Git, rewriting history of master branch and associated tags

Question

I've just had my first experience with rewriting the history of one of my repos (using git-filter-branch). The problem is that the repo had several tags, which after rewriting seem to be completely disconnected from the resulted history. I think this is due to the fact that the history associated with the tags hasn't been rewritten, so they have to point to the old commits. So, what can I do to "apply" the tags on the new history. A little ASCII art, maybe it's easier to understand my question:

Original repo:

+  HEAD
|
|
+  TAG 0.2.0
|
|
+  TAG 0.1.0
|
|
+  Initial commit

Repo structure reported by gitk --all after history rewrite:

    +  HEAD
    |
    |
    |
    |
    |
    |
    |
    |
    +  Initial commit
+  HEAD
|
|
+  TAG 0.2.0
|
|
+  TAG 0.1.0
|
|
+  Initial commit

Answer 1

Look like the last step of this procedure described here

$ git log --pretty=oneline origin/releases |
  sed -n -e '/^\([0-9a-f]\{40\}\) Tag\( release\)\? \(.*\)/s--\3|\1|Tag release \3-p'
  > ~/paludis-git-tags

$ while read name msg head ; do
  git tag -m "${msg}" ${name} ${head} ;
  done < paludis-git-tags

The idea is to read tags from the old versions of the repositories, to re-apply them on the new history.

---

Note: in your original use of git-filter-branch, did you use the:

-- --all

?

the -- that separates filter-branch options from revision options, and the --all to rewrite all branches and tags.

It may have kept the tag in place on the new history (I have not tested it yet though)

Answer 2

First, you have to rewrite tags too, e.g. (as VonC said) by using --all option to rewrite all references.

If you have annotated tags (heavyweight tags) you have also to use --tag-name-filter option, e.g. as --tag-name-filter cat. Note that you cannot rewrite signed tags!