSD, icons and photos.

JavaScript

Gridforms
A tiny Javascript/CSS framework that helps you make forms on grids with ease.
SlabText
A JQuery plugin for producing big, bold, and responsive headlines.

Programming

The Ultimate Guide for Getting Started with Foundation
Introduction to Foundation: one of the two big-name HTML/CSS/JS frameworks for front-end developers.
Say Hello to PowerShell
A brief tutorial.

Software

DVDStyler
Free slide show and DVD authoring tool. Important features: allows creation of interactive menus (from templates), support for multiple video formats.
GlassWire
Free network monitor & security tool with a built in firewall.
LightWorks Free
The free version of a video editing application (see limitation in the version comparison charts).
MP3 Diags
Identifies and fixes problems in MP3 files, such as duplicate tags, wrong audio duration, character encoding, and many others.
Windows Media Preview
Shows thumbnails for all media files in Windows Explorer.

Tools

A Dozen Tools for Removing Almost Any Malware An article providing all the information needed to remove even the most tenacious malware infestation.
ITTT (If This Then That)
Create alerts and notifications for a wide range of conditions: weather, shopping, etc.
List of Mockup/Prototyping Tools
An extensive collection (although, with no descriptions).

Build responsive websites with Visual Studio 2013 and Bootstrap 3.0

2014-03-27T13:22:00.003-07:00

Summary: Materials for the Sacramento .NET User Group presentation.

Thanks a lot to everyone who attended my presentation yesterday. You have been an awesome audience. Also, many thanks to Josh Gurin (TEKsystems) for the pizzas and wings and Jason Singh (Microsoft) for the excellent meeting space. I was a bit concerned about parking, but there were lots of free after 6 PM parking spaces around the building.

Here are the materials I promised:

In case you don't want to bother downloading the files, here is the presentation:

View on SlideShare

The PowerPoint slides provide the same information as the web application built by the demo project. If you only want to check references and resources mentioned at the session, just use the slides. If you intend to see how the concepts were applied in the actual application, get the project. When you run the demo app, you will see the same content available in the presentation, although in a slightly different format. Links should work from both the presentation and the demo app.

If you run into any issues or have questions, please post a comment below or contact me directly.

See also:
The ultimate guide to Bootstrap by By Cameron Chapman
25 Free & Premium Bootstrap Admin Templates

WiX woes: What is your installer doing?

2013-05-10T13:59:00.001-07:00

Summary: How to detect different modes of installation.

When building an application installer, it's often necessary to distinguish between different modes of installation, i.e. initial installation, repair, upgrade, uninstall, etc. And as with everything important in MSI, detecting the mode of installation is a PITA (and by PITA, I do not mean flat bread of Mediterranean origin). To help you a little bit, here is a table adopted from a StackOverflow topic (and comments), that shows the values of various Windows Installer properties can help you determine the installation mode:

	Install	Uninstall	Repair	Modify	Upgrade
INSTALLED	FALSE	TRUE	FALSE	TRUE	TRUE
REINSTALL	TRUE	FALSE	TRUE	FALSE	FALSE
REMOVE="ALL"	FALSE	TRUE	FALSE	TRUE	TRUE
UPGRADINGPRODUCTCODE	TRUE	FALSE	TRUE	TRUE	TRUE

You can use logical operators NOT, AND, OR to build complex conditions.

Here is how you can detect some common conditions:

First-time installation

NOT Installed

Any installation

NOT Installed AND NOT PATCH

Installation and repairs

NOT REMOVE

First-time installation and repairs

NOT Installed OR MaintenanceMode="Modify"

Upgrades only (during uninstall phase)

Installed AND UPGRADINGPRODUCTCODE

Upgrades

Installed AND NOT REMOVE

Full uninstall (except when triggered by a major upgrade)

(REMOVE="ALL") AND (NOT UPGRADINGPRODUCTCODE)

Any uninstall

REMOVE~="ALL"

If you notice errors or want to include some other conditions, please post a comment.

See also:
MSI Property Patterns: Upgrading, FirstInstall and Maintenance
Upgrading, FreshInstall, Maintenance and other MSI convenience properties
MSI Writing Guidelines: Installation Scenarios
How to execute custom action only in install (not uninstall)

My Walmart account was hacked

2013-04-25T12:42:00.000-07:00

Summary: Lessons from my Walmart account hacking incident.

Out of the blue, I get an email from Walmart:

Dear Alek Davis,

Personal information associated with your Walmart.com account - name, email address and/or password - has been successfully updated as requested. If the account change included an update to the email, for your added security this account update confirmation is sent to both the new and old email addresses. All future emails will be sent to the new address only.

If the account information update is correct, no further action is needed.

If you did not make these changes to your account, please call us immediately at 1-800-966-6546.

If you have any questions, please reply to this email and let us know how we can help.

We appreciate the opportunity to assist you and look forward to your next visit.

Sincerely,

Your Walmart.com Customer Service Team

I try to log on to my Walmart account and fail to authenticate. I attempt to use the I Forgot My Password feature, but get a message stating that my email address is not registered with Walmart. It's obvious: someone hacked my Walmart account!

I call the above mentioned 1-800 number, but the customer support department is closed (it's around 10 PM PST, but apparently, the world's largest retailer cannot afford 24x7 customer support). There is no option to report the problem online. What's a girl to do?

The best thing I can do is send an email reply describing the problem. I get a canned response indicating that I will get a human response within 24 hours. Okay, what's next?

Results from a quick Google search suggest that a common pattern of Walmart hacking involves using saved credit card data to purchase digital goods. So, I log on to my credit card's account (for the card that I normally use at Walmart.com) and see two unauthorized transactions: one in the amount of $60 (turns out to be 2 Straight Talk 1000-Minute, 1000-Text, 30MB Web Access Service Cards), and another in the amount of $50 (2 SKYPE $25 Prepaid eGift Cards). I call the credit card company to report fraud. I also checked other credit cards that could've been on file with Walmart, but do not notice anything suspicious.

I try logging on to Walmart.com again, and notice a strange address popping up in the email field of the Sign In form for a second just before it is overwritten by my original (and no longer good) address filled in by LastPass. Apparently, I have a low-security personalization cookie, that is not good for anything important (like checking or changing account info, or submitting orders), but it could give me some info about the hacker. I disable LastPass and reload the form. Get the email field populated with this address: ssuper981@yahoo.com. Hello, hacker. How're you doing?

Silly idea: what if I try to log in with my original password? The hacker can't be that careless, but... One... two... three... I'm in! Dear, ssuper981@yahoo.com, thank you for failing Hacking 101. I change my email address back, change the password, and remove all credit card info from the account. I see the two orders in the processing state, and successfully cancel one of them. I use a form to send an order cancellation request for the second purchase, but apparently the Skype eGift cards have been already sent. Well, it's now between Walmart and my credit card company to dispute the charge.

What else can I do? I go to the Yahoo! Security Center and try to find an option to report fraudulent activity coming from a Yahoo! email, but Yahoo! does not provide any way to do this (via a form, email, or phone).

The next morning, I call Walmart (thank God Walmart can afford customer support during normal business hours) to report the incident to a human and have a short conversation with a nice woman (btw, have the companies started bringing customer support back from the foreign lands? talking to a motivated native speaker is so refreshing!). Now, it's time to get back to life, but first, lessons learned:

Never save credit card information when shopping online! Yeah, it's convenient, but may eventually cause more hassles.
Read #1.

And a couple of comments:

Walmart: No 24x7 customer support? Seriously? Even for security issues? Come on, you can do better!
Walmart: Good call on sending notification to old customer's email on personal profile changes. Have I not seen this message, it would have taken me much longer to realize that my account was hacked.
Walmart: Shouldn't user activity that starts with personal profile (and email) changes and is followed by an immediate purchase of digital goods raise a flag for suspicious activity? I know that you rush to get a payment, but you see: you lost $60 (which could've easily been $110), and I'm sure you need that money to hire more support people (at the very least, for security related issues).
Yahoo!: Would it be too much to ask for some way of reporting fraudulent activity originating from a Yahoo! email account? Just asking.

Have a nice day, everyone. Be safe!