If you are a developer, chances are you have heard about git and github or gitlab. If you want to become a developer git is necessary skill that makes your profile astounding.

Git is essential for

tracking your developer journey
getting involved in open-source culture
gaining practical knowledge by contributing to real world projects

So, habituate to git before you close your lid. Make this time to learn git

Installation & Setup

Install Git from here & configure with credentials

Git (a software): Git is a version control system used for tracking changes used for source code management in software development.

Github (a service): Serves as a host for Git repositories to store their code in a centralized location

Commands

Command	Description
git init	Initializes a new Git repository
git add	Adds files to the staging area
git status	Used to check the state of the staging area, as well as the working directory
git log	Used to view the entire commit history
git commit -m "message"	Used to commit files (locally) on repository
git clone	Used to download existing code from a remote repository
git branch	Used to list all the local branches on the machine
git merge	Merges the provided branch with the current working branch
git branch	Used to create a new branch locally
git branch -d	Used to delete a branch
git branch -m	Used to rename the current working branch
git checkout	Used to switch from the current branch to another one
git push	Used to save all commits to the remote repository
git checkout -b	Create a new branch and switches to the new one
git pull	Used to pull down all the updates from the remote repository
git rm	Used to remove a file from the working directory
git stash	Used to temporarily remove uncommited changes
git reset	Undo the changes to the local files and restore to the last commit
git diff	Displays the difference between files in two commits or between a commit and your current repository

Git Workflow

git workflow.png

Demonstration

Initializing a new repository

Before you initialize a new repository, first change current directory into the project folder and run the command below

git init

A git init will initialize your project folder as a Git repository by generating a hidden folder .git inside your project folder. This .git folder contains all essentials needed for version controlling your new project.

Status of repository

git status

Files could be in one of four states

Untracked State: files that are not yet being tracked and managed by git
Modified State: files that are being tracked and managed by git and made changes
Staged State: modified files that are prepared to be introduced to git with pending commit
Committed State: files that are already commited.

Staging files

Staging a specific untracked or modified file

git add <filename>

Staging all the files in a repo, both untracked and modified files

git add .

. period here represents the project-name

Commit files

git commit -m "this is a commit message"

-m specifies message to the commit which is optional

If you want to work on hosted projects the below are used extensively

Cloning repositories

use git clone to create a copy of the original project which mostly would be hosted on Github, Gitlab or some other cloud code hosting platform.

git clone <repository-url>

Creating, listing, renaming & deleting branches

Branching makes it possible to explore other ways to write a functionality without messing with the main code that we implemented or already implementing.

We can create our own branch -> make changes -> open a pull request. Then the project maintainance team would merge our branch to their main branch. This flow open doors for many developers to work simultaneously on a single project.

Creating a new branch

git branch <branch-name>

Listing all branches

git branch

Listing remote branches

git branch -a

Renaming an existing branch

git branch -m <old-branch-name> <new-branch-name>

Deleting an existing branch

git branch -d <branch-name>

Deleting an existing branch even when the branch has not fully been merged in its upstream branch

git branch -D <branch-name>

Checking out branches

Checking out is the term used when we change our Git HEAD from one branch to another

Checkout from main branch to a our-branch

git checkout <branch-name>

Checkout a branch that is non-existent using flag -b on git checkout to checkout from your current branch into a new non-existing branch

git checkout -b <new-branch>

Unstagging changes

Often useful

Move every staged files back into your working tree

git reset

Move only specific staged files back into your working tree

git reset <file1>[, <file2>, <file3>, ...]

Move only staged files in a given folder

git reset <folder-name>

Reset commit history

Often we commit changes that are isn't necessary or done by mistake. In such case we can reser the commit by

--hard to delete latest commit

git reset --hard

commit hashes can get from git log command. Used to reset to a particular commit

git reset <commit-hash>

Push local changes to upstream repository

git push <remote> <branch-name>

eg: git push origin main

Pull changes from the upstream

It is common that local clone diverges or lags behinds the upstream repository in commit history. Without updating local repository with the new commits on the centralized upstream, any pull request we make could result in a merge conflict during merge into the centralized repository.

To resolve this issue we use pull to synchronize local repo with centralized upstream.

git pull <remote> <branch-name>

This cleans up your commit history by removing the common merge commit message

git pull --rebase <remote> <branch-name>

Commit history

we can use git log to view commit history

all commit history for a project.

git log

commit history from a specific author or committer

git log --author <author-name>

commit histories having a certain text

git log --grep <search-string>

revision history after a specified date

git log --after <date-string>

revision history between a date range

git log --since <date-string> --until  <date-string>

Experience working of Git by this awesome simulation tool learngitbranching.js.org

Hope this helps and suggest you to use git in regular. Meet you soon with another awesome blog post 😉✍️JrNet

Git and Github [guide for developers]

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