Git Tutorial

1.Introduction

Version Control System (VCS)

A version control system (VCS) allows you to track the history of a collection of files. It supports creating different versions of this collection. Each version captures a snapshot of the files at a certain point in time and the VCS allows you to switch between these versions. These versions are stored in a specific place, typically called a repository

$E:\Users\satyacodes\Pictures\12.png$

We have 3 types of version control systems

Localized version control systems
Centralized version control systems
Distributed version control systems

1. Localized version control systems
A localized version control system keeps local copies of the files. This approach can be as simple as creating a manual copy of the relevant files.
Examples: Revision Control System (RCS) Source Code Control System (SCCS)

2. Centralized version control systems
A centralized version control system provides a server software component which stores and manages the different versions of the files. A developer can copy (checkout) a certain version from the central sever onto their individual computer.
Examples: Subversion (SVN), TFS

Both approaches have the drawback that they have one single point of failure. In a localized version control systems it is the individual computer and in a centralized version control systems it is the server machine

3. Distributed version control systems
In a distributed version control system each user has a complete local copy of a repository on his individual computer. The user can copy an existing repository. This copying process is typically called cloning. Every clone contains the full history of the collection of files and a cloned repository has the same functionality as the original repository.

Typically, there is a central server for keeping a repository but each cloned repository is a full copy of this repository.

Examples : GIT, BitBucket, GitHub

$E:\Users\satyacodes\Pictures\12.png$

Introduction to GIT

Git is a distributed version control system, founded in 2005 by Linus Torvald.we can Setup GIT in our machine by downloading it from below links

Git configuration

git config command allows you to configure your Git settings. Git stores all global configurations in .gitconfig file, which is located in your home directory

Setting username: This information is used by Git for each commit.
[SmlCodes_Admin]$ git config --global user.name "Small Codes"

Setting email id: This information is used by Git for each commit.
[SmlCodes_Admin]$ git config --global user.email "admin@smlcodes.com"

Git Basic Operations

$E:\Users\satyacodes\Pictures\12.png$

`git init` – Create a new repository

Every Git repository is stored in the .git folder of the directory in which the Git repository has been created. This directory contains the complete history of the repository. The .git/config file contains the configuration for the repository.

We use the git init command to create a Git repository in the current directory

kaveti_s@HYDPCMCSTS MINGW64 /e/Users/devops/Repos
$ mkdir LoginDemo

kaveti_s@HYDPCMCSTS MINGW64 /e/Users/devops/Repos
$ cd LoginDemo/

kaveti_s@HYDPCMCSTS MINGW64 /e/Users/devops/Repos/LoginDemo
$ git init
Initialized empty Git repository in E:/Users/devops/Repos/LoginDemo/.git/

kaveti_s@HYDPCMCSTS MINGW64 /e/Users/devops/Repos/LoginDemo (master)
$ git status
On branch master

Initial commit

nothing to commit (create/copy files and use "git add" to track)

`git add` – Add a new file to the repo

In LoginDemo repo I want to add 3 files -index.jsp, signup.jsp, login.jsp.

$E:\Users\satyacodes\Pictures\12.png$

We use git add command to put a snapshot of the file to the staging area.

1.Adding single file to Stage
=========================================
Syntax : git add <file-name>
Example: git add index.php
 
2.Adding files of same type
=========================================
Syntax : git add -<wildcard>.<extension>"
Example: git add -*.jsp"
 
3.Adding all files at a time
=========================================
Syntax : git add .


kaveti_s@HYDPCMCSTS MINGW64 /e/Users/devops/Repos/LoginDemo (master)
$ git status
On branch master

Initial commit

Untracked files:
  (use "git add <file>..." to include in what will be committed)

        index.jsp
        login.jsp
        signup.jsp

nothing added to commit but untracked files present (use "git add" to track)

kaveti_s@HYDPCMCSTS MINGW64 /e/Users/devops/Repos/LoginDemo (master)
$ git add .

kaveti_s@HYDPCMCSTS MINGW64 /e/Users/devops/Repos/LoginDemo (master)
$ git status
On branch master

Initial commit

Changes to be committed:
  (use "git rm --cached <file>..." to unstage)

        new file:   index.jsp
        new file:   login.jsp
        new file:   signup.jsp


kaveti_s@HYDPCMCSTS MINGW64 /e/Users/devops/Repos/LoginDemo (master)
$

`git commit` – commiting changes

git commit command will Stores the current contents of the index in a new commit along with a log message from the user describing the changes.

Syntax : git commit -m "<message>"

`git log`

git log command will Shows the commit logs.

kaveti_s@HYDPCMCSTS MINGW64 /e/Users/devops/Repos/LoginDemo (master)
$ git log
commit 08032d113ef458a2783da26464d91881449e14a1
Author: Kaveti Vs Satyanarayana <Kaveti_S@ad.infosys.com>
Date:   Thu Jul 13 17:56:33 2017 +0530

3.Remote repositories

We created a new empty repository in BitBucket called LoginDemo

$C:\Users\kaveti_S\Desktop\temp.PNG$

`git remote`

Now our code is ready in local system, we have to add this into newly created bitbucket repo. For doing this we need use git remote command

kaveti_S@HYDPCM90480L MINGW64 /d/Repo/LoginDemo (master)
$ git remote add origin ssh://git@localhost:7999/jav/logindemo.git

`git push`

Now we conncted with remote repo. To place these files in Remote repository we use git push command

kaveti_S@HYDPCM90480L MINGW64 /d/Repo/LoginDemo (master)
$ git push -u origin master
Counting objects: 5, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (5/5), done.
Writing objects: 100% (5/5), 800 bytes | 0 bytes/s, done.
Total 5 (delta 0), reused 0 (delta 0)
To ssh://localhost:7999/jav/logindemo.git
 * [new branch]      master -> master
Branch master set up to track remote branch master from origin.

Now code is Pushed into remote repository. $C:\Users\kaveti_S\Desktop\temp.PNG$

`git clone`

git clone is used to checkout the remote repository & create a working copy of a local repository.

Syntax: git clone /path/to/repository

kaveti_S@HYDPCM90480L MINGW64 /d/Repo
$ git clone ssh://git@localhost:7999/jav/logindemo.git
Cloning into 'logindemo'...
remote: Counting objects: 5, done.
remote: Compressing objects: 100% (5/5), done.
remote: Total 5 (delta 0), reused 0 (delta 0)
Receiving objects: 100% (5/5), done.

`git pull`

git pull is used for check the changes on our remote repository and pull down if any new changes exist.

Syntax: **git pull origin **

kaveti_S@HYDPCM90480L MINGW64 /d/Repo/logindemo (master)
$ git pull origin master
From ssh://localhost:7999/jav/logindemo
 * branch            master     -> FETCH_HEAD
Already up-to-date.

4. Branching

Branches are used to develop features isolated from each other. The master branch is the “default” branch when you create a repository. Use other branches for development and merge them back to the master branch upon completion.

$C:\Users\kaveti_S\Pictures\temp.png$

1.Introduction

Version Control System (VCS)

Introduction to GIT

Git configuration

Git Basic Operations

git init – Create a new repository

git add – Add a new file to the repo

git commit – commiting changes

git log

3.Remote repositories

git remote

git push

git clone

git pull

4. Branching

`git init` – Create a new repository

`git add` – Add a new file to the repo

`git commit` – commiting changes

`git log`

`git remote`

`git push`

`git clone`

`git pull`