Let’s start with the SSD!

Replaced my hard disk with Samsung QVO 860 1TB. This is one of the most economical options. Selecting the right SSD can be quite complicated(form factor[M2, add-in, SATA, etc.] and type of storage[SLC, MLC, TLC, and QLC]). You can refer to this amazing article by Tom’s Hardware to select one.

Now let’s quickly discuss the migration process. We would need a SATA-to-USB cable to get started. We can either install a fresh copy on the SSD by first formatting it in the Mac OS Extended format and then restarting the MacBook in the recovery mode. Otherwise, we can use SuperDuper app which allows us to clone our hard disk.

The last step left is to replace the hard disk. A screwdriver set would be needed to open up the MacBook. I used this screwdriver set. Please check this video which shows in a step-by-step manner to remove the old HDD and install the SSD.

Anything left? Oh yeah! one last bit. We need to enable TRIM. And what’s that? SSDs works much differently than regular HDDs. TRIM improves the efficiency to manage garbage collection. Install Chameleon SSD Optimizer.

Following are the suggested settings for Chameleon SSD Optimizer:

1. Enable TRIM
2. Disable Sleep Image
3. Set Sleep Mode to 25
4. Turn off the Sudden Motion Sensor (SSD doesn’t have any moving parts)

Now let’s bump up the RAM

If we were to believe the Apple website then the maximum RAM is 8GB for MacBook Pro Mid 2012 but across the internet geeks have installed 16GB without any issue. Please refer to this page which lists the maximum RAM supported across different MacBooks.

Anything else?

1. We can add another SSD by removing the DVD Writer. We would be needing a hard drive caddy(height: 9.5mm). In case, if we need a lot of storage then this is quite handy.
2. These methods can deliver similar results with a Windows laptop.

After months of reading about design thinking, I delivered my first session to 14 kids(age: 10 to 15 years old) at their survival camp in Dehradun. Need to thank my friend Ravi Dabbiroo for inviting me. The kids came from The Integral School, Hyderabad. They were divided into three teams and assigned a task to design an alarm clock for a blind person. I hope the results would astonish you:

What is design thinking?

A design methodology that provides a solution-based approach to solving problems.

Design thinking really provides us a proper framework for structuring our ideas and bring them to life. It starts with the most important concept of empathy. We can only solve a problem when we empathize with those suffering from the problem.

So are you really interested to kickstart your journey into design thinking? Following are a few resources to get started:

1. Creative Confidence by Tom and David Kelley – A brilliant book to start
2. d.school at Stanford – Lots of resources to get started
3. The Node Chair – A classic case study of design thinking

I hope the above resources shall give you enough to initiate your journey. The best part being it works for everyone irrespective of one’s background and nature of job.

Ever wondered what’s the problem statement for Uber. The most common answers that I’ve received were in the lines of convenience, comfort, and transparency of commute whereas for Uber it’s the ways to reduce the idle time(the time between a passenger deboarding and a new passenger boarding) for a cab. Around this problem statement, a different set of technologies are used to design the solution.

Now let’s talk about the problem statement for Flipkart or Amazon. The most common answers lie in the range of varieties of a product, convenience of shopping, and trackable shipping. Essentially Amazon or Flipkart is like courier companies and their prime problem statement is to increase the effectiveness of their warehouses.

Finally, what’s common between the problem statements of Uber and Flipkart? Idle Resource Utilization. Now if we’re to treat; idle resource utilization as a yardstick then we realize that Airbnb is also doing the same thing.

A startup could be solving multiple problems but clearly selecting the one carrying the most relevance at an early stage helps in gaining momentum leading to eventual success. Many times, it is advised to place the human in the centre of problem-solving to forge effective solutions.

I’m hopeful that this post gave you some enlightenment regarding the role and importance of a problem statement. Looking forward to hearing your responses and views.

Lesson 1: User gets the first preference

Any product is essentially built for a target audience but what if that user isn’t kept in the center of all discussions. The biggest issue of not keeping the user in the center creates more problems than solving one. A product moves from the phases of useful(solves a problem like a painkiller), usable(empathizes with the user), and desirable(user enjoys the process).

Lesson 2: Technical prowess isn’t that crucial to start

Airbnb started with a simple WordPress blog to start their initiative and today they’ve around 100 mobile engineers(Jun 2018) in a company of fewer than 5000 employees. Facebook started with PHP in 2004 and later in 2014 created a dialect of PHP titled Hack. Also, created a virtual machine called HHVM(HipHop Virtual Machine) for improving the performance and stability. Data-driven decisions instill overall stability to a product and the company; could’ve facebook thought of the same in 2004. Only use that much amount of technology which solves the purpose.

Lesson 3: Where’s your failure framework?

Thomas Edison had failed a thousand times before creating the electric light bulb. Obviously, Bell didn’t invent the telephone in a one-shot process. When great scientists with huge experience and knowledge took years to create something then what are we afraid of? The only thing is to start fast and fail fast. The missing part of the puzzle is reinvesting the learnings from a failure. Remember the reason for solving the problem was the non-existing solution and that would take time. Also, remember the effectiveness of a solution does make a big difference to stay ahead from copycats.

Lesson 4: Die in a team than survive in isolation

In any team, there will always be differences but the whole team can stay in sync with the problem statement(how might we make the experience better). Irrespective of the role played by a team member they can think and empathize with their end-user. If you’re leading your team then ask yourself whether the potential of all the members is correctly utilized?

I hope these lessons give you some context and give you a slight push to question the ways things are currently solved at your workplace. Next time before embarking on a treacherous journey with some heavy technologies, ask yourself, are you eating your pastry with a shovel?

Recently I got a Nexus 7(2013) WiFi tablet and out of curiosity wanted to install WhatsApp Messenger. There are plenty of methods available online which requires either rooting or installing the messenger through the APK file.

Thanks to WhatsApp Web we can access it on our tablet! Let’s see how to achieve it:

Step 1: Open Google Chrome on your tablet

Step 2: From options menu, tick the Request Desktop Site. 

Step 3: Open web.whatsapp.com

Step 4: Scan the QR Code using your phone having your WhatsApp

Step 5: Now you can access your WhatsApp Messenger simultaneously on your tablet and phone

I’ve prepared a video with the screenshots. Do check it out

This Infographic is produced by Coupon Audit (provides Shoebacca coupon) and Shubhamoy’s Blog

Use the following code to embed this infographic on your website/blog:
[html]
This Infographic is produced by Coupon Audit (provides Shoebacca coupon) and Shubhamoy’s Blog[/html]

Phase 1: Installation & Configuration

Installation is pretty simple but still I’ve added it for the fulfillment of this article.

For Windows Users: The following URL will guide you to install MongoDB and configure it for working with PHP.

[box type=”info”]www.pronique.com/blog/installing-mongodb-on-windows-the-wamp-way[/box]

For Linux Users: The following URL guides to install MongoDB based on the flavor used.

docs.mongodb.org/manual/tutorial/install-mongodb-on-linux/

The following is a set of commands to add the PHP driver for MongoDB on a Linux box.

[shell]
sudo yum install php-pear| sudo apt-get install php-pear
sudo yum install php-devel | sudo apt-get install php-devel
sudo pecl install mongo
sudo echo ‘extension=mongo.so’ >> /etc/php.ini
[/shell]

Phase 2: Working with MongoDB Shell

Working with MongoDB shell is seriously fun. Following are some of the basic commands to start with:

[shell]
> show dbs //Displays the list of database
> use //Selects a database
> show collections //Displays collections inside a database
> db..find() //Displays all the records inside a collection
[/shell]

The following code snippet helps in adding a user with password and set of roles to a database for authentication purposes.
[shell]
> use
> db.addUser( { user: “”, pwd: “”, roles: [ “readWrite” ] } )
[/shell]

For correctly assigning roles to a user, the following link is quite helpful.

[box type=”info”]docs.mongodb.org/manual/reference/user-privileges/[/box]

We can also pass scripts written in simple javascript for interacting with the MongoDB shell. Following is a piece of code for adding a user “sadmin” with password “blog” with default privileges.

[javascript]
//Source Code of Mongo_addUser.js
db = db.getSiblingDB(“shubhamoy”); // Selects or Creates the Database
db.addUser(“sadmin”, “blog”);
[/javascript]

Phase 3: Working with PHP and MongoDB

The following PHP function would return all the entries of the “emps” collection in the descending order.

[php]
public function getAllEmployees()
{
$m = new MongoClient(“mongodb://scott:tiger@localhost:27017/employee”); //MongoDB Connection with Authentication on default port
$database = $m->selectDB( “employee” ); //MongoDB Database Selection
$db = $database->emps; //MongoDB Collection
$result=$db->find(array(), array(“empno” => 1,”name” => 1, “deptno” => 1, “manager” => 1))->sort(array(“_id” => -1)); //Query
return $result;
}
[/php]

The main issue faced by developers coming from SQL background is with writing queries. QueryMongo.com allows to generate MongoDB queries from traditional MySQL queries. It is quite useful for understanding the basics though I won’t suggest it for advanced or real-world applications instead refer the MongoDB Documentation for writing advanced queries.

MongoDB can be easily integrated into CodeIgniter. Check out this repository for smooth integration  of MongoDB with CodeIgniter github.com/alexbilbie/MongoQB

Phase 4: Working node.js and MongoDB

Recently I was working on writing a HTTP Proxy server with node.js. It gave me an opportunity to integrate it with MongoDB. So we only need the MongoJS library for integrating MongoDB with node.js.  Following command will install the MongoJS module for node.js

[box type=”info”]npm install mongojs[/box]

Following are some snippets to start your work:

[javascript]
var m = require(‘mongojs’); //Include MongoJS Module
var db = m(‘myDB’); //Selects myDB Database
var contact = db.collection(‘contact’); //Selects contact Collection
contact.insert({name: name, age:age}, function(err, doc)
{
console.log(“Record Inserted Successfully”);
});
[/javascript]

For more examples and sample code snippets. Check out: github.com/mafintosh/mongojs#usage

Acknowledgement

1. Abhishek Gahlot: The guy who introduced MongoDB and whose article(link) was quite useful in writing this article.

2. MongoDB Group on Facebook facebook.com/groups/mongodbgroup/

Recently while working on a newspaper’s website, I was wondering that what if all the content is lost since how much can we trust the cloud; is a big question? I ended up writing a script which would dump the MySQL database and would create a final archive with the content and database dump. Finally this archive is transferred to another server.

Now this script also has many limitations and issues but at least solves the purpose. The main focus is to handle some uncertain situations and secondly implementing a backup script on a server isn’t a rocket science but at least helps us prepare to handle a disaster.

[box type=”info”]

VPS Backup Script

[/box]

Finally I would like to request everyone to suggest more functions to the backup script as well as try installing it on their servers. In today’s world to actually create a difference one only needs to follow some basic tricks of trade which does the magic. Happy Coding

]]> https://www.shubhamoy.com/disaster-management-for-a-web-developer/feed/ 0 https://www.shubhamoy.com/android-development-101/ https://www.shubhamoy.com/android-development-101/#comments Mon, 03 Sep 2012 19:17:11 +0000 http://www.shubhamoy.com/?p=1155 Read more]]> Recently I had attended a conference EMERGE OUT Delhi by NASSCOM. One of the speaker in the conference was Mr. Rajan Anandan who is the Managing Director of Google India! His best words were, if you want to be a successful in next 2-3 years then switch to mobile application development and as a company if you wish to become a millionaire or billionaire then hire 100 mobile application developers. His words motivated me a lot and forced me to start learning mobile application development.

Let’s find out that how can we actually start diving deep into learning Android:

1. developer.android.com

This website is sufficient for someone to learning android app development. It acts as a guide which covers from soups to nuts of android development. It also has a training feature where step by step methods are used.

2. TheNewBoston Channel on YouTUBE (Thanks to Abhishek Gahlot for sharing)

As per Mr. Anandan in the coming times, 90% of a website’s content will be video. Since every likes watching a video. So the above mentioned channel has 200 videos for dedicated android training.

The above mentioned resources are more than sufficient for someone who wish to learn android.

Kindly check the following presentation on design and development of mobile apps since mobile app development is different from native app development.

1. Site Hosted on a Vulnerable Server: Most of the times a WordPress site gets attacked just because of a vulnerable server since WordPress is highly secured from various attacks. So running after cheap web hosts isn’t a good decision.
2. Badly Configured WordPress Installation: Most of the times the site isn’t properly configured in terms of security which leads to many exploits.

Now let’s consider a attack scenario to understand the topic in a better way:

An attacker first of all attacks the most vulnerable site hosted on a server. After that he simply uploads a script known as shell and tries to traverse the whole server, which results in access to many websites. Most of the times a SymLink Attack is done to get access to all the domains hosted on that particular server. This results to access the wp-config.php file of any site using WordPress. Now the attacker gets access to the database and simply adds a new user to the database or modifies the password of the present user. Finally he logs into the admin panel and modifies any theme or plugin with the shell and thus gains full access.

Now we have sufficient information to repair a WordPress Installation. Let’s divide the cases:

Case 1: The homepage is showing something inappropriate and we can’t log into the admin panel

Step1: Access PHPMyAdmin and check the wp_users table. If no values are present then move to Step 2 else move to Step 3

Step 2: Execute the following queries:

[HTML]

INSERT INTO `databasename`.`wp_users` (`ID`, `user_login`, `user_pass`, `user_nicename`, `user_email`, `user_url`, `user_registered`, `user_activation_key`, `user_status`, `display_name`) VALUES (‘1’, ‘myblog’, MD5(‘password’), ‘John Doe’, ‘info@johndoe.com’, ‘http://www.johndoe.com/’, ‘2012-06-07 21:03:00’, ”, ‘0’, ‘John Doe’);

INSERT INTO `databasename`.`wp_usermeta` (`umeta_id`, `user_id`, `meta_key`, `meta_value`) VALUES (NULL, ‘1’, ‘wp_capabilities’, ‘a:1:{s:13:”administrator”;b:1;}’);

INSERT INTO `databasename`.`wp_usermeta` (`umeta_id`, `user_id`, `meta_key`, `meta_value`) VALUES (NULL, ‘1’, ‘wp_user_level’, ’10’);

[/HTML]

Step 3: If the table wp_users and wp_usermeta has values then the delete all the records and then move to Step 2.

Step 4: Remove all other index.html or index.php files and create a index.php in the root with the following code:

[PHP]

<?php

define(‘WP_USE_THEMES’, true);

require(‘./wp-blog-header.php’);

[/PHP]

Step 5: Your installation should work fine, if still you find some error then check another case.

Case 2: We can’t log in to the Admin Panel and the site working fine

Step 1: This means that someone has simply deleted the username or changed the password.

Step 2: Access PHPMyAdmin and access the wp_users table, if the user is available and all the other values like email, etc. are correct then execute the following query:

[HTML]

UPDATE  `database`.`wp_users` SET  `user_pass` = MD5(  ‘password’ ) WHERE  `wp_users`.`ID` =<your user id>;

[/HTML]

Step 3: After successfully logging into Admin Panel, kindly change your password once again since WordPress has a flaw, i.e., it stores salted passwords but work with simple MD5 Hashed password.

There can be many other cases but mainly the above two solves the issue unless someone hadn’t deleted the whole database. Finally here’s a list of things to do for future protection:

1. Delete all the files of WordPress installation except the wp-content folder
2. Upload the wp-admin, wp-includes and root files from latest WordPress archive
3. Upload the Emposha’s PHP Shell Detector and scan for any shell script
4. Finally run the installation and follow the steps mentioned in this article

 This brings us to the end of this article and I guess that next time when someone’s WordPress installation is attacked then he/she should be able to repair on its own. Now if you’ve any types of questions then please proceed. Even I can assist you as well.