update-hook: Major overhaul (handling tags, mainly).

This is the update hook we use in all our git-repos.

It has some improvements over the original version, namely:
* Don't send every commit since dawn of time when adding a new tag.
* When updating an annotated tag, just send the diffs since the last tag.
* Add diffstat output for 'normal' commits (top) and annotated tags (bottom).
* Block un-annotated tags in shared repos.

I'm a bit uncertain about that last one, but it demonstrates how to
disallow updates of a ref which we use, so I kept it.

Note that git-describe is needed for the "changes since last annotated tag"
thing to work.

Signed-off-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/templates/hooks--update b/templates/hooks--update
index 6db555f6580ca0831cf285a62ab7354211168203..27cea174d135eb82f9e0229a0adf4f4993c60f2d 100644 (file)
--- a/templates/hooks--update
+++ b/templates/hooks--update
@@ -1,6 +1,7 @@
 #!/bin/sh
 #
 # An example hook script to mail out commit update information.
+# It also blocks tags that aren't annotated.
 # Called by git-receive-pack with arguments: refname sha1-old sha1-new
 #
 # To enable this hook:
@@ -8,16 +9,74 @@
 # (2) make this file executable by "chmod +x update".
 #
 
-recipient="commit-list@example.com"
+project=$(cat $GIT_DIR/description)
+recipients="commit-list@somewhere.com commit-list@somewhereelse.com"
 
-if expr "$2" : '0*$' >/dev/null
+ref_type=$(git cat-file -t "$3")
+
+# Only allow annotated tags in a shared repo
+# Remove this code to treat dumb tags the same as everything else
+case "$1","$ref_type" in
+refs/tags/*,commit)
+       echo "*** Un-annotated tags are not allowed in this repo" >&2
+       echo "*** Use 'git tag [ -a | -s ]' for tags you want to propagate."
+       exit 1;;
+refs/tags/*,tag)
+       echo "### Pushing version '${1##refs/tags/}' to the masses" >&2
+       # recipients="release-announce@somwehere.com announce@somewhereelse.com"
+       ;;
+esac
+
+# set this  to 'cat' to get a very detailed listing.
+# short only kicks in when an annotated tag is added
+short='git shortlog'
+
+# see 'date --help' for info on how to write this
+# The default is a human-readable iso8601-like format with minute
+# precision ('2006-01-25 15:58 +0100' for example)
+date_format="%F %R %z"
+
+(if expr "$2" : '0*$' >/dev/null
 then
-       echo "Created a new ref, with the following commits:"
-       git-rev-list --pretty "$3"
+       # new ref
+       case "$1" in
+       refs/tags/*)
+               # a pushed and annotated tag (usually) means a new version
+               tag="${1##refs/tags/}"
+               if [ "$ref_type" = tag ]; then
+                       eval $(git cat-file tag $3 | \
+                               sed -n '4s/tagger \([^>]*>\)[^0-9]*\([0-9]*\).*/tagger="\1" ts="\2"/p')
+                       date=$(date --date="1970-01-01 00:00:00 $ts seconds" +"$date_format")
+                       echo "Tag '$tag' created by $tagger at $date"
+                       git cat-file tag $3 | sed -n '5,$p'
+                       echo
+               fi
+               prev=$(git describe "$3^" | sed 's/-g.*//')
+               # the first tag in a repo will yield no $prev
+               if [ -z "$prev" ]; then
+                       echo "Changes since the dawn of time:"
+                       git rev-list --pretty $3 | $short
+               else
+                       echo "Changes since $prev:"
+                       git rev-list --pretty $prev..$3 | $short
+                       echo ---
+                       git diff $prev..$3 | diffstat -p1
+                       echo ---
+               fi
+               ;;
+
+       refs/heads/*)
+               branch="${1##refs/heads/}"
+               echo "New branch '$branch' available with the following commits:"
+               git-rev-list --pretty "$3"
+               ;;
+       esac
 else
        base=$(git-merge-base "$2" "$3")
        case "$base" in
        "$2")
+               git diff "$3" "^$base" | diffstat -p1
+               echo
                echo "New commits:"
                ;;
        *)
@@ -25,6 +84,6 @@ else
                ;;
        esac
        git-rev-list --pretty "$3" "^$base"
-fi |
-mail -s "Changes to ref $1" "$recipient"
+fi) |
+mail -s "$project: Changes to '${1##refs/heads/}'" $recipients
 exit 0