Git shouldn't be scary, but it can be when you are first starting to use it. Here's a quick GIT guide you can use as a reference or cheat sheet. I am always forgetting so this may be for my own benefit.
git config --global color.ui true git config --global user.name "YOUR NAME" git config --global user.email "YOUR@EMAIL.com" # Optional: git config format.pretty oneline # Set your default git editor git config --global core.editor vim # Generate your SSH Key ssh-keygen -t rsa -b 4096 -C "YOUR@EMAIL.com" # Display and copy your new SSH key cat ~/.ssh/id_rsa.pub # Add it to your Github account by visiting: https://github.com/settings/keys # Check that it worked by running ssh -T email@example.com # You should see this: Hi Name!, # You've successfully authenticated, but GitHub does not provide shell access. # View your configuration settings git config --list
git help man git
Creating A New Repository
# Initialize a local git repository with git init # If git init does not work, make sure you have a .git folder. mkdir .git
Clone An Existing Repository
# clone a repository with SSH git clone firstname.lastname@example.org:username/application-name.git # clone with https (better to use SSH) git clone: https://github.com/username/application-name.git # Add a remote origin to your existing application git remote add origin <remote_url> # View the remote with git remote -v # View information about your remote git remote show origin # Rename your remote git remote rename mirrorcommunications mirrorcomm
Committing & Inspecting Local Changes
# Review file changes before staging them with git diff # See the files you have staged with git diff --staged # Add files to the staging area with git add <filename> # Add multiple files for staging with git add <filename> <filename> # For an interactive view of your file changes, run git add -p <filename> # Add all files to staging with git add . # Commit staged changes with git commit -m 'commit message' # Create tags (for software development) for your commits git tag 1.0.0 1b2e1d63ff # List your tags git tag # List all tags for a specific segment (all tags that end in 1.86) git tag -l "v1.86*" # View a specific tag git show v.1.0.0 # Delete a tag git tag -d v1.0.0 # Delete a tag from a remote server git push origin --delete <tagname> # Show your file changes that have not been committed yet with git status
Git Log Commands
# Show your last 5 commits with git log # Show a specified number of commits with git log -3 # Show all commits with git log --all # Filter commits by author, with git log --author=Brian # Filter commits by committer with git log --committer=Brian # View commits by date range git log --before or --after <date> # Examples: git log --after 2.days.ago | git log --after "2019-01-05" --before "2016-01-05" # To view the changes for each commit found, run git log -p git log -p 2 # last two commits # To view a summary of the changes made in each commit run git log --stat # View one line of information per commit git log --oneline # View one line of information per commit and make it look pretty git log --pretty=oneline # Find more options with git help log
Creating & Merging New Branches
# Create a new branch with git branch <new-branch-name> # Move into the new branch with git checkout <new-branch-name> # Create a new branch and switch into it automatically git checkout -b <new-branch-name> # List all of your branches with git branch # Merge a branch into master git checkout master git merge <branch-name> # Delete a branch git branch -d <branch-name> # View the last commit of all your branches git branch -v # View branches you have merged git branch --merged # View branches you haven't merged git branch --no-merged
# NOTE: Never use rebase on public branches # Rebasing allows you to incorporate changes from your master branch into a feature branch git checkout some-feature git rebase master # This moves the entire feature branch to begin at the top of the master branch # Interactive Rebasing # Allows you to review all the commits that are about to be moved git checkout some-feature git rebase -i master # Only move the last three commits example git rebase -i HEAD~3 # After running the above command you can use: # p, pick = use commit # r, reword = use commit, but edit the commit message # e, edit = use commit, but stop for amending # s, squash = use commit, but meld into the previous commit # f, fixup = like "squash", but discard this commit's log message # x, exec = run command (the rest of the line) using shell
Push, Pull & Fetch
# Push your code to a remote repository with git push origin master git push heroku master etc. # Forcing a push with -f git push -f <location> # Specify a remote branch to push git push <location> <branch-name> # Pull changes from a remote or server with git pull <location> # Pull changes from a remote or server branch with git checkout --track <location> <branch-name> # Download and inspect changes from a remote server without committing them git fetch <location>
# Revert back to a working commit with (Be Careful with this!) git reset --hard <commit-string> Other options include --soft and --mixed # Unstage a file, but keep your changes git reset HEAD <filename> # Reset two commits git reset HEAD~2 # Discard changes in a file (Be Careful with this!) git checkout --<filename> # Drop your local changes and use the server instead git fetch origin git reset --hard origin/master # Revert to the second last commit with git revert HEAD^ # Revert a commit with a specified id git revert c7861gf # Modify your last commit message with git commit --amend -m "New Commit Message" # Add a file to a previous commit git add somefile git commit --amend --no-edit # Remove a staged file for a commit (Maybe a file you don't want tracked!) git rm --cached <filename> echo <filename> >> .gitignore # For merge conflicts, run git status # Discard local file modifications with: git checkout --<filename> or <folder> <folder2>
You can also set up aliases for git commands. I prefer to do this in my ~/.bash_aliases file, but the approach below is also a great option.
git config --global alias.ga git add . git config --global alias.ci commit git config --global alias.st status
The Cherry Pick command lets you add commits to the current working HEAD. Basically, you are picking a commit from another branch and applying it to a new branch or master.
# First find the commit you want to cherry pick git log --oneline # Now, copy the commit string # Switch into the branch where you want to put the cherry-picked commit git checkout new-feature # Now add it with git cherry-pick <commit-string>
Working with Forks
If you want to experiment with an existing repository, you can fork it and create changes without affecting the original project. To do this, view an existing repository on Github and hit the Fork button.
# Now git clone your Fork git clone email@example.com:username/repo-name.git cd repo-name $ git remote -v # This will list your current configured remote repository for your fork # Example: > origin https://github.com/username/your_fork.git (fetch) > origin https://github.com/username/your_fork.git (push) # Now add the original repository to sync with your fork git remote add upstream firstname.lastname@example.org/original_owner/original_repository.git # Verify it worked by running $ git remote -v # Fetch changes from the remote repository with git fetch remote-name # Pull and merge changes from a remote repository git pull remote-name branch-name # Grabs online updates and merges them with your local work # If you want your changes to be added to the original repo git push origin master # Now visit your Fork on Github # Next create a pull request