Git Fundamentals

This is a summary of the commands covered in the Git Fundamentals course by Fabio Biondi & Giorgio Boa.
Link: https://fabiobiondi.teachable.com/p/github-fundamentals

1. Git-GitHub Fundamentals
2. PRO TIPS
3. Remote Repository
4. Branch
5. Rebase
6. Tag-Release
7. Pull-Request
8. Git-Stash
9. Bonus

GIT-GITHUB FUNDAMENTALS

After registration on GitHub, create a repository. Then, we can create and commit files directly on GitHub if necessary.

Setting up

Open cmd and type:

• git config --global user.name yourusername
• git config --global user.email youremail

Login and clone

From August 2021 GitHub has the ability to authenticate via password for all operations carried out, for example from Command Line or Desktop Applications.
Two solutions are now available: 1) Token-based authentication 2) the use of SSH Token Based Authentication
The simplest option (and recommended by Github) for the new authentication process is to use a "personal access token" (PAT) via HTTPS.

Documentation: https://docs.github.com/en/authentication/keeping-your-account-and-data-secure/creating-a-personal-access-token
Flow

---

To verify that the local folder is connected to the GitHub's remote repository we can use the command :

• git remote -v git status git commit -m "first commit" --> option "-m" is used to add a comment

git commit: best practices

• 20/30 characters max, (50 max in some case)
• start with a lowercase letter
• separate commit for every feature/fix
• no punctuation marks at the end of commit
• imagine to write after the sentence "if applied, this commit will.."

---

PRO TIPS

COMMAND	DESCRIPTION
git log	allows you to analyze the local history of our commits
git log --online	compact versione of "git log" ("q" to exit from the log)
git log --online --all	compact versione of "git log" ("q" to exit from the log) with commit of all branches
git log --grep="style"	searching commit with a specific string
git log --invert-grep --grep="style	searching commit without a specific string
Alias on Windows: insert alias in gitconfig (file in C/Programs/Git/etc)
in this example "git lg" will make a "git log"

COMMAND	DESCRIPTION
git restore --staged .	remove ALL changes (with ".", or instead a specific file) from STAGING AREA
git commit -am "comment"	make add and commit in one command
git commit --amend -m "changing commit message"	change last commit message
git commit --amend -m "changing commit message and adding new file"	add change at the last commit (before is necessary "git add." )
git commit --no-edit	commit without messagge or default message
git restore --staged <file>	remove files from STAGING AREA
git reset HEAD <file>	remove files from STAGING AREA
git diff origin/main HEAD	watch differences from LOCAL COMMIT and REMOTE COMMIT (origin=alias remote repo, main=remote branch HEAD=name of the commit)
git reset HEAD~1	remove n LOCAL COMMIT(reset default mixed option), files returned in WORKING AREA(in this example: from HEAD, return 1 commit before)
git reset hash	remove to n LOCAL COMMIT with hash, taked with "git log --online"(reset default mixed option), files returned in WORKING AREA
git checkout HEAD -- .	all files will revert to their original state, to the last commit
git reset --soft [HEAD~n][HASH]	remove n LOCAL COMMIT, files returned in STAGING AREA
git reset --hard [HEAD~n][HASH]	remove n LOCAL COMMIT, files will be deleted
git reflog	after a "git reset --hard ..", if you need to watch all actions on the project. Then, taked the hash, you can restore with "git reset --hard hash"
git revert [HEAD~n][HASH] (":wq" after the git command)	undo remote repo to local repo
git reset --hard [HEAD~n][HASH] + git push --force	delete last n LOCAL COMMIT and REMOTE COMMIT
git rm --cached (file/folder name) [-r]	delete files/folders from REMOTE REPO (option -r if folder with files internally)

git ignore

*.env	ignore all files with "env" extension
node_modules	ignore folder with thah name

REMOTE REPOSITORY

command	description
git branch	return the branch of the your repo
git push -u origin master	first push to allineate local repo with remote repo
git push
git pull

BRANCH

in Git, a branch rapresents a temporary line. It is already created once the project is initialized. During new developments, it's possible to create new branches for new feaures.

command	description
git branch	return the branch of the your repo
git branch branchname	create new branch
git branch -M main	rename branche name with "main"
git checkout branchname	switched to branch "branchname"
git branch -d branchname	delete branch "branchname"
git checkout -d branchname	create and switched to branch "branchname"
git merge branchname	merge with "branchname"

Conflicts with remote repositories on different files

Suppose we have committed on a branch "detached" from main, which we will call "new_branches" : after the branch change (returning to "main") we will make git merge
Now, another person commits to ANOTHER file on the main branch of the remote repository - the git push command will not work. So we have to do a git pull to download the latest changes, and now we could make the git push.

Branch diagram with "lg" alias

In the file gitconfig, put in the section "alias": lg = log --color --graph --pretty=format:'%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' --abbrev-commit --branches
With this command we can see the branch diagram.

Conflicts with remote repositories on same files

Suppose we have committed on a branch "detached" from main, which we will call "new_branches" : after the branch change (returning to "main") we will make git merge
Now, another person commits to the SAME file on the main branch of the remote repository - the git push command will not work. So we have to do a git pull to download the latest changes, but now the IDE that we're using will ask what changes we want to take. Once time that we have choose, now we could make the git push.

Create remote branch

command	description
git push origin new_branch	orgin is the alias of remote repo

Delete remote and local branch

command	description
git branch -d branchname	delete local branch
git push origin --delete branchname	delete remote branch

REBASE

What is the rebase command? It is used to rewrite the history(commit) of our project.

command	description
git rebase -i [HEAD~n][HASH]	take the last n commit or the commit with that hash, then we have many options (type a to go to insert mode)
reward	replacing pick with option r, then with :wq (to save) we can edit the commit message. Then :wq yet.
squash	replacing pick with option s, then with :wq (to save) we can merge more commit and edit the commit message. Then :wq yet.
fixup	replacing pick with option s, then with :wq (to save) we can merge more commit like squash but CAN'T edit the commit message. Then :wq yet.
drop	replacing pick with option d, then with :wq (to save) we can drop the specific commit selected. Then :wq yet.
edit	replacing pick with option e, then with :wq (to save) we can edit files. Then with git add .. Once time we finished, type git --amend [-m "optional commit"][--no-edit]. Finally git rebase --continue
git rebase -i [--root][HEAD~n][HASH] --exec "node index.js"	to execute and print results of file "index.js" from root, before type :wq

MERGE VS REBASE

Suppose we have a "main" branch, and one "feature" branch, and we are in main branch :

• with merge (git merge feature), the changes will be integrated subsequently with another commit;
  
  MERGE MAIN INTO FEATURE
  

• with rebase, (git rebase feature), takes our commit of the feature branch and put them in head of main branch;

TAG-RELEASE

The command TAG let us to create a simil branch but it's in read only, it is used when people wants to release new version.

command	description
git tag	to see how many tags we have in history
git checkout v.1.0	switched to tag "v.1.0"
git tag -a v.1.0	let to create a tag with name "v.1.0", after confirm, cmd will ask us a description, finally :wq to exit
git tag -a -f v.1.0	create a tag with force option
git -d v.1.0	delete tag
git tag v.1.0 [HASH]	associate tag to old commit (hash from git log --oneline)
git push origin v.1.0	sync local tag with remote tag

Create a release

The concept of "tag" belongs to git, while "release" to remote, in this case to GitHub

1. Draft a new release in Code section of your GitHub repository, to create a new release
2. Choose a created tag, or create it, the same for branches
3. Write the tag name
4. Optional description and attachments
5. Publish or Save draft

PULL-REQUEST

It's a request that we make inside a project (that could my public/private project or project of another author). So, we can include code inside our project or we can propose a change inside a repository of an other author on GitHub.

With the command forklet us to clone a project of an other author and associate it with us. So, we create the same project in our repository to be able to modify it later and make the pull request.

Open a pull-request on GitHub:

• go to the repo that you want to edit
• now edit, create new file or something that you want to do
• make the commit with the click on "Commit" or "Commit new file"
• in the main page of repository now we have a button called "Compare & pull request", click that
• in the new page we can have all the options for the pull request
• once time that it's ready, click on "Create pull request" or "Create draft pull request" (for draft)

Close a pull-request on GitHub:

• go to the page with open pull requests
• click on "Close pull request"
• it's possible to reopen the request with the button "Reopen pull request"

GIT STASH

command	description
git stash save my_stash	This command allows you to "put aside for later" the changes made to our code, without committing them, so that it is possible, therefore, to go back to the last local "commit" and, if necessary, modify branches if necessary.
git stash -u	the untracked files too
git stash list	to see the list of stash
git stash show	to see the content of last stash
git stash show stash_name	to see the content of "stash_name", taked by git stash list
git stash pop	allow us to apply the first change of the list we have put aside
git stash pop stash_name	allow us to apply the specific change we have put aside
git stash apply stash_name	make the same of pop but it doesn't delete the stash
git stash drop [stash_name]	delete the last/specific stash
git stash clear	delete all stashs
git stash save stash_name -u git stash branch branch_name stash_name	create a stash, then take a stash and copy in a (new) branch

BONUS

command	description
git diff my_new_branch	verify diff to my branch(the branch you are in) and the other branch(my_new_branch)
git diff	pending changes in the current branch
git diff > file_diff	extract off git diff in a file
git diff [HASH][HASH]	diff between the 2 commits
git bisect start, git bisect bad HEAD, git bisect good [hash]	find bugs and regressions
```git bisect HEAD [hash]	the same uf commands above, but in one command (the first parameter is the bad commmit, the second is the last good commit)
git bisect log	log of bisect
git bisect bad	we are saying that the current commit is bad
git bisect good	we are saying that the current commit is good
git bisect reset	I go back to the initial situation

Deploy static website (HTML, CSS, JS) on GitHub Pages

1. Go on your repository on GitHub, "Settings", "Pages"
2. On "Source" options, select the branch that you would you like to deploy, and click on "Save"

Your static website is online.