We all know that git is unavoidable in the world of modern software development (YES we do!) and often am I asked how to get started with it. Well...who actually knows? git can get as complicated as you want it to be, But it also can be very simple if you just want to get stuff done. There are a lot of tutorials already and I am too lazy to reinvent anything (RTFM).
What I want to do here is to give you a quick overview of the most important commands and concepts (like, real quick) and then point you to some resources that I found helpful. We will do this in a tutorial (-ish) style (I don't usually do that) so you can follow along if you want to.
You are hired as a software developer at a company that uses git for version control but you just left that cave you were living in for the last 10 years and have no idea what git is. You are a bit scared because you need that job to sustain your home-made bitcoin mining rig and your collection of 90s anime figurines. Also you use windows even though the process is almost the same on linux and you are not rich enough to own a Mac. But don't worry, I got you.
First we do some reading so we do what every good developer does and google "git tutorial". One of the top results is from here. which is good because it is the official documentation (RTFM). It's also where you can download git for your OS.
While it's downloading we sum up what we know so far: Basically git is a tool that helps us to keep track of changes in our code (oversimplified). It does this by creating a history of changes (commits) and storing them in a tree-like structure (branching). It also allows us to work on different versions of our code at the same time (merging). We can also share our code with others (remotes) and work on it together (pulling and pushing). That's it. We are done with the minimum of theory required.
Now that git is installed and correctly set up
you started to work on your first task.
Create a new folder and name it "git-gud". Open a terminal in that folder. If you don't know what a terminal
is, well....google it. Now type git init and hit enter. You just created a git repository.
Git creates a hidden folder called ".git" in your current directory. This is where all the magic happens and you don't have to worry about that folder. Just remember that deleting it will delete your local repository.
Now create a file called "README.md" and write something (anything) in it. Save it.
As we just created a new file we have to tell git that we want to track the changes we make on it.
We do this by adding it to the staging area. Type git add README.md and hit enter.
You can check the status of your repository by typing git status and hitting enter.
It shows you all the tracked and untracked files and the current branch you are on
(don't worry about branches for now).
Now we want to save our changes. We do this by creating a commit. you will do that a lot.
Type git commit -m "my first commit" and hit enter. You just created your first commit.
The -m flag is used to add a message to your commit. It is required and you should always
add a meaningful message to your commits. It will help you and others to understand what
changes you made (no for real, write good commit messages). You can check things again with git status.
To see all your commits type git log.
Now you are a master of local git repositories. You can create, add, commit and check the status of your repository.
Your boss wants to see what you did so far and you can't send him your computer. He said "just send me the github link". Your boss just assumed that you already have a github account. No need to tell you to google what github is, right? So now you know it is a platform to share your code with others and collaborate on it. You are done with the hassle of backing up your code on a usb stick or on a cloud drive. Also you already created an account and set up git (RTFM).
Now you want to push your code to github. First you have to create a repository on github (yes another one). You can do this by clicking on the plus sign in the top right corner and then follow the instructions. usually you want to give it the same name as your local repository (git-gud) and make it public so your boss (and the whole world) can see it. After creating your remote repository with no files in it github explains many ways to add files to it.
We will use the one that says "push an existing repository from the command line". So once again follow
the instructions. You will have to type git remote add origin <url> in your terminal and hit enter.
The url is the one you get from github when you create a repository. The scheme is basically
https://github.com/<username>/<repository-name>.git.
git branch -M main is used to rename the default branch from "master" to "main" (because reasons).
Now type git push -u origin main and hit enter. You just pushed your code to github.
Refresh the page and you should see your code there. just like that you can share your code with others.
Everytime you make changes to that readme file, commit the changes and push the commit using
git push. (Go ahead and try it)
You can also check the status of your remote repository by typing git remote -v. There you can see a
new word "fetch". It is used to get the changes from the remote repository to your local repository.
Let's say your boss made some changes to the readme file from his own computer (don't worry about how for now)
and now he pushed those changes to the remote repository. You want to get those changes locally.
You do this by typing git fetch and hitting enter to check if there are any changes.
Then you type git pull and hit enter to get those changes.
Now you can see the changes by typing git log.
To simulate this you can go to your github repository and edit the readme file from the browser.
Then commit the changes and push them to the remote repository. Now you can fetch the changes locally
from your terminal typing git fetch and hitting enter. You can see the changes by typing git log.
Then you can pull the changes by typing git pull and hitting enter. Check the readme file
and you can witness the magic.
Now you unlocked the power of git and github. You can create, add, commit, push and check the status of your local and remote repositories, also fetch and pull changes from the remote repository.
Your boss didn't fire you yet even though it took you 3 days to write two lines to a readme file. He want you to add a new file called "newbs.md" to your repository. But yesterday you were drunk and you deleted the whole repository from your computer. C'mon get in the context and delete the repository from your computer (yes the whole git-gud folder. Also being drunk is not mandatory).
Now you can just clone the repository from github to your computer. That's how cool github is.
Type git clone <url> in a terminal wherever you want to keep your repository and hit enter.
The url is the same as before. You can find it on the github page of your remote repository.
You can also do it from the browser by clicking on the green "code" button and follow instructions.
Anyway, now you have your repository back on your computer. You can check the status by typing git status.
Now proceed to create the "newbs.md" file and add it to the staging area. Then commit the changes.
Then push the changes to the remote repository. You can check the status of your remote repository
to make sure the changes are there.
If you successfully followed along you should now have a basic understanding of git and github. But wait, there is more. You can do a lot more with git. We just scratched the surface. We didn't even talk about branching, pull requests, and merging, which are vital for safe and efficient collaboration. Whenever your boss decide to hire more people this will come handy. Also we didn't talk about gitignore which prevent your drunk self from pushing your bitcoin wallet to github. And we didn't talk about rebase which is a very powerful tool to keep your commit history clean and readable. Also submodules, stashing, resetting and reverting your mistakes, cherry-picking, reflog, bisect, and blame to find out who is pushing bad code to your repository, Also hooks which are used to automate things...
Just RTFM!!
I hope this was helpful. I tried to keep it simple and short. This article is not meant to be a complete guide to git. It is just a quick overview of the most important commands and concepts for the 2 or 3 people who asked me how to get started with git. I hope you enjoyed it.
The actual repository I created while writing this article can be found on my github
here. If you have any questions or suggestions
open an issue on this very same repository. I will try to answer them as soon as possible.
Also if you got gud enough at git and github and want to make your "first pull request"
you can do it on this repository. Just open a pull request that adds your github
username and link to "newbs.md" and I will be happy to merge it. Just see how I did it and add yours
to the bottom of the list.
Remember that the only way to actually git gud is to keep trying and learning.