Git Training: Introduction to Git — Distributed Version Control System

Why version control system or SVN?

• Allows to store more than 1 version of the code base
• Working with same code at different places at the same time
• TFS is centralized version control system
• Centralized & Distributed VCS
• CENTRALIZED
• Repository will be stored in centralized DB
• Entire repository is stored in a central machine
• Accessing A repository from multiple workspaces and to be connected to 1 machine which maintains and manages the commit, changes, history at 1 place
• Disadvantage: you need separate server and local repo setup
• DISTRIBUTED
• Ever user will have its own local repo
• Ever user will have its own workspace
• While syncing with other users you need to PULL / FETCH
• This user need to be necessary to connected to central machine.
• Code to be written ono local repo and as per desire push / pull / fetch for sharing code with different users working in the team
• Git and GitHub is different !
• Git is version control system, no centralized machine required
• GitHub as Hosted VCS, it is a provider for Git.
• It has hosting platform for VCS
• No local sever required
• Private / Public repos
• Public repos are FREE and are exposed to general public, anyone having absolute URL can access the Repo. Ideal for open source projects
• To access Private repos you need to have GitHub subscription. It comes with a paid subscription with minimum $9/month. Only team / collaborators can access. Ideal for closed source projects (not sharing code with external parties)
• Know about the Security standards that GitHub holds
• Goto GitHUb.com search for VS Code, use node.js framework called Electron install the VS Code and build your version of VS Code IDE
• Common terms:
• Repository
• Can be Public / Private
• Every repo will default branch as “master”, it gets created every time to create new repo
• Repo represents owner, team, collaborators, source code
• GitHub User
• Branch
• A parallel version of the repository
• Allows to work freely without disturbing original
• Ever repo has a “master” branch
• Branches can be created from existing branches
• Collaborator
• With read and write access to repo, able to pull and push code
• Not a owner but invited by Owner
• Additionally Holds permissions of a collaborator
• Contributor
• Not an owner or collaborator
• Contributes to projects by accepting pull requests and merging
• Clone
• Copy of repository in local system
• Git clone command to clone repo
• Commit
• Like check-in in TFS environment
• Fork
• Remote to Remote
• Creating copy from other repository, writing your wrapper around it and release your own project separately
• Mostly used in open source projects
• Push
• Merge changes of local repo to remote
• Requires authentication for both public and private repos
• Anonymous access is not allowed
• Pull
• To sync local with remote repo
• Fetch and merge
• Pull-Request
• Notifying Collaborators to review and merge the Code to the DEV branch or any other branch
• Fetch
• Merge
• Git checkout master (branch)
• Git checkout <<branch name>>
• Git merge develop (branch)
• Before pushing code to repository GIT runs algorithm knows your CI and notifies if there is conflict in the code which being pushed
• Managing / storing versions
• Restore previous version
• Backup
• Track changes
• Helps to identify What changes happened to your code or your code is going through since it has been written and released to the server

Working with Repositories

• Learn to Sign up and create public repository
• Git clone <<remote repository URL>>
• Git clone add <<file name>>
• Git commit <<file name>> (this commits to local repository)
• Git push (to push local changes to remote repository), it will ask for username and password
• Stage and unstage commit from Visual Studio code version control
• Git commit -a -m
• Git status
• Git fetch (fetches the data) + git merge (to merge in local repo)
• Working directory and actual committed directory are different

Working with Branches

• Feature branch
• Hotfix branch
• Bug fixes
• Whenever you create a local branch, git also creates a reference of the local branch on remote repository
• Environment Branching strategy
• GEP is using this methodology
• Release, DEV, Master, Hotfix
• Hotfix > Master
• Feature > DEV
• Release > QC or UAT
• Create feature branch from DEV branch
• Create Hotfix branch from Master branch or depending from which branch the fix has to merge to Master
• Release branch will be in sync with strict Release schedule
• Resolving Merge Conflicts

Better team Collaboration

• FORK
• Share repo model