20. Working with tags

20. Working with Tags in GIT and GitHub

Tags are an essential feature in the world of code versioning with GIT, offering a powerful way to mark specific points in a repository's history as important. Generally, they are used to mark releases of software, allowing developers and end users to easily find and download a stable version of the code. In this chapter, we'll explore how to work with tags in GIT and how they can be synced with GitHub.

Creating Tags

Creating a tag in GIT is a simple process. A tag can be lightweight or annotated. Soft tags are like pointers to a specific commit - similar to a branch that doesn't change - while annotated tags are stored as full objects in the GIT database. They can contain the tag author's name, email, date and an associated message, similar to a commit.

            
                # Creating an annotated tag
                git tag -a v1.0 -m "Version 1.0 released"

                # Creating a lightweight tag
                git tag v1.0-lw
            
        

List Tags

To see all existing tags in a repository, you can use the git tag command. This command will list all tags in alphabetical order; The -l or --list option can be used to list tags that meet a specific standard.

            
                # Listing all tags
                git tag

                # Listing tags that meet a standard
                git tag -l "v1.*"
            
        

Checking Tag Information

To check the information for an annotated tag, you can use the git show command followed by the tag name. This will show the tag's message, author, date, and changes to the commit the tag is pointing to.

            
                # Checking information from an annotated tag
                git show v1.0
            
        

Tag Checkout

You can checkout a tag to view the state of the code at that specific point in time. This is useful for compiling and testing previous versions of a project. However, when you checkout a tag, you will be in a detached 'HEAD', which means that any new commits you create will not be in any branch and may be difficult to find later.

            
                # Checking out a tag
                git checkout v1.0
            
        

Deleting Tags

If you need to remove a tag for any reason, you can do so with the git tag -d command. This will remove the tag from the local repository but not from the remote repository.

            
                # Deleting a tag locally
                git tag -d v1.0
            
        

Publishing Tags

After you create a tag locally, you may want to share it with other developers or publish it to GitHub. To do this, you must "push" the tag to the remote repository.

            
                # Publishing a specific tag
                git push origin v1.0

                # Publishing all tags that are not already on the remote
                git push origin --tags
            
        

Removing Tags from the Remote Repository

To remove a tag from the remote repository, you must use the git push command with the --delete option followed by the tag name.

            
                # Removing a tag from the remote repository
                git push --delete origin v1.0
            
        

Conclusion

Tags are an extremely useful tool in GIT and GitHub for marking software version releases. They allow you and other developers to easily access specific versions of the code. Whether creating, listing, verifying, checking out, deleting or publishing tags, version control becomes more organized and accessible. With practice, using tags will become a natural part of your software development workflow.