Githandson

Git Hands-on

All of these exercises should be followed on naf-school03 using your school account

Note that lines beginning with a $ sign implies a shell command!

Exercise 1 (Configuration)

• $ mkdir -p ~/school/git
• $ cd ~/school/git
• Configure git
  • $ git config --global user.name "Your Name"
  • $ git config --global user.email you.email@domain

• $ cat ~/.gitconfig

• optional extras for config (and obviously editor is mutually exclusive)
  • $ git config --global color.ui auto # If you like colours!
  • $ git config --global alias.co checkout
  • $ git config --global alias.st status
  • $ git config --global alias.ci commit
  • $ git config --global core.editor emacs # flame bait
  • $ git config --global core.editor vim

Exercise 2 (Basics)

Let's commit some stuff to git...

• $ git init
• $ git status
• $ touch readme.txt
• $ echo "hello" > readme.txt
• $ git commit
• $ git add .
• $ git commit
• $ git "bye" >> readme.txt
• $ git status
• $ git reset

Exercise 3 (Working with remote repository)

• $ git clone gridkapuppet01:/opt/repo.git
• $ git log

Add a new file to local repository and submit the changes to remote

• $ git clone git@naf-school04:gitlab
• $ cd gitlab
• $ git status
• $ vi ${USER}.txt
  • write something
• $ git status # what is updated? Working tree, Index or Repository?
  • $ git diff
  • $ git diff HEAD
  • $ git diff --cached
• $ git add ${USER}.txt
  • $ git status
  • $ git diff
  • $ git diff HEAD
  • $ git diff --cached
• $ git commit -m "Add user text file"
  • $ git status
  • $ git diff
  • $ git diff HEAD
  • $ git diff --cached
• $ git push origin master
  • this might not work! Why?
  • tip: what does “git pull --rebase” do?
• $ git checkout -b ${USER} master # specifying "master" here is just a good habit. Always beware of defaults.
• $ vi config.yaml
  • Add a user to the list
• $ git add -p
• $ git commit -m "Adding ${USER} to users list"
• $ git push origin ${USER}
• $ git checkout master
• $ git merge ${USER}
• $ git push origin master
  • What happens?
• $ git checkout -b newfeature_${USER} master
• $ vi config.yaml
  • add a server
  • commit the change (with a good message!)
  • $ git log
• Oops! We mistyped the server, vi config.yaml again
  • change the name of the server
  • commit the change
  • $ git rebase -i HEAD~2
  • use “fixup” or “squash” on the fix (make sure you understand the difference)
  • $ git log # examine the differences

Git cheat sheet

Git configuration

• Git levels:

/etc/gitconfig - global git config for any user

~/.gitconfig -user specific

~/repo/.git/config -repo specific

each level ovewrites prevous.

git config --global user.name "Your Name"

git config --global user.email you.email@domain

git config --global color.ui auto # If you like colours!

git config --global alias.co checkout

git config --global alias.st status

git config --global alias.ci commit

git config --global core.editor emacs

Git basics

git init                        - create new local repo 
git clone /path/to/repository   - check out a repository
git clone https://github.com/   - clone repo from github 
git add <filename>              - add specified file to staging area 
git add .                       - add all subdirectories and files recursivly
git reset                       - removes all added files from staging area, keeps the changes 
git reset --hard                - removes all added files from staging area, drops the local changes after last commit

git status                      - List the files you've changed and those you still need to add
git help                        - Help for most commonly used git commands
git help <command>              - Detailed help for specified command

git init --bare --shared        - Creates empty repository meaning no working directory in it. 
git remote add origin REMOTEURL - git remote add creates an entry in your git config that specifies a name of a particular URL of the remote 
git remote rm origin            - removes added remote repository
                                  git repo. This command can be used only after creation of local repo with git init or git clone. 
git clone                       - creates a new git repository by copying an existing one located at the URI you specify.