Chaining git hooks

Question

As many of you probably know, there can be only one hook type in git. If two update hooks need to be evaluated. The git admin is left with two unmanageable solutions:

1. Merge the hook scripts together
2. Manually chain them with an exec

I am looking for an elegant solution (written in BASH),something like a folder hooks/update.d or hooks/post-receive.d that will allow the loosely coupling of hook evaluations. The chaining should stop as soon as a hook fails.

I actually found an acceptable solution written in perl at this URL http://blog.bluefeet.net/2011/08/chained-git-hooks

The problem: my server runs different versions of perl and I am getting perllib version mismatches. It fails.

Answer 1

After further investigation and testing, here is a working solution:

create file .git/hooks/hook-chain as follows

#!/bin/bash # # author: orefalo  hookname=`basename $0`   FILE=`mktemp` trap 'rm -f $FILE' EXIT cat - > $FILE  for hook in $GIT_DIR/hooks/$hookname.* do     if test -x "$hook"; then #       echo $hook         cat $FILE | $hook "$@"         status=$?          if test $status -ne 0; then             echo Hook $hook failed with error code $status             exit $status         fi     fi done 

Now link any hook that requires chaining, for instance

• ln -s hook-chain update
• ln -s hook-chain post-receive

finally, create the chains by renaming them as hookname.action

 -rwxr-xr-x. 1 git  git  6710  functions  -rwxr-xr-x. 1 git  git   280  hook-chain  -rwxr-xr-x. 1 git  git  1524  post-mirror  lrwxrwxrwx. 1 root root   10  post-receive -> hook-chain  -rwxr-xr-x. 1 git  git  8763  post-receive.1email  -rwxr-xr-x. 1 git  git  1745  post-receive.2github  -rwxr-xr-x. 1 git  git   473  post-upload-pack  -rwxr-xr-x. 1 git  git   346  pre-receive  lrwxrwxrwx. 1 root root   10  update -> hook-chain  -rwxr-xr-x. 1 git  git  2975  update.1acl  -rwxr-xr-x. 1 git  git   328  update.2github 

for instance, in the sample above, the update hook will run update.1acl followed by update.2github.

The post-receive hook with run post-receive.1email followed by post-receive.2github

Answer 2

For those who're not willing to click on every link in comments below other answer, here's a practically unmodified version of the script by @HenrikN:

#!/bin/bash  # Runs all executable hookname-* hooks and exits after, # if any of them was not successful. # # Based on # http://osdir.com/ml/git/2009-01/msg00308.html  data=$(cat) exitcodes=() hookname=$(basename $0)  # Run each hook, passing through STDIN and storing the exit code. # We don't want to bail at the first failure, as the user might # then bypass the hooks without knowing about additional issues.  for hook in $GIT_DIR/hooks/$hookname-*; do   test -x "$hook" || continue   echo "$data" | "$hook"   exitcodes+=($?) done  # If any exit code isn't 0, bail.  for i in "${exitcodes[@]}"; do   [ "$i" == 0 ] || exit $i done