Git Tag Management and Best Practices

~~~~~~~~~~~~~~~~~~~~~~ If you are following somebody else's tree, you are most likely using remote-tracking branches (eg. `refs/remotes/origin/master`). You usually want the tags from the other end. On the other hand, if you are fetching because you would want a one-shot merge from somebody else, you typically do not want to get tags from there. This happens more often for people near the toplevel but not limited to them. Mere mortals when pulling from each other do not necessarily want to automatically get private anchor point tags from the other person. Often, "please pull" messages on the mailing list just provide two pieces of information: a repo URL and a branch name; this is designed to be easily cut&pasted at the end of a 'git fetch' command line: ------------ Linus, please pull from git://git..../proj.git master to get the following updates... ------------ becomes: ------------ $ git pull git://git..../proj.git master ------------ In such a case, you do not want to automatically follow the other person's tags. One important aspect of Git is its distributed nature, which largely means there is no inherent "upstream" or "downstream" in the system. On the face of it, the above example might seem to indicate that the tag namespace is owned by the upper echelon of people and that tags only flow downwards, but that is not the case. It only shows that the usage pattern determines who are interested in whose tags. A one-shot pull is a sign that a commit history is now crossing the boundary between one circle of people (e.g. "people who are primarily interested in the networking part of the kernel") who may have their own set of tags (e.g. "this is the third release candidate from the networking group to be proposed for general consumption with 2.6.21 release") to another circle of people (e.g. "people who integrate various subsystem improvements"). The latter are usually not interested in the detailed tags used internally in the former group (that is what "internal" means). That is why it is desirable not to follow tags automatically in this case. It may well be that among networking people, they may want to exchange the tags internal to their group, but in that workflow they are most likely tracking each other's progress by having remote-tracking branches. Again, the heuristic to automatically follow such tags is a good thing. On Backdating Tags ~~~~~~~~~~~~~~~~~~ If you have imported some changes from another VCS and would like to add tags for major releases of your work, it is useful to be able to specify the date to embed inside of the tag object; such data in the tag object affects, for example, the ordering of tags in the gitweb interface. To set the date used in future tag objects, set the environment variable GIT_COMMITTER_DATE (see the later discussion of possible values; the most common form is "YYYY-MM-DD HH:MM"). For example: ------------ $ GIT_COMMITTER_DATE="2006-10-02 10:31" git tag -s v1.0.1 ------------ include::date-formats.adoc[] FILES ----- `$GIT_DIR/TAG_EDITMSG`:: This file contains the message of an in-progress annotated tag. If `git tag` exits due to an error before creating an annotated tag then the tag message that has been provided by the user in an editor session will be available in this file, but may be overwritten by the next invocation of `git tag`. NOTES ----- include::ref-reachability-filters.adoc[] SEE ALSO -------- linkgit:git-check-ref-format[1]. linkgit:git-config[1]. GIT --- Part of the linkgit:git[1] suite

Properly managing tags in Git is crucial, especially when working with remote repositories and different groups of people, and understanding how tags are used and shared is essential to maintaining a organized and secure Git workflow, including considerations for one-shot pulls, tag namespaces, and backdating tags.