Git is a really powerful piece of version control software. Here is a short crash course on how to get started on it, I presented at the University of Portsmouth in April 2012.
What is version control?
Version control allows you to keep changes to files organised.
What makes Git so great?
- Git is really fast, mostly because it keeps a database on your local machine.
- Git is great for collaborative changes to files, so it's great for teams.
- Distributed. Git uses remotes, so I can push to a main repo or I can push to my mates a repo.
- Adds a .git folder in the root of the git folder as a database, so unlike SVN it will not add a .git folder to each folder in your tree.
- You can commit parts of a file to staging you have worked on for better peer review.
- Git doesn't delete anything, so it's almost impossible to lose stuff you've worked on.
Setting up Git (& SSH Keys)
GitHub have written a really good tutorial on setting up Git on your OS. For the most part, just you need to run through the installer using the default options.
Cloning a Repo
Cloning a repo will copy it's files & history to your machine. Most git repos will provide you with a URL like 'firstname.lastname@example.org:MikeRogers0/siteng.in—SiteEngines-Site.git'. The 'foldername' is the directory you wish to clone to.
git clone URL foldername
Reviewing & Staging Changes
Once you have some some edits, you can stage them (Add them into version control with a brief message about what you have done).
# Add all the new files in the repo into the next commit. git add . git commit -m 'Message Here'
git commit -a -m 'Message here'
Branches are really powerful, they allow you to work on features independent from other peoples work. So for example, you could have someone adding a new feature to a site while the CSS is being edited in another branch & you will not overwrite each others work. When your happy that the feature is done you can than merge is back into your master brach & deploy it.
Review the branches available
git checkout branchname
Make a new branch
git checkout -b branchname
Git is really good at looking at changes in different versions of a file & merging them together as to not cause errors.
git checkout master; git merge branchname;
Pushing a branch updates a remote repo.
Pulling changes will fetch what others have pushed to a repo & merge them into your local git repo.
git fetch; git merge origin/branchname