git Usage (1)

Create a Working Directory & a Local Repository

testuser@mac3:~$

testuser@mac3:~/testrepo$

Leeres Git-Repository in /home/testuser/testrepo/.git/ initialisiert

git Usage (2)

Create an ASCII¹ File (1)

git Usage (3)

Create an ASCII File (2)

Type the following into the text editor

This is the first file of my project
Version: 1

and save the file as my_firstfile.txt in the Working Directory you just created for your project (~/testrepo); close the editor

git Usage (4)

Project Status

In the Terminal type:

git status

Auf Branch main

Noch keine Commits

Unversionierte Dateien:
  (benutzen Sie "git add <Datei>...", um die Änderungen zum Commit vorzumerken)
    my_firstfile.txt

nichts zum Commit vorgemerkt, aber es gibt unversionierte Dateien
(benutzen Sie "git add" zum Versionieren)

git Usage (5)

Add File to Index

In the Terminal, type:

git add my_firstfile.txt

git Usage (6)

Commit Staged File(s) to Repository

To commit all files in the Staging Area to the Repository, type:

git commit -m "Initial commit"

gitGraph
   commit id: "Initial commit"

git Usage (7)

Edit a File

gitGraph
   commit id: "Initial commit"

• Re-open testrepo/my_firstfile.txt
• Change Version: 1 to read Version: 2
• Save, and exit editor
• git status
• git add my_firstfile.txt
• git commit -m "Bump version _in file_"

gitGraph
   commit id: "Initial commit"
   commit id: "Bump version"

• Use git status and git show to investigate repo

git Usage (8)

Intermediate Overview

---
config:
  look: handDrawn
---
flowchart LR
    mkdir["Create Working Directory<br>mkdir ~/testrepo"] --> cd["Change into Working Directory<br>cd ~/testrepo"]
    cd --> gitinit["Create Local Repository<br>git init"]
    gitinit --> nano["Create/change file<br>nano my_firstfile.txt"]
    nano --> gitadd["Add to Staging Area (Index)<br>git add my_firstfile.txt"]
    gitadd --> nano
    gitadd --> gitcommit["Commit staged changes to Local Repository<br>git commit -m 'Initial commit'"]
    gitcommit --> nano

block-beta
    columns 2
        block
            columns 3
            local["Local Repository"]:3            
            wdt["Working Directory"] idxt["Staging Index"] lrt["Commit History"]
            space:2 gitclonedotId1((" "))
            gitaddId((" ")) -- "git add" --> gitadddotId((" ")) space
            space:3
            space gitadddotId --> gitcommitId((" ")) 
            gitcommitId -- "git commit" --> gitcommitdotId((" "))
            style local stroke-width:0px,fill:#fefbe0;
            style gitaddId stroke-width:0px,fill:#fefbe0;
            style gitcommitId stroke-width:0px,fill:#fefbe0;
            style gitcommitdotId stroke-width:0px,fill:#fefbe0;
            style gitadddotId stroke-width:0px,fill:#fefbe0;
            style gitclonedotId1 stroke-width:0px,fill:#fefbe0;
        end

Setup GitLab (1)

• Point your browser to
  • https://gitlab.gwdg.de/, or to
  • https://gitlab.com/users/sign_in
    
• Either set up a profile, or log in
• On the GitLab page, click on your avatar -> SSH Keys -> Add new key
• Paste the output of
  cat ~/.ssh/id_rsa.pub
  into the Key field on the GitLab page

Setup GitLab (2)

• Test connection:
  Either
  ssh -T git@gitlab.gwdg.de
  or
  ssh -T git@gitlab.com

git Usage (9)

‘Mirror’ a Local Repository Remotely

gitGraph
   commit id: "Initial commit"
   commit id: "Bump version"

• In the Terminal, type
  git remote add origin git@gitlab.gwdg.de:<your-gitlab-handle>/testrepo.git¹
• git push --set-upstream origin main

git Usage (10)

Pull/Push Remote (Collaborate!) (1)

gitGraph
   commit id: "Initial commit"
   commit id: "Bump version"

• git pull (fetches & merges remote w/ local current branch)
• Obtain the hash of commit ‘Bump version[…]’ from
  git show
• git checkout -b test <commit-hash> (create new branch test from commit)

gitGraph
   commit id: "Initial commit"
   commit id: "Bump version"
   branch test

• git status

git Usage (11)

Pull/Push Remote (Collaborate!) (2)

gitGraph
   commit id: "Initial commit"
   commit id: "Bump version"
   branch test

• Add this line
  Edited file in branch test
  to the file my_firstfile.txt (change file contents in branch test)
• git add my_firstfile.txt (add changes to index of branch test)
• git commit -m "Edit file" (commit to branch test)

gitGraph
   commit id: "Initial commit"
   commit id: "Bump version"
   branch test
   checkout test
   commit id: "Edit file"

git Usage (12)

Pull/Push Remote (Collaborate!) (3)

gitGraph
   commit id: "Initial commit"
   commit id: "Bump version"
   branch test
   checkout test
   commit id: "Edit file"

• Optional:
  git push origin test (provide new remote branch name)
• git checkout main (return to main branch)
• Open my_firstfile.txt—which version do you see?
• git pull (sync with remote main branch)

git Usage (13)

Pull/Push Remote (Collaborate!) (4)

Merge a Branch with main

gitGraph
   commit id: "Initial commit"
   commit id: "Bump version"
   branch test
   checkout test
   commit id: "Edit file"

• git merge test (merge everything in branch test w/ branch main—implies a commit)

gitGraph
   commit id: "Initial commit"
   commit id: "Bump version"
   branch test
   checkout test
   commit id: "Edit file"
   checkout main
   merge test tag: "First merge"

• Check the contents of my_firstfile.txt!
• git push (push everything online, i.e. publish)

End of Part 2

Thank you for your attention!