Bharath Tech Update

Docker Quick Reference

2018-05-15T06:28:00.001-05:00

In My Words
"Docker automates the repetitive tasks of setting up and configuring multiple (dev/qa/prod) environments so that developers can focus on what matters: building great software"

Listing containers


# List running containers 
docker ps

# List all containers
docker ps -a

Starting/Stopping containers

# Start 
docker start containerName

# Stop
docker stop containerName

Removing containers

# Remove container 
docker rm containerName

# Stop and remove container
docker rm -f containerName

# Remove all exited containers
docker rm -v $(docker ps -a -q -f status=exited)

Running commands in new containers

docker run imageName command arguments

# Example
docker run docker/whalesay cowsay Hello

# Assign a name to the container
docker run --name myName docker/whalesay cowsay Hello

# Run with a specific tag of an image
docker run node:6.9.1 node --version

# Run container in background
docker run -d -p 80:80 --name webserver nginx

See Docker run reference for more …

Images

Listing local images

docker images

Removing images

docker rmi imageName

# Remove unwanted dangling images
docker rmi $(docker images -f "dangling=true" -q)

Searching for images

# Search the Docker Hub for images
docker search searchWord

Pulling images

docker pull imageName

# Pull a specific tag
docker pull imageName:tag

# Example: Get a specific node version
docker pull node:6.9.1

Building image from Dockerfile

docker build .

# Name the image
docker build -t imageName .


# Tag the image
docker build -t imageName:1.0.0 .

Docker Swarm Cluster Creation

PS C:\windows\system32> docker swarm init --advertise-addr 10.79.124.174
Swarm initialized: current node (x6ekx7h660cg8nkneujs0n0jf) is now a manager.

To add a worker to this swarm, run the following command:

docker swarm join --token SWMTKN-1-04osgsy3kig1sdzl0q13w7sw5964515jt6c9dkqvjzsk6tntne-1ascqzq63u3gd6xrmp3qzk8ew 10.7
9.124.174:2377

To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions.

Billing Options

2017-09-20T02:53:00.000-05:00

Billing Options

Physical Goods
Assets Owned
Usage Based Services
Professional Services
Recurring Servicies

The REST architectural style - six constraints

2017-09-20T02:52:00.003-05:00

The REST architectural style describes six constraints. These constraints, applied to the architecture, were originally communicated by Roy Fielding in his doctoral dissertation (see http://www.ics.uci.edu/~fielding/pubs/dissertation/rest_arch_style.htm) and defines the basis of RESTful-style.

The six constraints are:

Uniform Interface

The uniform interface constraint defines the interface between clients and servers. It simplifies and decouples the architecture, which enables each part to evolve independently. The four guiding principles of the uniform interface are:

Resource-Based

Individual resources are identified in requests using URIs as resource identifiers. The resources themselves are conceptually separate from the representations that are returned to the client. For example, the server does not send its database, but rather, some HTML, XML or JSON that represents some database records expressed, for instance, in Finnish and encoded in UTF-8, depending on the details of the request and the server implementation.

Manipulation of Resources Through Representations

When a client holds a representation of a resource, including any metadata attached, it has enough information to modify or delete the resource on the server, provided it has permission to do so.

Self-descriptive Messages

Each message includes enough information to describe how to process the message. For example, which parser to invoke may be specified by an Internet media type (previously known as a MIME type). Responses also explicitly indicate their cache-ability.

Hypermedia as the Engine of Application State (HATEOAS)

Clients deliver state via body contents, query-string parameters, request headers and the requested URI (the resource name). Services deliver state to clients via body content, response codes, and response headers. This is technically referred-to as hypermedia (or hyperlinks within hypertext).

Aside from the description above, HATEOS also means that, where necessary, links are contained in the returned body (or headers) to supply the URI for retrieval of the object itself or related objects. We'll talk about this in more detail later.

The uniform interface that any REST services must provide is fundamental to its design.
Stateless

As REST is an acronym for REpresentational State Transfer, statelessness is key. Essentially, what this means is that the necessary state to handle the request is contained within the request itself, whether as part of the URI, query-string parameters, body, or headers. The URI uniquely identifies the resource and the body contains the state (or state change) of that resource. Then after the server does it's processing, the appropriate state, or the piece(s) of state that matter, are communicated back to the client via headers, status and response body.

Most of us who have been in the industry for a while are accustomed to programming within a container which provides us with the concept of “session” which maintains state across multiple HTTP requests. In REST, the client must include all information for the server to fulfill the request, resending state as necessary if that state must span multiple requests. Statelessness enables greater scalability since the server does not have to maintain, update or communicate that session state. Additionally, load balancers don't have to worry about session affinity for stateless systems.

So what's the difference between state and a resource? State, or application state, is that which the server cares about to fulfill a request—data necessary for the current session or request. A resource, or resource state, is the data that defines the resource representation—the data stored in the database, for instance. Consider application state to be data that could vary by client, and per request. Resource state, on the other hand, is constant across every client who requests it.

Ever had back-button issues with a web application where it went AWOL at a certain point because it expected you to do things in a certain order? That's because it violated the statelessness principle. There are cases that don't honor the statelessness principle, such as three-legged OAuth, API call rate limiting, etc. However, make every effort to ensure that application state doesn't span multiple requests of your service(s).
Cacheable

As on the World Wide Web, clients can cache responses. Responses must therefore, implicitly or explicitly, define themselves as cacheable, or not, to prevent clients reusing stale or inappropriate data in response to further requests. Well-managed caching partially or completely eliminates some client–server interactions, further improving scalability and performance.
Client-Server

The uniform interface separates clients from servers. This separation of concerns means that, for example, clients are not concerned with data storage, which remains internal to each server, so that the portability of client code is improved. Servers are not concerned with the user interface or user state, so that servers can be simpler and more scalable. Servers and clients may also be replaced and developed independently, as long as the interface is not altered.
Layered System

A client cannot ordinarily tell whether it is connected directly to the end server, or to an intermediary along the way. Intermediary servers may improve system scalability by enabling load-balancing and by providing shared caches. Layers may also enforce security policies.
Code on Demand (optional)

Servers are able to temporarily extend or customize the functionality of a client by transferring logic to it that it can execute. Examples of this may include compiled components such as Java applets and client-side scripts such as JavaScript.

Complying with these constraints, and thus conforming to the REST architectural style, will enable any kind of distributed hypermedia system to have desirable emergent properties, such as performance, scalability, simplicity, modifiability, visibility, portability and reliability.

NOTE: The only optional constraint of REST architecture is code on demand. If a service violates any other constraint, it cannot strictly be referred to as RESTful.

AnyPoint Platform Exchange 2.0 - Whats New?

2017-07-31T23:47:00.001-05:00

AnyPoint Platform Exchange 2.0 - Whats New?

VM connector in the flow

2017-07-27T07:26:00.000-05:00

VM connector creates a transport barrier in the flow:

In a transport barrier, your Mule message goes through an entire serialization and deserialization process which results in a new Mule message with the same payload.

Read about the effect of transport barrier on a mule message here.

When one would prefer to use a VM transport over a flow reference?

One case would be that VM endpoints enable message redelivery strategies to be configured in your exception handling blocks – this is not possible with flow-refs.

VMs can do this because they internally use a queue to hold messages while flow-refs are similar to simple method calls.

Difference between flow, sub flow and private flow in MuleSoft

2017-07-27T06:15:00.000-05:00

All three Flow types can be referenced from a Flow Reference component.

Flow is a message processing block that has its own processing strategy and exception handling strategy. Used in integration tasks, data processing, connecting applications, event processing, etc.

Subflow always processes messages synchronously but inherits processing strategy and exception handling strategy from the calling flow. It can be used to split common logic and be reused by other flows.

Private flow does not have source define. It can be synchronous or asynchronous based on the processing strategy selected. Also, they have their own exception handling strategy. Allows you to define different threading profile.

====

Processing strategy

While sub-flow is always synchronous the private flow behavior depends on the processing strategy

Performance

Sub-flow has a better performance when using request-response exchange pattern as they are actually a new processor chain injected in the flow at configuration time. Private flows are instead useful for asynchronous call provided you configured their processing strategy properly

Exception strategy

Private flow: the exception will be trapped by the local ES the exception will not be propagated to that main flow.

Sub-flow: will use the exception strategy defined in the main flow and it will have the exception got in the sub-flow.

Message Properties

In both case all properties, regardless their scope, are preserved from the main flow.

Threading profile

Private flows: allows you to define a different threading profile, but if you don't they will use the default one, not inherit the invoking flow one

Sub-flows: they will share the parent flow threading profile configuration

Overall

Sub-flows run within the same execution context (exception handler, transaction, properties) of its main flow, while private flow will initiate a new execution context.

To summarize, sub-flow is always recommended except in the case the exception needs to be handled in a separate flow different from the main flow or you are implementing an asynchronous pattern

Agile Methodologies

2017-07-27T01:03:00.000-05:00

Agile Methodologies

SCRUM
XP - Extreme Programming
LEAN KANBAN
CRYSTAL
Dynamic Systems Development Method (DSDM Atern)
Feature Driven Development (FDD)
Agile Project Management (APM)
OpenUP

Agile Concepts

Tools and Techniques

PMI-ACP Exam Content (7-Domains)
1. Agile Principles and Mindset
2. Value Driven Delivery
3. Stakeholder Engagement
4. Team Performance
5. Adaptive Planning
6. Problem Detection and Resolution
7. Continuous Improvement

Tips, Tricks, Strategies and Tools

Agile adoption leads to effective scaling and faster delivery

Take up more projects and deliver faster

PMI - Agile Certified Practitioner (ACP)

Agile

Customer requirements and solutions evolve through the repeated cycles of planning, collaboration and delivery
Iterative and Incremental (Evolutionary)
Meets changing needs of stakeholders
"Just Enough Ceremony" - means creating only those documents that justifies the requirement.

Agile Best Practices

Face to Face communication
Shorter Development cycle
Business and Developer Collaboration
Working software as the primary demonstration of progress
Effective Engineering Practices
Frequent demonstrations of progress and early ROI
Inspect and adapt to business changes
Retrospectives and continuous improvement

Agile Core Principles and Practices

Early Delivery of Value through Iterations with Demos
User Stories reflect Business Value and Priority
Continuous Involvement of the customer
Acceptance Tests for all Requirements
Retrospectives
Sustainable Pace or Velocity
Communication
High Visibility

Scrum Learnings

2017-07-27T01:02:00.002-05:00

Three Pillars of Scrum

Transparency
Inspection
Adaptation

Scrum Team & Roles (comprises of FIVE to NINE members 7+-2 excluding the SM & PO)

Product Owner
Scrum Master
Development

Key Terms

Product Backlog

All work to be performed in the foreseeable future, both well-defined and that requires further definition

Sprint

period of 30 days or less within which a set of work will be performed to create a deliverable

Spring Backlog

A well-defined requirement that can be worked on with little change,
over 30 days or less,
resulting in a tangible, potentially shippable incremental deliverable

Scrum

A daily meeting at which progress and impediments to progress are reviewed

- Release Backlog (Shortlisted prioritized items ready for a Sprint execution)

- Visibility and Velocity

Scrum Meetings

Sprint Planning
Daily Stand-Up Meeting
Sprint Review
Retrospection

XP - Extreme Programming

2017-07-27T01:02:00.001-05:00

respond to high cost of changing requirements; and
establish strong engineering practices to improve software quality

XP introduced revolutionary concepts, such as:

Test Driven Development;
Continous Integration;
Iterations; and
User Stories

Five Core Principles of XP

Communication
Simplicity
Feedback
Courage
Respect

XP Practices

Fine-scale feedback

Pair-Programming
Planning Game
Test-Driven Development
Whole Team

Continuous Process

Continuous Integration
Refactoring or design improvement
Small releases

Shared Understanding

Coding standards
Collective code ownership
Simple design
System Metaphor

Programmer Welfare

Sustainable pace

AnyPoint Studio 7 Beta

2017-07-27T01:02:00.000-05:00

These are some of new features and improvements in Studio 7 beta:

* Improved palette which enables users to more quickly discover what they’re looking for by searching directly for operations and saving favorites.
* Users can now explicitly manage which connectors and modules are associated with a project.
* Connectors and modules are now managed directly by Anypoint Studio, and do not require users to manage update sites.
* Easily navigate to code from visual view by right clicking on a component and clicking “View XML”
* Maven is now embedded out of the box inside Studio. Additionally, every project now has a Maven POM, making it easier to incorporate projects into CI/CD systems.
* Flows and scopes are now collapsable.
* Updated icons make flows easier to read.
* DataSense metadata is now stored in a human readable format this is easier to share, commit and merge.
* Support for importing API specifications from Design Center
* Improved user experience for connector and modules
* Simplified experience to manage credentials when logging into the Anypoint Platform

Amazing Wireframing Tools & Apps

2015-02-24T21:39:00.002-06:00

Web

Mockingbird – Wireframes on the fly
Simulify – Interactive, shareable wireframes, mockups and prototypes
Solidify – Create clickable prototypes
Concept.ly – Convert wireframes and designs into interactive apps.
ClickDummy – Turn mockups into clickable prototypes
Creately – Real time diagram collaboration
Lumzy – Mockup creation and prototyping tool
Cacoo – Diagrams with real time collaboration
Mockflow – Great design tools and collaboration services for designers
Mockup Designer – Basic wireframing tool hosted on GitHub
dub –Denim – DENIM is an outgrowth of the original SILK project, a pen-based sketching tool for designing user interfaces.
fluidIA – A free open source project for prototyping open source projects.
Justinmind – Nice wireframing platform for web and mobile apps.
UXPin – It puts everything to your fingertips but is a costly tool.
RWD Wireframes – Wireframing tool for responsive layouts
Gliffy – Drag & Drop from library to anywhere on page, creating wireframes easily.
Wireframe.cc – Free tool for creating quick mockups.
Pencil Project – This is a free and easy to use open source tool for creating GUI prototyping.
Wirify – Converting web page to wireframe is just a click away with wirify.
Axure RP – Premium wireframe tool for detailed wireframe creation.
PowerMockup – Convert power point to wireframe.
JustProto – Premium tool with drag and drop feature to create highly interactive prototypes.
FlairBuilder – Premium tool for easy creation interactive wireframes.
WireframeSketcher – Instantly creates wireframes, mockups and prototypes for desktop, web and mobile applications.
Serena Prototype Composer – Build simple, high fidelity prototypes that look like the real thing.
Balasmiq – You can come up with a design and iterate over it in real-time in the course of a meeting.

Android

Framer – Modern prototyping tool
Indigo Studio – Rapid, interactive prototyping
Lucidchart – Simplest and most powerful flowchart software in the world.
Frame Box – Easy, simple wireframing
Mockups.me – Create and present interactive UI wireframes
Grafio – Grafio is a custom modifiable app.

iOS

LovelyCharts – Diagramming app with desktop and mobile versions
Tiggzi – The only cloud-based platform with visual development tools and integrated backend services
Realizer – Interactive presentation prototypes
iPhone Mockup – Free basic iphone Mockup tool.
iMockups for iPad – Premium wireframing and mockup app.
Antetype – Wireframing and prototyping desktop application for Mac.
iMock – Good app for creating mockups, more features could be added.
JumpChart – Architecture, layout and content planning
Mockup Builder – Super-easy prototyping and mockups
Live Wires – wireframe & prototype your iPhone and iPad app concepts quickly.
AppCooker – AppCooker is a good tool to bring iOS applications to life.
UI Sketcher for iPad – Sketch, refine and share user interface ideas rapidly.
Mockabilly – iPhone mockups with genuine iphone behavior
Blocks – Create annotated HTML prototypes
UX Toolbox – Create, document and share wireframes and prototypes
Moqups – A free tool for making high resolution SVG mockups and wireframes.
ProtoShare – Good tool for website wireframing.
JustinMindPrototyper – Fantastic prototypes for web and mobile apps.
Pidoco – Quick premium prototyping for web apps, mobile and enterprise apps.
OmniGraffle for Mac – Creates excellent graphic documents.
HotGloo – Easy and beautiful way to create mockups.
Sketchypad – Easy-to-use interface for creating websites and soft interfaces.

SQL vs MongoDB Terms

2015-02-18T02:44:00.001-06:00

SQL Terms/Concepts	MongoDB Terms/Concepts
database	database
table	collection
row	document or BSON document
column	field
index	index
table joins	embedded documents and linking
primary key Specify any unique column or column combination as primary key.	primary key In MongoDB, the primary key is automatically set to the_id field.
aggregation (e.g. group by)	aggregation pipeline

SQL Terms, Functions, and Concepts	MongoDB Aggregation Operators
WHERE	`$match`
GROUP BY	`$group`
HAVING	`$match`
SELECT	`$project`
ORDER BY	`$sort`
LIMIT	`$limit`
SUM()	`$sum`
COUNT()	`$sum`
join	No direct corresponding operator; however, the`$unwind` operator allows for somewhat similar functionality, but with fields embedded within the document.

R Programming

2015-02-12T19:56:00.004-06:00

R is a language and environment for statistical computing and graphics.

For more information please refer to http://r-project.org

For Big Data Analytics

Who Uses R?
- Spreadsheet Users
- Programmers
- Statisticians
- Data Scientists

RStudio for R

Will update more information as I learn R...

Android Project Build and Deployment Process steps

2015-01-25T00:31:00.000-06:00

Android Version History

2015-01-24T12:30:00.002-06:00

Android Version History

Alpha (1.0)
Beta (1.1)
Cupcake (1.5)
Donut (1.6)
Eclair (2.0–2.1)
Froyo (2.2–2.2.3)
Gingerbread (2.3–2.3.7)
Honeycomb (3.0–3.2.6)
Ice Cream Sandwich (4.0–4.0.4)
Jelly Bean (4.1–4.3.1)
KitKat (4.4–4.4.4)
Lollipop (5.0–5.0.2)

1 Pre-commercial release versions (2007–2008)

2 Version history by API level

Key Mobile Challenges

2015-01-24T12:18:00.002-06:00

Key Mobile Challenges
- Low Processing Power
- Limited RAM
- Intermittent, Low bandwidth, High Latency data connections
- Impact on battery life

Hadoop Hive External vs Internal Table

2014-05-15T01:06:00.001-05:00

Hive tables can be created as EXTERNAL or INTERNAL. This is a choice that affects how data is loaded, controlled, and managed.

Use EXTERNAL tables when:

The data is also used outside of Hive. For example, the data files are read and processed by an existing program that doesn't lock the files.
Data needs to remain in the underlying location even after a DROP TABLE. This can apply if you are pointing multiple schemas (tables or views) at a single data set or if you are iterating through various possible schemas.
You want to use a custom location such as ASV.
Hive should not own data and control settings, dirs, etc., you have another program or process that will do those things.
You are not creating table based on existing table (AS SELECT).

Use INTERNAL tables when:

The data is temporary.
You want Hive to completely manage the lifecycle of the table and data.

Hadoop Quick Info

2014-05-14T03:47:00.002-05:00

Apache Hadoop– Hadoop is an open source software framework which allows you to cheaply store and process vast amounts of structured and unstructured data.

Flume– A service for collecting, aggregating, and moving large amounts of log and event data into Hadoop.

HBase- A scalable, distributed, column-oriented data store that runs on top of HDFS. A short video overview of Flume.

HDFS– an acronym for "Hadoop Distributed File System"

Hive- A data warehouse infrastructure built on top of Hadoop for providing data summarization, query, and analysis. It allows you to query data using a SQL-like language called HiveQL (HQL).

HiveQL (HQL)- A SQL like query language for Hadoop used to execute MapReduce jobs on HDFS.

JobTracker– the service within Hadoop which distributes MapReduce tasks to specific nodes in the cluster.

NameNode– the core of the HDFS file system. The NameNode maintains a record of all files stored on the Hadoop cluster.

Oozie - workflow scheduler system to manage Apache Hadoop jobs.

Pig– a high level programming language for creating MapReduce programs used within Hadoop. An introduction to Pig.

Sqoop– a tool for transferring data between Hadoop and relational databases.

YARN– a resource manager for Hadoop 2. YARN is short for "Yet another resource negotiator". Introduction to YARN on the Apache Hadoop website.

ZooKeeper - Centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services.

Visual Studio and Browser Link Feature

2014-04-03T11:44:00.001-05:00

Announcement made today in Build 2014.

Visual Studio and Browser Link Feature

You can EDIT the Styles/Javascripts loaded in browser using the Browser's developer Tools (which we launch by pressing F12).

As you EDIT, you can see the changes made inside the Visual Studio code base and also other browsers (say chrome) getting auto-refreshed with the changes made in another browser Developer Tools.

Azure Web Jobs

2014-04-03T11:41:00.001-05:00

Announcement made today in Build 2014.

Now we can run Web Jobs as part of Windows Azure Websites and run as background jobs (calling queues, etc...)

Need not spin up a new VM or new cloud services to run the background jobs, instead create Web Jobs as apart of Windows Azure Websites.

Rethink - 2 in 1 User Experience

2014-04-02T01:01:00.002-05:00

I liked this video explaining about “Rethink Navigation for 2 in 1s”

- Explaining Easy, OK, Hard to hit areas on Mobile, Tablets & Touch screen laptops.

Check this link for a 5 minutes video explanation à http://software.intel.com/en-us/articles/2-in-1-user-experience?utm_source=Smashing_Magazine_Noupe&utm_medium=Banner_Ads&utm_campaign=2-in-1_UX_Campaign

Research Analysis

Positioning of the main Navigational elements of your App on these device variations

Commerce Server 10.1 Setup on Windows Server 2012

2014-02-18T12:05:00.000-06:00

In this blog post i am documenting the steps required to install and configure Commerce Server 10.1 on Windows Server 2012 machine.

List of downloads i did from http://commerceserver.net/

Launch CommerceServer-10.1.67.0 setup file (note: version may vary in future).

Splash screen of Commerce Server 10.1 installation

Accept the Licence Agreement page

Installation in progress

Commerce Server Configuration Wizard. Click Next

MSCS_Admin DB configuration

Add a new user "CS_RunTime"

Configure Staging Service to run with CS_RunTime user

Commerce Server Configuration summary

Commerce Server Configuration - In Progress

Commerce Server Configuration - Completed

Commerce Server Setup - Completed

Post installation of Commerce Server 10.1 on Windows Server 2012 we can now see in the Metro UI following apps are added

Docker Overview

2014-02-05T12:35:00.001-06:00

In this post, I will document the learning I had with Docker.

Container History

- Linux Containers

Open VZ

Single patched linux kernal ability to use architecture kernel version of system for executing the container

Linux V-Server

Virtual Private Server implementation. Created for adding OS level virtualization to the linux kernel itself.

What's a Container?

OS level Virtualization.
Kernel of OS allowing multiple isolated user space instances instead of one.
Like real server from point of view of operator.

What is Docker?
Docker is an open-source project to easily create lightweight, portable, self-sufficient containers from any application. The same container that a developer builds and tests on a laptop can run at scale, in production, on VMs, bare metal, OpenStack clusters, public clouds and more.

Technology behind Docker

Developed using Google's Go language
with Linux kernel using cgroup & cnames (namespace)
AUFS union filesystem
LxC (Linux containers)

TB typed more...as i learn...

Android Layouts

2014-01-19T01:14:00.003-06:00

In this blog post, i am documenting at high-level the leanings i had on the Android - Layout Types

Linear Layout (Aligns its child elements in single direction one after another)

Horizontal Layout
Vertical Layout

Relative Layout

Align's child elements relative to its sibling or parent. Help to avoid nested linear layouts.

Frame Layout (Allows child views to put on top of one another child views)
Table Layout (Aligns elements in Row & Column format)

More TB typed...

Powershell commands

2014-01-03T11:56:00.000-06:00

This post i am documenting some of powershell quick reference scripts

Get Members of a command
c:> get-service | gm

Get-help CMD-NAME
Example:
c:> get-help start-service

Get-process -name "Name"
Example
c:> get-process -name "outlook"

Get Process - physical directory path
PS C:\Windows\system32> get-process outlook | dir

Directory: C:\Program Files (x86)\Microsoft Office\Office14

Mode LastWriteTime Length Name
---- ------------- ------ ----
-a--- 3/31/2011 4:08 PM 15933792 OUTLOOK.EXE

c:> get-service -filter * | select -Property name, @{name='ComputerName',expression={$_.name}_