How to retrieve the hash for the current commit in

Question

I would like to retain (for now) the ability to link Git changesets to workitems stored in TFS.

I already wrote a tool (using a hook from Git) in which I can inject workitemidentifiers into the message of a Git changeset.

However, I would also like to store the identifier of the Git commit (the hash) into a custom TFS workitem field. This way I can examine a workitem in TFS and see what Git changesets are associated with the workitem.

How can I easily retrieve the hash from the current commit from Git?

Answer 1

If you only want the shortened hash:

git log --pretty=format:'%h' -n 1

Further, using %H is another way to get the long hash.

Answer 2

There's always git describe as well. By default it gives you --

john@eleanor:/dev/shm/mpd/ncmpc/pkg (master)$ git describe --always
release-0.19-11-g7a68a75

Answer 3

For completeness, since no-one has suggested it yet. .git/refs/heads/master is a file that contains only one line: the hash of the latest commit on master. So you could just read it from there.

Or, as as command:

cat .git/refs/heads/master

---

Update:

Note that git now supports storing some head refs in the pack-ref file instead of as a file in the /refs/heads/ folder. https://www.kernel.org/pub/software/scm/git/docs/git-pack-refs.html

Answer 4

Commit hash

git show -s --format=%H

Abbreviated commit hash

git show -s --format=%h

Click here for more git show examples.

Answer 5

The most succinct way I know:

git show --pretty=%h 

If you want a specific number of digits of the hash you can add:

--abbrev=n

Answer 6

Here is another direct-access implementation:

head="$(cat ".git/HEAD")"
while [ "$head" != "${head#ref: }" ]; do
  head="$(cat ".git/${head#ref: }")"
done

This also works over http which is useful for local package archives (I know: for public web sites it's not recommended to make the .git directory accessable):

head="$(curl -s "$baseurl/.git/HEAD")"
while [ "$head" != "${head#ref: }" ]; do
  head="$(curl -s "$baseurl/.git/${head#ref: }")"
done