Learn Github && Git in an afternoon (Beginners) 🐱‍💻☁️

Github

Is a platform where you can put your code in a cloud git repository completely free and where other developers could see your code and contribute or use it.

Github is very useful and is used by a lot of developers in the world. This tool could allow you to improve as developer and be atractive to software companies.

• A Github account. Create one here
• Git installed on your PC. Learn Git
• Follow me on Github 🐱‍🏍🎯

Click on it and you'll see this page:

This page is very intuitive, but I'll explain the elements on it:

• Repository name: Is the name wich the people will see in your repositories list, find a cool and explicative one.
• Description: Here you'll explain the project in a few words. Maybe you could write the objective or the tech used on it.
• Public/Private: If you want to show your repo to other developers, set public (recommended). If you want to keep the project only for you, set private.

The following 3 options can be skipped for now, we just have to click on create repository button:

Now, We have done our repository successfully, we'll see something like this:

Don't worry if you don't understand what that is, we'll see about it in the next steps. For now, you just need to know that you have your first Github repository! 🐱‍👓

Okay, the following is an example local repository with 3 files and few commits:

We have to upload or push our local repository to the Github repository, is like sync both. For this we have to do the following:

Do you remember the github page of our new repository? there we found this commands:

git remote add origin URL_EXAMPLE
This git command allow you to add a new remote repository (URL) to your local repository, that means that you could upload your commits (push), update your local repository (pull) and more.

In this case, we're adding a new remote URL_EXAMPLE with the alias origin.

git branch -M main
This command change the branch name of our repository to "main". The reason of the change is because by default git names the branch "master" and Github need a branch named "main" (to avoid racial discrimination of master and slave).
The branch concept needs a more complete explanation to be understood, but for now isn't necesary, just see it like the main name of this repository.

git push -u origin main
This is the interesting thing.

• The git push command allow us to push (upload) our commits to the github repo.
• The origin main indicates that we want to push the changes to the remote named "origin" (setted on the first command) and the branch named "main" (setted on the previous command)
• The -u is an option to set the origin main options to default on the future git push/pulls calls.

Now we know what this commands are for, so we can type them on the terminal an check the results:

(When you enter the last command a window will open and it will ask you to login to Github, just enter your account and password and continue. This will happen only 1 time)

If you refresh the repository page, you'll see your files and you could check interesting info like the commits made, the languages used on the repo and it's description.

Finally, we'll have our repository on Github! And the best part is comming! In the next sections you'll learn what things you can do with Git and Github.

First, we'll make some changes:

Then, add the changes and commit it:

Now, we can get the repository log (history) to see the new commit:

As we can see, the new commit was made successfully. But this commit is only in the local repository, and it need to be pushed to the Github repo.

For this, we can type one of the following commands:
git push
or
git push origin main

Both work fine, the difference is that the second one declare explicitly in wich "remote" and "branch" the commits will be pushed. And the first one just take the default settings.

(If you rememeber, this "remote" and "branch" default settings was been setted in the previous section on the git push -u origin main command, thanks to the -u option) 🤯

When we enter one of this commands, we'll get:

Now, if we go to the Github repository page again and refresh it, we'll see our new commit(s) 😎.

To clone a repository we have to know some things:

• We need the real URL of the repository wich we want to clone. For get it, we have to go to the github repository page and copy this:
  

• We can clone whatever public repository that we want, this means that we can go to the page of any repository of any user and copy it's link and clone it on our pc, this is awesome 🤩 because we are able to download every open source code , for example we can go to the oficial Microsoft Visual Studio code repository, clone it, change it's code and modify it as we want 🧨

For this example, we'll clone this Example repository. So, go and copy it's URL.

Now, we have to open a terminal and go to the folder where we want to clone the repo:

In my case, I want to clone it in D:\personal-projects> folder.

Now we just have to type this command:
git clone https://github.com/JAFB321/devto-learn-github.git

We'll get something like this:

This should have created a new folder called like the repository cloned. In this case, the folder is D:\personal-projects\devto-learn-github.

Then this folder will have all repository files:

Now we can open a terminal on this folder and type git log --oneline or git status to check the new local repository:

Now we can make changes and commit them as we want. But, can we push this new commits to the original Github repo? 🤔 In this case, you won't be able to do that, Why?🤨 because the repository isn't yours, you don't have permission to push changes to repositories that you aren't the owner (or where you don't have explicit access).

For get permission and do that, we have 2 options:

• Request write access to a Github repository to the owner.
• Make a copy of the Github project on your own Github repositories or Fork a project.

Both options are material for another tutorial, we won't see them in this one.

Obviously, if you clone a repository wich you're the owner (like the repo that you created on the first sections) you are able to push your changes to the Github repo without problem.

To update the desktop pc repository, you must pull the new changes from the Github repo.

How to solve the problem

To do that, we'll clone one of our Github repo 2 times in our pc.
We'll create 2 folders to clone the repo 1 time on each folder:

We have 2 copies of the same Github repository on our pc. I cloned my own repository but you must clone one of your own Github repos (for example the repo you created in first sections).

Now, we'll make some new commits on the example-repo1:

And push them:

Note that you don't need to type -u origin main because is a cloned repository, and these options were set in the cloning process automaticaly.

Once this is done, we have the Github repository and example-repo1 updated, but example-repo2 is outdated because it doesn't have the 2 last commits.

To update example-repo2 we need to pull this new commits from Github repo. For that we have to type one of the following commands on the terminal in example-repo2 repo:

git pull
or
git pull origin main

Both work fine, the difference is the same of the git push command where origin main are the "remote" and "branch" explicity defined.

When we enter one of these comands, we'll get:

The elements inside blue rectangle are the changes summary of the commits downloaded. If we run git log --oneline we'll see these new commits:

Now we have the 2 repositories updated and ready to work 😎. But take care about pull and push your commits on 2+ copies of the same cloned repository, because if you make different local commits on each repo separately and try to push them at same time you could get a merge error 🌪️, but don't worry there is an easy solution for those kinds of problems wich we'll see on future Git tutorials 🐱‍🏍.