A3.5 Appendix C: Git Commands - Sharing and Updating Projects

The git fetch command communicates with a remote repository and fetches down all the information that is in that repository that is not in your current one and stores it in your local database.

We first look at this command in Fetching and Pulling from Your Remotes and we continue to see examples of it use in Remote Branches.

We also use it in several of the examples in Contributing to a Project.

We use it to fetch a single specific reference that is outside of the default space in Pull Request Refs and we see how to fetch from a bundle in Bundling.

We set up highly custom refspecs in order to make git fetch do something a little different than the default in The Refspec.

The git pull command is basically a combination of the git fetch and git merge commands, where Git will fetch from the remote you specify and then immediately try to merge it into the branch you’re on.

We introduce it quickly in Fetching and Pulling from Your Remotes and show how to see what it will merge if you run it in Inspecting a Remote.

We also see how to use it to help with rebasing difficulties in Rebase When You Rebase.

We show how to use it with a URL to pull in changes in a one-off fashion in Checking Out Remote Branches.

Finally, we very quickly mention that you can use the --verify-signatures option to it in order to verify that commits you are pulling have been GPG signed in Signing Commits.

The git push command is used to communicate with another repository, calculate what your local database has that the remote one does not, and then pushes the difference into the other repository. It requires write access to the other repository and so normally is authenticated somehow.

We first look at the git push command in Pushing to Your Remotes. Here we cover the basics of pushing a branch to a remote repository. In Pushing we go a little deeper into pushing specific branches and in Tracking Branches we see how to set up tracking branches to automatically push to. In Deleting Remote Branches we use the --delete flag to delete a branch on the server with git push.

Throughout Contributing to a Project we see several examples of using git push to share work on branches through multiple remotes.

We see how to use it to share tags that you have made with the --tags option in Sharing Tags.

In Publishing Submodule Changes we use the --recurse-submodules option to check that all of our submodules work has been published before pushing the superproject, which can be really helpful when using submodules.

In Other Client Hooks we talk briefly about the pre-push hook, which is a script we can setup to run before a push completes to verify that it should be allowed to push.

Finally, in Pushing Refspecs we look at pushing with a full refspec instead of the general shortcuts that are normally used. This can help you be very specific about what work you wish to share.

The git remote command is a management tool for your record of remote repositories. It allows you to save long URLs as short handles, such as “origin” so you don’t have to type them out all the time. You can have several of these and the git remote command is used to add, change and delete them.

This command is covered in detail in Working with Remotes, including listing, adding, removing and renaming them.

It is used in nearly every subsequent chapter in the book too, but always in the standard git remote add <name> <url> format.

The git archive command is used to create an archive file of a specific snapshot of the project.

We use git archive to create a tarball of a project for sharing in Preparing a Release.

The git submodule command is used to manage external repositories within a normal repositories. This could be for libraries or other types of shared resources. The submodule command has several sub-commands (add, update, sync, etc) for managing these resources.

This command is only mentioned and entirely covered in Submodules.