GitHub- Source Code Version Control Work Flow- Basics

In this blog I am planning to explore some of the key futures of Git. Git is useful when we are trying to develop code in distributed manner, independent and off the network. GitHub is a web-based repository hosting service, it provide flat from to save your code for open source projects. GitHub provides services through Web GUI, Command Line tool and Desktop tools. In this blog I am focusing on GitHub Desktop futures.  

     1.       Git Background:

•  Git is an open source project which is compatible with most of the operating systems like Mac, Linux, and Windows.
•  It’s a distributed version control system, aimed at speed, data integrity. 
•  Git is an independent of network and central server.
•  Every git directory on every computer is a full-fledged repository with complete history and full version-tracking capabilities.

     2.       GitHub account:

If you don’t have a github account create it using: https://github.com/

Note: The free version of github account creates repository open for all, if you’re looking for secured/private code management you have to choose the paid version.

     3.       How to install Github on Desktop:

Download exe file from https://desktop.github.com/

Run the exe file it will take few minutes to check Internet connectivity.

After github desktop install we should be able to see Git Shell, GitHub tools in your All programs. In this blog I am planning show how to use GitHub and manage your code.

Note: Provide your name and email address which we have created in #2, which enables you make commits on repository.

     4.       Creating a new git project on Desktop:

     4.1. We can create repository as shown below:

Once the git repository is created we will can see .gitattributes, .gitignore files. There are three specific reasons to create these ‘.git*’ files.

     a.       If the folder is empty git will be recognize the folder.

     b.       A .gitignore file update with the file types which git has to ignore during its operations.

     c.       A .gitattributes file is a simple text file that gives attributes to path names.

     4.2. We can drag and drop the complete folder on to github desktop which folder has your project files, it will create git repository under the same folder: 

Note: Git doesn’t make any changes to your folder, it just creates some hidden files/folder to track your file changes.

     4.3. How to add a new file/file updates/remove files in to your git repository:

If you have new file/file changes in your repository folder you can provide ‘Summary’ and ‘Description’ to commit your changes to your local git repository using ‘Changes’ tab. Description is optional. 

How to remove/rename a file: Let’s say that Demo_Test_Rename.scala has been renamed to Demo_Test.scala. GitHub recognize these changes like this:

a.  File renamed – GitHub understading file has been deleted and a new file has been created.

b. File Deleted – GitHub understanding is file has been deleted.

 Note: Without first commit you can’t push your local repository to host (github.com).

     4.4 How check your commits: Using History you can see your commits, based on your comments and date & time of commits we can identify your commits.

     4.5. SHA-1:  It’s a very important future of git. A SHA is a hash algorithm checksum to compare added & commit files/file changes. SHA algorithm generates a 40-hexadecimal string, it’s a unique identifier to identify each commit on your repository.

Note: In the above GitHub Desktop screen shot SHA contains only 7 characters. Since we have very less commits and we can identify uniqueness of commit using less than 10 characters it been shown as 7 character string. If we can look at the log from GitSheel, we will be able to see the 40 character string OR we can copy and past it to see 40 character string.

     4.6. How to compare file changes:

Now let’s say that we are making some changes to “LineCount.scala” and committed it to our local repository. We can compare it and see what changes has been made from our commit.

4.6.1.        Comparison between your working directory and git repository:

You can find the difference between your working directory and git repository easily from ‘Changes’ tab as shown below:

Here I just split the comments line in to two lines from one line. GitHub identifying these changes with ‘–‘ and ‘+’.  

4.6.2.        Comparing changes between two commits:

In our repository we have to commits 41431abf38639dd01a077a5c33b9d046b9bf35fb and 28b7e310a79e036ca296c1de48da4f6aa1b4b8d5 its changes can viewed at:

     5.       How to create a new GitHub.com repository from GitHub Desktop:

Click on Publish à provide your details and Publish & do initial commit. 

     6.       Cloning a new project:

We can close repository in two ways:

     6.1. Cloning a Github.com repository from Github.com:

Open your repository and click on “Set up in Desktop” and select the folders to create repository.

Now we can see GitHub.com repository on your GitHub desktop:

     6.2. Cloning a Github.com repository from GitHub desktop:

Go to your desktop top right corner and click on ‘+’ à ‘Clone’ à select the repository to be cloned. Then select folder when you would like to create local repository. 

Now we can see GitHub.com repository on your GitHub desktop:

     7.       How to syncing your changes:

Let say that you’re working on A-ZinHadoop repository using GitHub Desktop. Once your changes are successful you can Push your changes from GitHub Desktop to https://github.com/repository using Sync option.

     8.       Branches: A Branch can be created to implement your new ideas without creating storage overhead and without impacting other branches code. At the same time other members can work on master/new branches to collaborate changes. Once the idea is successful we can merge it with master branch.

Note: Before creating a branch your current branches changes should be committed and clean.