archive: handle commits with an empty tree
[git/jnareb-git.git] / contrib / hooks / post-receive-email
blobb2171a092eafef4cf1e5e1abfa37695a0c111927
1 #!/bin/sh
3 # Copyright (c) 2007 Andy Parkins
5 # An example hook script to mail out commit update information. This hook
6 # sends emails listing new revisions to the repository introduced by the
7 # change being reported. The rule is that (for branch updates) each commit
8 # will appear on one email and one email only.
10 # This hook is stored in the contrib/hooks directory. Your distribution
11 # will have put this somewhere standard. You should make this script
12 # executable then link to it in the repository you would like to use it in.
13 # For example, on debian the hook is stored in
14 # /usr/share/git-core/contrib/hooks/post-receive-email:
16 # chmod a+x post-receive-email
17 # cd /path/to/your/repository.git
18 # ln -sf /usr/share/git-core/contrib/hooks/post-receive-email hooks/post-receive
20 # This hook script assumes it is enabled on the central repository of a
21 # project, with all users pushing only to it and not between each other. It
22 # will still work if you don't operate in that style, but it would become
23 # possible for the email to be from someone other than the person doing the
24 # push.
26 # To help with debugging and use on pre-v1.5.1 git servers, this script will
27 # also obey the interface of hooks/update, taking its arguments on the
28 # command line. Unfortunately, hooks/update is called once for each ref.
29 # To avoid firing one email per ref, this script just prints its output to
30 # the screen when used in this mode. The output can then be redirected if
31 # wanted.
33 # Config
34 # ------
35 # hooks.mailinglist
36 # This is the list that all pushes will go to; leave it blank to not send
37 # emails for every ref update.
38 # hooks.announcelist
39 # This is the list that all pushes of annotated tags will go to. Leave it
40 # blank to default to the mailinglist field. The announce emails lists
41 # the short log summary of the changes since the last annotated tag.
42 # hooks.envelopesender
43 # If set then the -f option is passed to sendmail to allow the envelope
44 # sender address to be set
45 # hooks.emailprefix
46 # All emails have their subjects prefixed with this prefix, or "[SCM]"
47 # if emailprefix is unset, to aid filtering
48 # hooks.showrev
49 # The shell command used to format each revision in the email, with
50 # "%s" replaced with the commit id. Defaults to "git rev-list -1
51 # --pretty %s", displaying the commit id, author, date and log
52 # message. To list full patches separated by a blank line, you
53 # could set this to "git show -C %s; echo".
54 # To list a gitweb/cgit URL *and* a full patch for each change set, use this:
55 # "t=%s; printf 'http://.../?id=%%s' \$t; echo;echo; git show -C \$t; echo"
56 # Be careful if "..." contains things that will be expanded by shell "eval"
57 # or printf.
58 # hooks.emailmaxlines
59 # The maximum number of lines that should be included in the generated
60 # email body. If not specified, there is no limit.
61 # Lines beyond the limit are suppressed and counted, and a final
62 # line is added indicating the number of suppressed lines.
63 # hooks.diffopts
64 # Alternate options for the git diff-tree invocation that shows changes.
65 # Default is "--stat --summary --find-copies-harder". Add -p to those
66 # options to include a unified diff of changes in addition to the usual
67 # summary output.
69 # Notes
70 # -----
71 # All emails include the headers "X-Git-Refname", "X-Git-Oldrev",
72 # "X-Git-Newrev", and "X-Git-Reftype" to enable fine tuned filtering and
73 # give information for debugging.
76 # ---------------------------- Functions
79 # Function to prepare for email generation. This decides what type
80 # of update this is and whether an email should even be generated.
82 prep_for_email()
84 # --- Arguments
85 oldrev=$(git rev-parse $1)
86 newrev=$(git rev-parse $2)
87 refname="$3"
89 # --- Interpret
90 # 0000->1234 (create)
91 # 1234->2345 (update)
92 # 2345->0000 (delete)
93 if expr "$oldrev" : '0*$' >/dev/null
94 then
95 change_type="create"
96 else
97 if expr "$newrev" : '0*$' >/dev/null
98 then
99 change_type="delete"
100 else
101 change_type="update"
105 # --- Get the revision types
106 newrev_type=$(git cat-file -t $newrev 2> /dev/null)
107 oldrev_type=$(git cat-file -t "$oldrev" 2> /dev/null)
108 case "$change_type" in
109 create|update)
110 rev="$newrev"
111 rev_type="$newrev_type"
113 delete)
114 rev="$oldrev"
115 rev_type="$oldrev_type"
117 esac
119 # The revision type tells us what type the commit is, combined with
120 # the location of the ref we can decide between
121 # - working branch
122 # - tracking branch
123 # - unannoted tag
124 # - annotated tag
125 case "$refname","$rev_type" in
126 refs/tags/*,commit)
127 # un-annotated tag
128 refname_type="tag"
129 short_refname=${refname##refs/tags/}
131 refs/tags/*,tag)
132 # annotated tag
133 refname_type="annotated tag"
134 short_refname=${refname##refs/tags/}
135 # change recipients
136 if [ -n "$announcerecipients" ]; then
137 recipients="$announcerecipients"
140 refs/heads/*,commit)
141 # branch
142 refname_type="branch"
143 short_refname=${refname##refs/heads/}
145 refs/remotes/*,commit)
146 # tracking branch
147 refname_type="tracking branch"
148 short_refname=${refname##refs/remotes/}
149 echo >&2 "*** Push-update of tracking branch, $refname"
150 echo >&2 "*** - no email generated."
151 return 1
154 # Anything else (is there anything else?)
155 echo >&2 "*** Unknown type of update to $refname ($rev_type)"
156 echo >&2 "*** - no email generated"
157 return 1
159 esac
161 # Check if we've got anyone to send to
162 if [ -z "$recipients" ]; then
163 case "$refname_type" in
164 "annotated tag")
165 config_name="hooks.announcelist"
168 config_name="hooks.mailinglist"
170 esac
171 echo >&2 "*** $config_name is not set so no email will be sent"
172 echo >&2 "*** for $refname update $oldrev->$newrev"
173 return 1
176 return 0
180 # Top level email generation function. This calls the appropriate
181 # body-generation routine after outputting the common header.
183 # Note this function doesn't actually generate any email output, that is
184 # taken care of by the functions it calls:
185 # - generate_email_header
186 # - generate_create_XXXX_email
187 # - generate_update_XXXX_email
188 # - generate_delete_XXXX_email
189 # - generate_email_footer
191 # Note also that this function cannot 'exit' from the script; when this
192 # function is running (in hook script mode), the send_mail() function
193 # is already executing in another process, connected via a pipe, and
194 # if this function exits without, whatever has been generated to that
195 # point will be sent as an email... even if nothing has been generated.
197 generate_email()
199 # Email parameters
200 # The email subject will contain the best description of the ref
201 # that we can build from the parameters
202 describe=$(git describe $rev 2>/dev/null)
203 if [ -z "$describe" ]; then
204 describe=$rev
207 generate_email_header
209 # Call the correct body generation function
210 fn_name=general
211 case "$refname_type" in
212 "tracking branch"|branch)
213 fn_name=branch
215 "annotated tag")
216 fn_name=atag
218 esac
220 if [ -z "$maxlines" ]; then
221 generate_${change_type}_${fn_name}_email
222 else
223 generate_${change_type}_${fn_name}_email | limit_lines $maxlines
226 generate_email_footer
229 generate_email_header()
231 # --- Email (all stdout will be the email)
232 # Generate header
233 cat <<-EOF
234 To: $recipients
235 Subject: ${emailprefix}$projectdesc $refname_type $short_refname ${change_type}d. $describe
236 X-Git-Refname: $refname
237 X-Git-Reftype: $refname_type
238 X-Git-Oldrev: $oldrev
239 X-Git-Newrev: $newrev
241 This is an automated email from the git hooks/post-receive script. It was
242 generated because a ref change was pushed to the repository containing
243 the project "$projectdesc".
245 The $refname_type, $short_refname has been ${change_type}d
249 generate_email_footer()
251 SPACE=" "
252 cat <<-EOF
255 hooks/post-receive
256 --${SPACE}
257 $projectdesc
261 # --------------- Branches
264 # Called for the creation of a branch
266 generate_create_branch_email()
268 # This is a new branch and so oldrev is not valid
269 echo " at $newrev ($newrev_type)"
270 echo ""
272 echo $LOGBEGIN
273 show_new_revisions
274 echo $LOGEND
278 # Called for the change of a pre-existing branch
280 generate_update_branch_email()
282 # Consider this:
283 # 1 --- 2 --- O --- X --- 3 --- 4 --- N
285 # O is $oldrev for $refname
286 # N is $newrev for $refname
287 # X is a revision pointed to by some other ref, for which we may
288 # assume that an email has already been generated.
289 # In this case we want to issue an email containing only revisions
290 # 3, 4, and N. Given (almost) by
292 # git rev-list N ^O --not --all
294 # The reason for the "almost", is that the "--not --all" will take
295 # precedence over the "N", and effectively will translate to
297 # git rev-list N ^O ^X ^N
299 # So, we need to build up the list more carefully. git rev-parse
300 # will generate a list of revs that may be fed into git rev-list.
301 # We can get it to make the "--not --all" part and then filter out
302 # the "^N" with:
304 # git rev-parse --not --all | grep -v N
306 # Then, using the --stdin switch to git rev-list we have effectively
307 # manufactured
309 # git rev-list N ^O ^X
311 # This leaves a problem when someone else updates the repository
312 # while this script is running. Their new value of the ref we're
313 # working on would be included in the "--not --all" output; and as
314 # our $newrev would be an ancestor of that commit, it would exclude
315 # all of our commits. What we really want is to exclude the current
316 # value of $refname from the --not list, rather than N itself. So:
318 # git rev-parse --not --all | grep -v $(git rev-parse $refname)
320 # Get's us to something pretty safe (apart from the small time
321 # between refname being read, and git rev-parse running - for that,
322 # I give up)
325 # Next problem, consider this:
326 # * --- B --- * --- O ($oldrev)
328 # * --- X --- * --- N ($newrev)
330 # That is to say, there is no guarantee that oldrev is a strict
331 # subset of newrev (it would have required a --force, but that's
332 # allowed). So, we can't simply say rev-list $oldrev..$newrev.
333 # Instead we find the common base of the two revs and list from
334 # there.
336 # As above, we need to take into account the presence of X; if
337 # another branch is already in the repository and points at some of
338 # the revisions that we are about to output - we don't want them.
339 # The solution is as before: git rev-parse output filtered.
341 # Finally, tags: 1 --- 2 --- O --- T --- 3 --- 4 --- N
343 # Tags pushed into the repository generate nice shortlog emails that
344 # summarise the commits between them and the previous tag. However,
345 # those emails don't include the full commit messages that we output
346 # for a branch update. Therefore we still want to output revisions
347 # that have been output on a tag email.
349 # Luckily, git rev-parse includes just the tool. Instead of using
350 # "--all" we use "--branches"; this has the added benefit that
351 # "remotes/" will be ignored as well.
353 # List all of the revisions that were removed by this update, in a
354 # fast-forward update, this list will be empty, because rev-list O
355 # ^N is empty. For a non-fast-forward, O ^N is the list of removed
356 # revisions
357 fast_forward=""
358 rev=""
359 for rev in $(git rev-list $newrev..$oldrev)
361 revtype=$(git cat-file -t "$rev")
362 echo " discards $rev ($revtype)"
363 done
364 if [ -z "$rev" ]; then
365 fast_forward=1
368 # List all the revisions from baserev to newrev in a kind of
369 # "table-of-contents"; note this list can include revisions that
370 # have already had notification emails and is present to show the
371 # full detail of the change from rolling back the old revision to
372 # the base revision and then forward to the new revision
373 for rev in $(git rev-list $oldrev..$newrev)
375 revtype=$(git cat-file -t "$rev")
376 echo " via $rev ($revtype)"
377 done
379 if [ "$fast_forward" ]; then
380 echo " from $oldrev ($oldrev_type)"
381 else
382 # 1. Existing revisions were removed. In this case newrev
383 # is a subset of oldrev - this is the reverse of a
384 # fast-forward, a rewind
385 # 2. New revisions were added on top of an old revision,
386 # this is a rewind and addition.
388 # (1) certainly happened, (2) possibly. When (2) hasn't
389 # happened, we set a flag to indicate that no log printout
390 # is required.
392 echo ""
394 # Find the common ancestor of the old and new revisions and
395 # compare it with newrev
396 baserev=$(git merge-base $oldrev $newrev)
397 rewind_only=""
398 if [ "$baserev" = "$newrev" ]; then
399 echo "This update discarded existing revisions and left the branch pointing at"
400 echo "a previous point in the repository history."
401 echo ""
402 echo " * -- * -- N ($newrev)"
403 echo " \\"
404 echo " O -- O -- O ($oldrev)"
405 echo ""
406 echo "The removed revisions are not necessarily gone - if another reference"
407 echo "still refers to them they will stay in the repository."
408 rewind_only=1
409 else
410 echo "This update added new revisions after undoing existing revisions. That is"
411 echo "to say, the old revision is not a strict subset of the new revision. This"
412 echo "situation occurs when you --force push a change and generate a repository"
413 echo "containing something like this:"
414 echo ""
415 echo " * -- * -- B -- O -- O -- O ($oldrev)"
416 echo " \\"
417 echo " N -- N -- N ($newrev)"
418 echo ""
419 echo "When this happens we assume that you've already had alert emails for all"
420 echo "of the O revisions, and so we here report only the revisions in the N"
421 echo "branch from the common base, B."
425 echo ""
426 if [ -z "$rewind_only" ]; then
427 echo "Those revisions listed above that are new to this repository have"
428 echo "not appeared on any other notification email; so we list those"
429 echo "revisions in full, below."
431 echo ""
432 echo $LOGBEGIN
433 show_new_revisions
435 # XXX: Need a way of detecting whether git rev-list actually
436 # outputted anything, so that we can issue a "no new
437 # revisions added by this update" message
439 echo $LOGEND
440 else
441 echo "No new revisions were added by this update."
444 # The diffstat is shown from the old revision to the new revision.
445 # This is to show the truth of what happened in this change.
446 # There's no point showing the stat from the base to the new
447 # revision because the base is effectively a random revision at this
448 # point - the user will be interested in what this revision changed
449 # - including the undoing of previous revisions in the case of
450 # non-fast-forward updates.
451 echo ""
452 echo "Summary of changes:"
453 git diff-tree $diffopts $oldrev..$newrev
457 # Called for the deletion of a branch
459 generate_delete_branch_email()
461 echo " was $oldrev"
462 echo ""
463 echo $LOGBEGIN
464 git show -s --pretty=oneline $oldrev
465 echo $LOGEND
468 # --------------- Annotated tags
471 # Called for the creation of an annotated tag
473 generate_create_atag_email()
475 echo " at $newrev ($newrev_type)"
477 generate_atag_email
481 # Called for the update of an annotated tag (this is probably a rare event
482 # and may not even be allowed)
484 generate_update_atag_email()
486 echo " to $newrev ($newrev_type)"
487 echo " from $oldrev (which is now obsolete)"
489 generate_atag_email
493 # Called when an annotated tag is created or changed
495 generate_atag_email()
497 # Use git for-each-ref to pull out the individual fields from the
498 # tag
499 eval $(git for-each-ref --shell --format='
500 tagobject=%(*objectname)
501 tagtype=%(*objecttype)
502 tagger=%(taggername)
503 tagged=%(taggerdate)' $refname
506 echo " tagging $tagobject ($tagtype)"
507 case "$tagtype" in
508 commit)
510 # If the tagged object is a commit, then we assume this is a
511 # release, and so we calculate which tag this tag is
512 # replacing
513 prevtag=$(git describe --abbrev=0 $newrev^ 2>/dev/null)
515 if [ -n "$prevtag" ]; then
516 echo " replaces $prevtag"
520 echo " length $(git cat-file -s $tagobject) bytes"
522 esac
523 echo " tagged by $tagger"
524 echo " on $tagged"
526 echo ""
527 echo $LOGBEGIN
529 # Show the content of the tag message; this might contain a change
530 # log or release notes so is worth displaying.
531 git cat-file tag $newrev | sed -e '1,/^$/d'
533 echo ""
534 case "$tagtype" in
535 commit)
536 # Only commit tags make sense to have rev-list operations
537 # performed on them
538 if [ -n "$prevtag" ]; then
539 # Show changes since the previous release
540 git rev-list --pretty=short "$prevtag..$newrev" | git shortlog
541 else
542 # No previous tag, show all the changes since time
543 # began
544 git rev-list --pretty=short $newrev | git shortlog
548 # XXX: Is there anything useful we can do for non-commit
549 # objects?
551 esac
553 echo $LOGEND
557 # Called for the deletion of an annotated tag
559 generate_delete_atag_email()
561 echo " was $oldrev"
562 echo ""
563 echo $LOGBEGIN
564 git show -s --pretty=oneline $oldrev
565 echo $LOGEND
568 # --------------- General references
571 # Called when any other type of reference is created (most likely a
572 # non-annotated tag)
574 generate_create_general_email()
576 echo " at $newrev ($newrev_type)"
578 generate_general_email
582 # Called when any other type of reference is updated (most likely a
583 # non-annotated tag)
585 generate_update_general_email()
587 echo " to $newrev ($newrev_type)"
588 echo " from $oldrev"
590 generate_general_email
594 # Called for creation or update of any other type of reference
596 generate_general_email()
598 # Unannotated tags are more about marking a point than releasing a
599 # version; therefore we don't do the shortlog summary that we do for
600 # annotated tags above - we simply show that the point has been
601 # marked, and print the log message for the marked point for
602 # reference purposes
604 # Note this section also catches any other reference type (although
605 # there aren't any) and deals with them in the same way.
607 echo ""
608 if [ "$newrev_type" = "commit" ]; then
609 echo $LOGBEGIN
610 git show --no-color --root -s --pretty=medium $newrev
611 echo $LOGEND
612 else
613 # What can we do here? The tag marks an object that is not
614 # a commit, so there is no log for us to display. It's
615 # probably not wise to output git cat-file as it could be a
616 # binary blob. We'll just say how big it is
617 echo "$newrev is a $newrev_type, and is $(git cat-file -s $newrev) bytes long."
622 # Called for the deletion of any other type of reference
624 generate_delete_general_email()
626 echo " was $oldrev"
627 echo ""
628 echo $LOGBEGIN
629 git show -s --pretty=oneline $oldrev
630 echo $LOGEND
634 # --------------- Miscellaneous utilities
637 # Show new revisions as the user would like to see them in the email.
639 show_new_revisions()
641 # This shows all log entries that are not already covered by
642 # another ref - i.e. commits that are now accessible from this
643 # ref that were previously not accessible
644 # (see generate_update_branch_email for the explanation of this
645 # command)
647 # Revision range passed to rev-list differs for new vs. updated
648 # branches.
649 if [ "$change_type" = create ]
650 then
651 # Show all revisions exclusive to this (new) branch.
652 revspec=$newrev
653 else
654 # Branch update; show revisions not part of $oldrev.
655 revspec=$oldrev..$newrev
658 other_branches=$(git for-each-ref --format='%(refname)' refs/heads/ |
659 grep -F -v $refname)
660 git rev-parse --not $other_branches |
661 if [ -z "$custom_showrev" ]
662 then
663 git rev-list --pretty --stdin $revspec
664 else
665 git rev-list --stdin $revspec |
666 while read onerev
668 eval $(printf "$custom_showrev" $onerev)
669 done
674 limit_lines()
676 lines=0
677 skipped=0
678 while IFS="" read -r line; do
679 lines=$((lines + 1))
680 if [ $lines -gt $1 ]; then
681 skipped=$((skipped + 1))
682 else
683 printf "%s\n" "$line"
685 done
686 if [ $skipped -ne 0 ]; then
687 echo "... $skipped lines suppressed ..."
692 send_mail()
694 if [ -n "$envelopesender" ]; then
695 /usr/sbin/sendmail -t -f "$envelopesender"
696 else
697 /usr/sbin/sendmail -t
701 # ---------------------------- main()
703 # --- Constants
704 LOGBEGIN="- Log -----------------------------------------------------------------"
705 LOGEND="-----------------------------------------------------------------------"
707 # --- Config
708 # Set GIT_DIR either from the working directory, or from the environment
709 # variable.
710 GIT_DIR=$(git rev-parse --git-dir 2>/dev/null)
711 if [ -z "$GIT_DIR" ]; then
712 echo >&2 "fatal: post-receive: GIT_DIR not set"
713 exit 1
716 projectdesc=$(sed -ne '1p' "$GIT_DIR/description" 2>/dev/null)
717 # Check if the description is unchanged from it's default, and shorten it to
718 # a more manageable length if it is
719 if expr "$projectdesc" : "Unnamed repository.*$" >/dev/null
720 then
721 projectdesc="UNNAMED PROJECT"
724 recipients=$(git config hooks.mailinglist)
725 announcerecipients=$(git config hooks.announcelist)
726 envelopesender=$(git config hooks.envelopesender)
727 emailprefix=$(git config hooks.emailprefix || echo '[SCM] ')
728 custom_showrev=$(git config hooks.showrev)
729 maxlines=$(git config hooks.emailmaxlines)
730 diffopts=$(git config hooks.diffopts)
731 : ${diffopts:="--stat --summary --find-copies-harder"}
733 # --- Main loop
734 # Allow dual mode: run from the command line just like the update hook, or
735 # if no arguments are given then run as a hook script
736 if [ -n "$1" -a -n "$2" -a -n "$3" ]; then
737 # Output to the terminal in command line mode - if someone wanted to
738 # resend an email; they could redirect the output to sendmail
739 # themselves
740 prep_for_email $2 $3 $1 && PAGER= generate_email
741 else
742 while read oldrev newrev refname
744 prep_for_email $oldrev $newrev $refname || continue
745 generate_email $maxlines | send_mail
746 done