git

ECHO $(WHOAMI)

№Ball

太空三

Todays slide

Before that

git --version

What is git?

Let's assume that you have a program.

Called FinalProject

How do you often store your data?

FinalProject_V1
FinalProject_V2
FinalProject_V3
FinalProject_V100000000
FinalProject_FINAL

How do you often store your data?

FinalProject_V1
FinalProject_V2
FinalProject_V3
FinalProject_V100000000
FinalProject_FINAL
FinalProject_FINAL2
FinalProject_FINAL3
FinalProject_FINAL10000

What if you are trying to cooperate with classmates?

FinalProject_V1_EVIL
FinalProject_V1_STAR
FinalProject_V1_TSAI
FinalProject_V1_MERGE
FinalProject_V1_MERGE2
FinalProject_V1_MERGE3

Moreover

Do you even know the different between V4 and V1?

Moreover

What if someone changed and somehow the program just doesn't work where CRTL+Z doesn't help you?

What is git?

A version controller

How to git?

As a master said before

you can make great products from an application by only using 20% of its functions.

You only need to know the basics

Basic `STAGES` of git

Basic `STAGES` of git

Working Directory -> Where you write your code
Staging Area -> Magic
Local Repo -> git on your computer
Remote Repo -> git not on your computer

What is a Repo?

Repository which you can see as a project file (often a directory)

Review

What is the stage that you write your codes?

Working Directory

mkdir gitPractice # Make an new directory
cd gitPractice # Go to the directory

Working Directory

Creating one

git init

Result

Initialized empty Git repository in $(pwd)/.git #you can do "echo $(pwd)" to verify if the command is correct

Go ahead an play make changes

echo "Never Care U" > NCU # This will create a file called `NCU` with content "Never Care U"

Quick Review

After finishing a period, what stage will you want to enter

Staging Area

OFTEN USED COMMAND

git status

Results

What branch are you on
Untracked (Unstaged) files
Staged files

Staging Area

OFTEN USED COMMAND

git add .

. stands for everything
you are able to only add certain files

git add NCU

Staging Area

OFTEN USED COMMAND

git status

Any differents?

Quick Review

After staging a file, what will you want to do?

Local Repos

Which is commit.
This means to put all the thing from stage into your repo, and telling what have you done or why do you do this.

Before that

We need a GOOD convention of commit so that we know what you are writing

A COMMIT SHOULD

<type>[optional scope]: <description>

[optional body]

[optional footer(s)]

type -> need to discuss before using, however it often contians and can be more of them
- FIX
- ADD
- FEAT
- DOCS
- TEST

A COMMIT SHOULD

<type>[optional scope]: <description>

[optional body]

[optional footer(s)]

scope -> sometimes we don't need them, but when we are in a big project, it will give a better view of what the error is
description -> the reason you make this commit
body -> further descriptions if needed
footer -> References

A COMMIT SHOULD NOT

BE NONSENSE

Trust me, you will find out that this is hard.

Let's try shell we?

OFTEN USED COMMAND

git commit

RESULT

[master (root-commit) 6d13e9f] ADD: add NCU for demostrating how to commit.
 1 file changed, 1 insertion(+)
 create mode 100644 NCU

Let's see if it works

OFTEN USED COMMAND

git status

RESULT

On branch master
nothing to commit, working tree clean

What if we have a typo?

Go ahead and do something else to your file

echo "Nobody Cares U" > NCU  # This will overwrite `NCU` with content "Nobody Cares U"

Let's check status again

OFTEN USED COMMAND

git status

RESULT

On branch master
Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
        modified:   NCU

no changes added to commit (use "git add" and/or "git commit -a")

We just don't need that much descriptions

git commit -m "FIX: typo of NCU"

Now we know how to create files to repo

How to see the changes and what happens is the most important thing.

LOGS

git log -> repo's history
git reflog -> whole git history

Give it a try!

git log

RESULT

commit 9b605fe216228416f4b999f34c17d05f33f33ef1
Author: N0Ball <cwj0325@g.ncu.edu.tw>
Date:   Tue May 17 20:32:10 2022 +0000

    FIX: typo of NCU

commit 6d13e9f8e8deab9f1724a63e6ce1845548207a75
Author: N0Ball <cwj0325@g.ncu.edu.tw>
Date:   Tue May 17 20:23:41 2022 +0000

    ADD: add NCU for demostrating how to commit.
    
    It's simply just a nonsense file with nonsense words; if it is for
    teaching it can be anything else. I suggest it to be a meme.

Too long?

git log --oneline

RESULT

9b605fe FIX: typo of NCU
6d13e9f ADD: add NCU for demostrating how to commit.

What if

You don't want the service down, but need the add modifications?
Or you have to cooperate with someone.

What if

You will never ever put an unworkable program on master

Let's add pretend we are another user.

git config user.name "jason"
git config user.email "jason@g.ncu.edu.tw"

SAVIOR - branches

SAVIOR - branches

OFTEN USED COMMAND

git branch jason
git branch dev

jason -> your branch name
dev -> short of develope

ALWAYS REMEMBER TO CHECK WHICH BRANCH YOU ARE ON

OFTEN USED COMMAND

git status

SAVIOR - branches

List all the branches you have (LOCAL)

OFTEN USED COMMAND

git branch

RESULT

  dev
  jason
* master

You can see that we have three branches.

SAVIOR - branches

Switch through branches

OFTEN USED COMMAND

git checkout jason

jason -> the target branch you want to switch to

Result

Switched to branch 'jason'

Remember to check if it is successed by status

Pretending someone

Make more changes!

echo "Nation Central University\!\!\!\!" >> NCU && echo "BAD" > AUTHOR # This appends "Nation Central University!!!!" to the file NCU and creates a file `AUTHOR` with content "BAD"

Append words to NCU is important for future usage.

Don't forget to commit it!

Pretending someone

OFTEN USED COMMAND

git status

Have U done it right?

Quick review

How to check your git movements?

REFLOG!

git reflog

RESULT

b50471b HEAD@{0}: commit: ADD: add comments to author
9b605fe HEAD@{1}: checkout: moving from master to jason
9b605fe HEAD@{2}: commit: FIX: typo of NCU
6d13e9f HEAD@{3}: commit (initial): ADD: add NCU for demostrating how to commit.

Practice

change back to your name and email
make changes in your dev branch.
make changes in your master branch.
change to another person again.
make changes in jason branch.
Repeat 1. once again.

NOTE

DO NOT change anything from old files.
you can check your config by

git config user.name
git config user.email

If you are correct

git log --graph --all

graph -> The graph view
all -> not only the current branch

What are these

network

Time to add (`merge`) them together!

What is merge?

Making two branches together.

How to merge?

you have to be on master branch!

OFTEN USED COMMAND

git merge jason

jason -> your targeted branch

Note

branch jason will not change, that's reasonable, since you can only modify what's on your current branch.

If you are correct

git log --graph --all

Wow Looks real cool

git merge dev

Let's merge dev and see what happens!

With some prettfier

*   N0Ball -> Merge branch 'dev'  (HEAD -> master)
|\  
| * N0Ball -> FIX: typo of filename  (dev)
| * N0Ball -> ADD: add readme file 
* |   N0Ball -> Merge branch 'jason' 
|\ \  
| * | jason -> FIX: modify author's comment to make it more readable  (jason)
| * | jason -> ADD: add comments to author 
| |/  
* | N0Ball -> ADD: add something more to make the graph better 
* | N0Ball -> ADD: add something to make the log graph looks cool 
|/  
* N0Ball -> FIX: typo of JASON 
* N0Ball -> ADD: add JASON for demostrating how to commit.

Try it yourself!

Merges are not always fluent

change to dev branch
modify NCU

remember that jason had append words to NCU
since it was merged to master -> NCU had appended words
both dev and master have its own appended words -> git doesn't know which to use -> CONFLICT

MERGE CONFLICTS

OFTEN USED COMMAND

git status

RESULT

On branch master
You have unmerged paths.
  (fix conflicts and run "git commit")
  (use "git merge --abort" to abort the merge)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
        both modified:   JASON

no changes added to commit (use "git add" and/or "git commit -a")

MERGE CONFLICTS

 FOREST SMELLS GOOD
<<<<<<< HEAD
National Central University!!!!
=======
Very long president duration
>>>>>>> dev

<<<<<< HEAD -> current status
>>>>>> dev -> incomming changes

You should choose. Keep both, leave one, delete both… whatever you like!

I chose to keep dev

MERGE CONFLICTS

fix conflicts
stage changes
commit changes
FINISH MERGE!

If everything works fine

*   N0Ball -> Merge branch 'dev' ( (HEAD -> master))
|\  
| * N0Ball -> ADD: add some words to JASON to make merge conflicts ( (dev))
* | N0Ball -> Merge branch 'dev' ()
|\| 
| * N0Ball -> FIX: typo of filename ()
| * N0Ball -> ADD: add readme file ()
* |   N0Ball -> Merge branch 'jason' ()
|\ \  
| * | jason -> FIX: modify author's comment to make it more readable ( (jason))
| * | jason -> ADD: add comments to author ()
| |/  
* | N0Ball -> ADD: add something more to make the graph better ()
* | N0Ball -> ADD: add something to make the log graph looks cool ()
|/  
* N0Ball -> FIX: typo of JASON ()
* N0Ball -> ADD: add JASON for demostrating how to commit. ()

GIT FLOW

How to git

IMPORTANT

You will never ever put an unworkable program on master.

you should not modify anything on master.
you should be very aware of merging to master.

WHO?

git blame AUTHOR

AUTHOR -> the target file to ask

Expected result

3add7ab5 (jason 2022-05-17 21:47:52 +0000 1) YOU ARE BAD

-L a, b can be used for lines

OOPS

I don't like this

Quick Reviews

STAGES of git

Quick Review

Working Directory
Staging Area
Repo

How to get to the wanted version?

I don't like

Working Directory

OFTEN USED COMMAND

git checkout .

same as add, . for everything or you can type the filename you want to restore

QUICK TEST

echo "OUO" > test

cat test # prints out the content inside test

git checkout test

cat test

I don't like

Staging Area

git restore --staged .

same as add, . for everything or you can type the filename you want to restore

QUICK TEST

echo "OUO" > test
git add .

git status

git restore --staged test

git status

I don't like

REPO

git reset

OPTIONS

--soft -> only changing status
--hard -> changes everything back to the commit status
- Just like git reset --soft + git checkout .

QUICK TEST SOFT

echo "wrong commit" > test
git add .
git commit -m "OOPS: wrong commit"

git log
cat test

echo "right commit" > test
git reset --soft xxxxx

xxxxx is the commit id

git log
cat test
git status

QUICK TEST HARD

echo "original commit" > test
git add .
git commit -m "OOPS: wrong commit"

git log && cat test

echo "new commit" > test
git reset --hard xxxxx

xxxxx is the commit id

git log && cat test
git status

I don't like

COMMIT

git commit --amend

QUICK TEST

echo "test" > test
git add .
git commit -m "ADD: discription of T3ST"

git log

git commit --amend -m "ADD: description for TEST"

git log

REMOTE

LET'S REMOTE

REGISTRATION

register a gitlab account!

GET REMOTE REPO

OFTEN USED COMMAND

git clone <repo url>

GITHUB

WHAT IS

At a high level, GitHub is a website and cloud-based service that helps developers store and manage their code, as well as track and control changes to their code. https://kinsta.com/application-hosting/

Clone methods

HTTPS: ask for username and password
SSH: use ssh key, which doesn't require username and password

Create a github

Lets create a repository

Go to Create a new repository

fill out the forms

You made it!

git

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changed 3 years ago 893 views