1. Github Tutorial Kan Qi kqi@usc.edu

2. The Big Picture

3. Local environment workspace Index
The directory in your file system where you hold your project source code.
git init
git clone <repo-url>
Index
containing a sorted list of file paths.
git ls-files --stage
git add
git rm

4. Local environment - cont’d
Local repository
.git directory in your workspace directory
Hold branches and commits for each branch.
HEAD refers to the currently checked out commit.
git commit [-m]
git pull <remote> <branch>
git checkout <branch>
git push <remote> <branch>
git fetch
git revert <commit-ish>

5. Remote repository
Remote repository is a repository hosted somewhere on Internet or local network.
Commands available to manage remote repositories
git remote [-v | --verbose]
git remote add <name> <url>
git remote remove <name>
git remote set-url <name> <newurl>
Four transfer protocols
http
local
git
SSH
To be able to collaborate on any Git project, you need to know how to manage your remote repositories. Remote repositories are versions of your project that are hosted on the Internet or network somewhere. You can have several of them, each of which generally is either read-only or read/write for you. Collaborating with others involves managing these remote repositories and pushing and pulling data to and from them when you need to share work. Managing remote repositories includes knowing how to add remote repositories, remove remotes that are no longer valid, manage various remote branches and define them as being tracked or not, and more. In this section, we’ll cover some of these remote-management skills.

6. Collaboration - Typical workflow
Person A
Setup project & repo
push code onto github
edit/commit
pull/push
Person B
clone code from github
edit/commit/push
edit…
edit… commit
pull/push

7. Collaborating - clone
git clone name>/<repository name>.git
git clone

8. Collaborating - fetch, pull
Options for synchronizing:
Fetch
Fetch all the branches to local repository to be able to access the remote branches.
git fetch <remote>
Pull
Pull the changes in remote branch and apply those changes directly to the workspace.
Usually we need to solve conflicts after we pull.
git pull <remote> <branch>

9. Collaborating - merge,push
Merge the current working branch with another branch.
git merge <branch>
Push
Push the commit you make in local repository to remote repository
git push <remote> <branch>

10. Demo - Collaboration
User1 and user2 both clone the same project from github
git clone
User1 make some changes and commit to the remote master branch.
git commit -m “edit readme file for greeting”
git push origin master
User2 is also doing some changes in local and commit to local repository.
When user2 pushes the local commit, it conflicts with the remote master branch.
User2 pulls the commit from remote and solve the conflicts.
git pull
User2 commits and pushes again.
git commit -m “solve the conflict about the readme file”

11. Demo - Collaboration - cont’d
User2 creates a branch named “maintain_branch” in local.
git checkout -b “maintain_branch”
User2 makes changes and commit into “maintain_branch”
git add --all & git commit -m “added maintain branch”
User2 pushes the branch into remote repository
git push –-set-upstream origin maintain_branch
User1 fetches the branch from the remote repository and merge the two branches by solving the conflicts.
git fetch
git merge maintain_branch
User1 pushes the master branch with the changes from maintain branch back to remote repository
git push origin master

12. 577a course project requirements
Every team should host their project on github in private repository
Register a student account, and you get up to 5 private repository quota
Add TAs as collaborators.
Commit message format
Git commit -m “your comment”
E.g git commit -m “added username format check function”