DevOps Tools/SCM/Git
Overview | Continuous Integration (CI) | Source Control Management (SCM) | Containerization | Configuration | Integration
Contents |
Git
Install and Configure
Done on CentOS 7. Serves as an agentless server and client. You can use this package to create a local repository as well as other git functions.
~$ yum install git
Setup global parameters
~$ sudo git config --global user.name "global username" ~$ sudo git config --global user.email "email address" ~$ sudo git config --system core.editor "/bin/vim"
Configuration Files
At the time of this writing, Git has (4) potential places for configuration files:
System
Having the most weight, this is located in the main directory. It applies to the entire system.
$(prefix)/etc/gitconfig
Global
With the second heaviest weight, this file does not exist by default. It is user specific.
~/.gitconfig
Custom
Another file that does not exist by default it lives in one of (2) places. It is also user specific.
$XDG_CONFIG_HOME/.config/git/config $HOME/.config/git/config
Repository (Local)
And last the repository specific config file, sometimes referred to as local.
$GIT_DIR/config
Initializing Local Repo
Create a local directory with nothing in it. This is called initializing the repository
~$ mkdir ~/repo ~$ git init ~/repo Initialized empty Git repository in /home/user/repo/.git/
Set repo user & email, if you want something different from the global.
~$ git config user.name "user" ~$ git config user.email "[email protected]"
git clone
You can also initialize a directory by simply doing a git clone of the repo. Without a specified directory, a new folder will be created based on the name of the repository.
~$ git clone [email protected]:infrastructure/ansible.git
multiple repos/ssh keys
Personally, I found the simplest way to deal with multiple repos that need different ssh keys is to utilize a parent .gitconfig that lives in the user home directory along with individual .gitconfig files that live in the parent folder of each project (not the repository folder).
for example:
home/.gitconfig home/git/project-1/.gitconfig home/git/project-2/.gitconfig
home .gitconfig
~$cat $HOME/.gitconfig # project-1 user [includeIf "gitdir:~/git/project-1/"] path = ~/git/project-1/.gitconfig # project-2 user [includeIf "gitdir:~/git/project-2/"] path = ~/git/project-2/.gitconfig
parent .gitconfig
~$ cat $HOME/git/project-1/.gitconfig [user] name = My Project-1 Account Name email = [email protected] [core] sshCommand = "ssh -i ~/.ssh/project-1_id_rsa"
Basics
add
adds a new file to the repo.
~$ git add filename ~$ git add * ---- adds everything in the current directory ~$ git add . ---- adds everything in the current directory
status
shows the current status of the git repository
~$ git status
commit
Commits the changes to the repo
~$ git commit -m "comment on commit"
commit anything that is staged, but not anything that is untracked.
~$ git commit -a
delete
deletes a file from the git repo. you must delete the file first.
~$ rm filename ~$ git rm filename
log
Shows you a log of all the commits and changes.
~$ git log ~$ git log --oneline ----- shows the logs in a single line ~$ git log -p ----- shows details of the changes per line per log. ~$ git log --author="username" ------- shows logs of a certain user ~$ git log --grep="search term" ------- shows logs of changes that match the search term ~$ git log --graph --decorate ------ shows a directory tree view of the changes.
clone
Clones a git repository
~$ git clone "local path" ~$ git clone user@hostname:repo_directory --- assumes the repo directory is in the remote user's home directory. ~$ git clone https://github.com/repository/project.git ~$ git clone https://[email protected]/username/repository.git
push
push changes to repo
~$ git push origin master
pull
pull changes from repo to local
~$ git pull origin master
pull changes from a feature branch
~$ git pull origin feature/branch_name
ignore
Ignore file types in local/specific repository
~$ vim .gitignore #local git ignore in specific repo *.filetype /ignored_directory/*
merge
merges two branches together. start by selecting the branch you want to merge another branch into.
~$ git merge branch_name
rm
remove a file from the repo and local
~$ git rm {file name}
reset
reset any adds
git reset
reset the local branch and remove any local commits
git reset --hard origin/master
Global Settings
exclude
Show excluded files
~$ git config --global core.excludesfile
Exclude file/path
~$ git config --global core.excludesfile '/etc/gitignore'
Manually ignore files via exclude file
~$ sudo vim /etc/gitignore # globally ignore files based on type *.filetype
Branch
Determine current branch
~$ git branch
Create new branch
~$ git branch new_branch
Select new branch
~$ git checkout branch_name
Create new branch and select at the same time
~$ git checkout -b new_branch
List all branches
~$ git branch -a
Examples
Clone new project and push initial commit
Assuming you've created the project in GitLab already. This is also using a non-standard port.
~$ git clone ssh://[email protected]:8922/user/project01.git ~$ cd ./project01 ~$ touch README.md ~$ git add ./README.md ~$ git commit -m "initial commit" ~$ git push ssh://[email protected]:8922/user/project01.git master
Create a new branch for changes, then merge into master
~$ git pull origin master ~$ git status On branch master ~$ git checkout -b new_feature_01 #create a new branch and switch to it Switched to a new branch 'new_feature_01' ~$ git status On branch new_feature_01 ~$ vim ./index.html #new changes ~$ git add . #add new files ~$ git commit -m "html index" #commit changes ~$ git push ssh://[email protected]:8922/user/project01.git new_feature_01 #push changes to branch ~$ git checkout master #switch back to master branch ~$ git pull origin master #pull master branch down (overwrites local changes committed to new branch) ~$ git merge new_feature_01 #merge new branch into master ~$ git push origin master #commit changes to master ~$ git branch -d new_feature_01 #delete new branch (local) ~$ git push origin --delete new_feature_01 #delete new branch (remote)
Update existing branch
~$ git checkout branch01 ~$ git add . ~$ git commit -m "new commit message" ~$ git push origin branch01
