Bill LearWe have made a few changes to the post-receive hook for operation in our company. I wanted to pass them on in case they are suitable for more general use. Below I mix description of the change, a justification of the change, along with a snippet of code and/or code comments illustrating the change. I'm sure there are more sophisticated ways to do what we've done, but it seems to work for us.
1. Support per-branch mailing lists. This allows me to collaborate with several different people on different mini-projects from the same "hub" repository without each of them getting mail they don't care about.
Code:
# hooks.{branch}mailinglist
# This is the list that all pushes to a given branch will go to;
# leave it blank to not send emails for every ref update to this branch.
[...]
if [ -z "$recipients" ]; then
# Essentially an associative array,
# hooks.${short_refname}mailinglist: allows a separate mailing
# list for each branch/tag thingie.
recipients=$(git-repo-config hooks.${short_refname}mailinglist)
fi # One last try ...
if [ -z "$recipients" ]; then
recipients=$(git repo-config hooks.mailinglist)
fi # Check if we've got anyone to send to
if [ -z "$recipients" ]; then
echo >&2 "*** hooks.recipients is not set so no email will be sent"
echo >&2 "*** for $refname update $oldrev->$newrev"
exit 0
fi2. Allow specification of a prefix for the subject line. This allows us to better filter our email --- we use a mailing list for some projects and the mailing list prefixes the subject with its own string, for example.
Code:
# hooks.prefix # Set the email subject prefix to "[$hooks.prefix]". Defaults to empty string. [...] # Notes # ----- # All emails have their subjects prefixed with "[$hooks.prefix]" # to aid filtering, if hooks.prefix is set. If it is not set, no # prefix is used. [...] prefix=$(git-repo-config hooks.prefix)
if [ -n "$prefix" ]; then
EMAILPREFIX="[${prefix}] "
else
EMAILPREFIX=""
fi
[... elsewhere in the code]
generate_email_header()
{
# --- Email (all stdout will be the email)
# Generate header
cat <<-EOF
From: $committer
To: $recipients
Subject: ${EMAILPREFIX}$projectdesc $refname_type "$short_refname" ${change_type}d. $describe
X-Git-Refname: $refname
X-Git-Reftype: $refname_type
[...]3. Provide change content in email. The current hook does not produce
enough information for us --- we like to see the content of the change
so we can code-review on-the-fly. I hacked the code, in my ignorance,
to use git-whatchanged, as it seemed to provide what we wanted. I
am not currently controlling this behavior with a config flag, though
presumably it could be, easily.Code (simple diff): 408,411c399,400 < echo "Diffstat:" < git-diff-tree --no-color --stat -M -C --find-copies-harder $newrev ^$oldrev < echo "" < git-whatchanged --no-color -p --find-copies-harder $oldrev..$newrev ---
> echo "Summary of changes:" > git diff-tree --stat --summary --find-copies-harder $oldrev..$newrev
4 and 5.
4: Log the content of the emails, if desired, to a log file.
Our email archiving system here is between lame and nonexistent,
so we like to be able to look back at the logs if a problem should
occur. 5: Allow sending only a certain number of lines maximum to email
recipients. Some diffs are huge, so we don't want to overwhelm
recipients' inboxes. Note: currently, specifying the maximum number of email lines
only works when you specify logging, though this is not necessary.
Also: this might only be useful if you have a flag that controls
the use of git-whatchanged (or whatever) to produce a fuller diff
set in the email.Code:
# hooks.maxemaillines
# Clip the email sent out to this number of lines. If unset,
# defaults to 500 lines.
[...]
# hooks.logfile
# If set then the entire email content sent will be logged to this file.
# If unset, no logging is done.
[...]
maxemaillines=$(git-repo-config --int hooks.maxemaillines)
logfile=$(git-repo-config hooks.logfile)
[...]
# If a log file was specified, tee to the logfile, head, and then
# sendmail, else just send the mail directly.
if [ -n "$logfile" ]; then
while read oldrev newrev refname
do
generate_email $oldrev $newrev $refname |
/usr/bin/tee -a ${logfile} 2>/dev/null |
/usr/bin/head -${maxemaillines} |
/usr/sbin/sendmail -t $envelopesender
done
else
while read oldrev newrev refname
do
generate_email $oldrev $newrev $refname |
/usr/sbin/sendmail -t $envelopesender
done
fi6. Support an author filter. I don't have this running currently,
but I believe this feature was in the update script. Basically
(and here follows most likely confusion on my part) it allows you
to filter your changes out of a change set so that when you
push a change set that includes your changes to a hub, it only
sends them once (here, I'm most certainly not expressing this
correctly). Anyway, someone on the list suggested this, and it was in
the update hook, like this:authorfilter=$(git-repo-config hooks.authorfilter)
case "$refname_type" in
"tracking branch"|branch)
if expr "$oldrev" : '0*$' >/dev/null
then
# If the old reference is "0000..0000" then this is a new branch
# and so oldrev is not valid
echo " as a new $refname_type"
echo " to $newrev ($newrev_type)"
echo ""
# This shows all log entries that are not already covered by
# another ref - i.e. commits that are now accessible from this
# ref that were previously not accessible
git-whatchanged -p ${authorfilter:+--author="$authorfilter"} --pretty $newref $(git-rev-parse --not --all)
else
# oldrev is valid
oldrev_type=$(git-cat-file -t "$oldrev") # Now the problem is for cases like this:
# * --- * --- * --- * (oldrev)
# \
# * --- * --- * (newrev)
# i.e. there is no guarantee that newrev is a strict subset
# of oldrev - (would have required a force, but that's allowed).
# So, we can't simply say rev-list $oldrev..$newrev. Instead
# we find the common base of the two revs and list from there
baserev=$(git-merge-base $oldrev $newrev) # Commit with a parent
for rev in $(git-rev-list ${authorfilter:+--author="$authorfilter"} $newrev ^$baserev)
do
revtype=$(git-cat-file -t "$rev")
echo " via $rev ($revtype)"
done
if [ "$baserev" = "$oldrev" ]; then
echo " from $oldrev ($oldrev_type)"
else
echo " based on $baserev"
echo " from $oldrev ($oldrev_type)"
echo ""
echo "This ref update crossed a branch point; i.e. the old rev is not a strict subset"
echo "of the new rev. This occurs, when you --force push a change in a situation"
echo "like this:"
echo ""
echo " * -- * -- B -- O -- O -- O ($oldrev)"
echo " \\"
echo " N -- N -- N ($newrev)"
echo ""
echo "Therefore, we assume that you've already had alert emails for all of the O"
echo "revisions, and now give you all the revisions in the N branch from the common"
echo "base, B ($baserev), up to the new revision."
fi
echo ""
echo "Diffstat:"
git-diff-tree --no-color --stat -M -C --find-copies-harder $newrev ^$baserev
echo ""
git-whatchanged -p ${authorfilter:+--author="$authorfilter"} --pretty $newrev ^$baserev
fi
;;
"annotated tag")Ok, I think that's about it. Andy, let me know if I can help clarify anything.
Bill