post-receive-email example hook: fastforward should have been fast_forward
[git/git.git] / contrib / hooks / post-receive-email
1 #!/bin/sh
2 #
3 # Copyright (c) 2007 Andy Parkins
4 #
5 # An example hook script to mail out commit update information. This hook sends emails
6 # listing new revisions to the repository introduced by the change being reported. The
7 # rule is that (for branch updates) each commit will appear on one email and one email
8 # only.
9 #
10 # This hook is stored in the contrib/hooks directory. Your distribution will have put
11 # this somewhere standard. You should make this script executable then link to it in
12 # the repository you would like to use it in. For example, on debian the hook is stored
13 # in /usr/share/doc/git-core/contrib/hooks/post-receive-email:
14 #
15 # chmod a+x post-receive-email
16 # cd /path/to/your/repository.git
17 # ln -sf /usr/share/doc/git-core/contrib/hooks/post-receive-email hooks/post-receive
18 #
19 # This hook script assumes it is enabled on the central repository of a project, with
20 # all users pushing only to it and not between each other. It will still work if you
21 # don't operate in that style, but it would become possible for the email to be from
22 # someone other than the person doing the push.
23 #
24 # Config
25 # ------
26 # hooks.mailinglist
27 # This is the list that all pushes will go to; leave it blank to not send
28 # emails for every ref update.
29 # hooks.announcelist
30 # This is the list that all pushes of annotated tags will go to. Leave it
31 # blank to default to the mailinglist field. The announce emails lists the
32 # short log summary of the changes since the last annotated tag.
33 # hook.envelopesender
34 # If set then the -f option is passed to sendmail to allow the envelope sender
35 # address to be set
36 #
37 # Notes
38 # -----
39 # All emails have their subjects prefixed with "[SCM]" to aid filtering.
40 # All emails include the headers "X-Git-Refname", "X-Git-Oldrev",
41 # "X-Git-Newrev", and "X-Git-Reftype" to enable fine tuned filtering and
42 # give information for debugging.
43 #
44
45 # ---------------------------- Functions
46
47 #
48 # Top level email generation function. This decides what type of update
49 # this is and calls the appropriate body-generation routine after outputting
50 # the common header
51 #
52 # Note this function doesn't actually generate any email output, that is taken
53 # care of by the functions it calls:
54 # - generate_email_header
55 # - generate_create_XXXX_email
56 # - generate_update_XXXX_email
57 # - generate_delete_XXXX_email
58 # - generate_email_footer
59 #
60 generate_email()
61 {
62 # --- Arguments
63 oldrev=$(git rev-parse $1)
64 newrev=$(git rev-parse $2)
65 refname="$3"
66
67 # --- Interpret
68 # 0000->1234 (create)
69 # 1234->2345 (update)
70 # 2345->0000 (delete)
71 if expr "$oldrev" : '0*$' >/dev/null
72 then
73 change_type="create"
74 else
75 if expr "$newrev" : '0*$' >/dev/null
76 then
77 change_type="delete"
78 else
79 change_type="update"
80 fi
81 fi
82
83 # --- Get the revision types
84 newrev_type=$(git cat-file -t $newrev 2> /dev/null)
85 oldrev_type=$(git cat-file -t "$oldrev" 2> /dev/null)
86 case "$change_type" in
87 create|update)
88 rev="$newrev"
89 rev_type="$newrev_type"
90 ;;
91 delete)
92 rev="$oldrev"
93 rev_type="$oldrev_type"
94 ;;
95 esac
96
97 # The revision type tells us what type the commit is, combined with
98 # the location of the ref we can decide between
99 # - working branch
100 # - tracking branch
101 # - unannoted tag
102 # - annotated tag
103 case "$refname","$rev_type" in
104 refs/tags/*,commit)
105 # un-annotated tag
106 refname_type="tag"
107 short_refname=${refname##refs/tags/}
108 ;;
109 refs/tags/*,tag)
110 # annotated tag
111 refname_type="annotated tag"
112 short_refname=${refname##refs/tags/}
113 # change recipients
114 if [ -n "$announcerecipients" ]; then
115 recipients="$announcerecipients"
116 fi
117 ;;
118 refs/heads/*,commit)
119 # branch
120 refname_type="branch"
121 short_refname=${refname##refs/heads/}
122 ;;
123 refs/remotes/*,commit)
124 # tracking branch
125 refname_type="tracking branch"
126 short_refname=${refname##refs/remotes/}
127 echo >&2 "*** Push-update of tracking branch, $refname"
128 echo >&2 "*** - no email generated."
129 exit 0
130 ;;
131 *)
132 # Anything else (is there anything else?)
133 echo >&2 "*** Unknown type of update to $refname ($rev_type)"
134 echo >&2 "*** - no email generated"
135 exit 1
136 ;;
137 esac
138
139 # Check if we've got anyone to send to
140 if [ -z "$recipients" ]; then
141 echo >&2 "*** hooks.recipients is not set so no email will be sent"
142 echo >&2 "*** for $refname update $oldrev->$newrev"
143 exit 0
144 fi
145
146 # Email parameters
147 # The committer will be obtained from the latest existing rev; so
148 # for a deletion it will be the oldrev, for the others, then newrev
149 committer=$(git show --pretty=full -s $rev | sed -ne "s/^Commit: //p" |
150 sed -ne 's/\(.*\) </"\1" </p')
151 # The email subject will contain the best description of the ref
152 # that we can build from the parameters
153 describe=$(git describe $rev 2>/dev/null)
154 if [ -z "$describe" ]; then
155 describe=$rev
156 fi
157
158 generate_email_header
159
160 # Call the correct body generation function
161 fn_name=general
162 case "$refname_type" in
163 "tracking branch"|branch)
164 fn_name=branch
165 ;;
166 "annotated tag")
167 fn_name=atag
168 ;;
169 esac
170 generate_${change_type}_${fn_name}_email
171
172 generate_email_footer
173 }
174
175 generate_email_header()
176 {
177 # --- Email (all stdout will be the email)
178 # Generate header
179 cat <<-EOF
180 From: $committer
181 To: $recipients
182 Subject: ${EMAILPREFIX}$projectdesc $refname_type, $short_refname, ${change_type}d. $describe
183 X-Git-Refname: $refname
184 X-Git-Reftype: $refname_type
185 X-Git-Oldrev: $oldrev
186 X-Git-Newrev: $newrev
187
188 This is an automated email from the git hooks/post-receive script. It was
189 generated because a ref change was pushed to the repository containing
190 the project "$projectdesc".
191
192 The $refname_type, $short_refname has been ${change_type}d
193 EOF
194 }
195
196 generate_email_footer()
197 {
198 cat <<-EOF
199
200
201 hooks/post-receive
202 --
203 $projectdesc
204 EOF
205 }
206
207 # --------------- Branches
208
209 #
210 # Called for the creation of a branch
211 #
212 generate_create_branch_email()
213 {
214 # This is a new branch and so oldrev is not valid
215 echo " at $newrev ($newrev_type)"
216 echo ""
217
218 echo $LOGBEGIN
219 # This shows all log entries that are not already covered by
220 # another ref - i.e. commits that are now accessible from this
221 # ref that were previously not accessible (see generate_update_branch_email
222 # for the explanation of this command)
223 git rev-parse --not --branches | grep -v $(git rev-parse $refname) |
224 git rev-list --pretty --stdin $newrev
225 echo $LOGEND
226 }
227
228 #
229 # Called for the change of a pre-existing branch
230 #
231 generate_update_branch_email()
232 {
233 # Consider this:
234 # 1 --- 2 --- O --- X --- 3 --- 4 --- N
235 #
236 # O is $oldrev for $refname
237 # N is $newrev for $refname
238 # X is a revision pointed to by some other ref, for which we may
239 # assume that an email has already been generated.
240 # In this case we want to issue an email containing only revisions
241 # 3, 4, and N. Given (almost) by
242 #
243 # git-rev-list N ^O --not --all
244 #
245 # The reason for the "almost", is that the "--not --all" will take
246 # precedence over the "N", and effectively will translate to
247 #
248 # git-rev-list N ^O ^X ^N
249 #
250 # So, we need to build up the list more carefully. git-rev-parse will
251 # generate a list of revs that may be fed into git-rev-list. We can get
252 # it to make the "--not --all" part and then filter out the "^N" with:
253 #
254 # git-rev-parse --not --all | grep -v N
255 #
256 # Then, using the --stdin switch to git-rev-list we have effectively
257 # manufactured
258 #
259 # git-rev-list N ^O ^X
260 #
261 # This leaves a problem when someone else updates the repository
262 # while this script is running. Their new value of the ref we're working
263 # on would be included in the "--not --all" output; and as our $newrev
264 # would be an ancestor of that commit, it would exclude all of our
265 # commits. What we really want is to exclude the current value of
266 # $refname from the --not list, rather than N itself. So:
267 #
268 # git-rev-parse --not --all | grep -v $(git-rev-parse $refname)
269 #
270 # Get's us to something pretty safe (apart from the small time between
271 # refname being read, and git-rev-parse running - for that, I give up)
272 #
273 #
274 # Next problem, consider this:
275 # * --- B --- * --- O ($oldrev)
276 # \
277 # * --- X --- * --- N ($newrev)
278 #
279 # That is to say, there is no guarantee that oldrev is a strict subset of
280 # newrev (it would have required a --force, but that's allowed). So, we
281 # can't simply say rev-list $oldrev..$newrev. Instead we find the common
282 # base of the two revs and list from there.
283 #
284 # As above, we need to take into account the presence of X; if another
285 # branch is already in the repository and points at some of the revisions
286 # that we are about to output - we don't want them. The solution is as
287 # before: git-rev-parse output filtered.
288 #
289 # Finally, tags:
290 # 1 --- 2 --- O --- T --- 3 --- 4 --- N
291 #
292 # Tags pushed into the repository generate nice shortlog emails that
293 # summarise the commits between them and the previous tag. However,
294 # those emails don't include the full commit messages that we output
295 # for a branch update. Therefore we still want to output revisions
296 # that have been output on a tag email.
297 #
298 # Luckily, git-rev-parse includes just the tool. Instead of using "--all"
299 # we use "--branches"; this has the added benefit that "remotes/" will
300 # be ignored as well.
301
302 # List all of the revisions that were removed by this update, in a fast forward
303 # update, this list will be empty, because rev-list O ^N is empty. For a non
304 # fast forward, O ^N is the list of removed revisions
305 fast_forward=""
306 rev=""
307 for rev in $(git rev-list $newrev..$oldrev)
308 do
309 revtype=$(git cat-file -t "$rev")
310 echo " discards $rev ($revtype)"
311 done
312 if [ -z "$rev" ]; then
313 fast_forward=1
314 fi
315
316 # List all the revisions from baserev to newrev in a kind of
317 # "table-of-contents"; note this list can include revisions that have
318 # already had notification emails and is present to show the full detail
319 # of the change from rolling back the old revision to the base revision and
320 # then forward to the new revision
321 for rev in $(git rev-list $oldrev..$newrev)
322 do
323 revtype=$(git cat-file -t "$rev")
324 echo " via $rev ($revtype)"
325 done
326
327 if [ -z "$fastforward" ]; then
328 echo " from $oldrev ($oldrev_type)"
329 else
330 echo ""
331 echo "This update added new revisions after undoing old revisions. That is to"
332 echo "say, the old revision is not a strict subset of the new revision. This"
333 echo "situation occurs when you --force push a change and generate a"
334 echo "repository containing something like this:"
335 echo ""
336 echo " * -- * -- B -- O -- O -- O ($oldrev)"
337 echo " \\"
338 echo " N -- N -- N ($newrev)"
339 echo ""
340 echo "When this happens we assume that you've already had alert emails for all"
341 echo "of the O revisions, and so we here report only the revisions in the N"
342 echo "branch from the common base, B."
343 fi
344
345 echo ""
346 echo "Those revisions listed above that are new to this repository have"
347 echo "not appeared on any other notification email; so we list those"
348 echo "revisions in full, below."
349
350 echo ""
351 echo $LOGBEGIN
352 git rev-parse --not --branches | grep -v $(git rev-parse $refname) |
353 git rev-list --pretty --stdin $oldrev..$newrev
354
355 # XXX: Need a way of detecting whether git rev-list actually outputted
356 # anything, so that we can issue a "no new revisions added by this
357 # update" message
358
359 echo $LOGEND
360
361 # The diffstat is shown from the old revision to the new revision. This
362 # is to show the truth of what happened in this change. There's no point
363 # showing the stat from the base to the new revision because the base
364 # is effectively a random revision at this point - the user will be
365 # interested in what this revision changed - including the undoing of
366 # previous revisions in the case of non-fast forward updates.
367 echo ""
368 echo "Summary of changes:"
369 git diff-tree --stat --summary --find-copies-harder $oldrev..$newrev
370 }
371
372 #
373 # Called for the deletion of a branch
374 #
375 generate_delete_branch_email()
376 {
377 echo " was $oldrev"
378 echo ""
379 echo $LOGEND
380 git show -s --pretty=oneline $oldrev
381 echo $LOGEND
382 }
383
384 # --------------- Annotated tags
385
386 #
387 # Called for the creation of an annotated tag
388 #
389 generate_create_atag_email()
390 {
391 echo " at $newrev ($newrev_type)"
392
393 generate_atag_email
394 }
395
396 #
397 # Called for the update of an annotated tag (this is probably a rare event
398 # and may not even be allowed)
399 #
400 generate_update_atag_email()
401 {
402 echo " to $newrev ($newrev_type)"
403 echo " from $oldrev (which is now obsolete)"
404
405 generate_atag_email
406 }
407
408 #
409 # Called when an annotated tag is created or changed
410 #
411 generate_atag_email()
412 {
413 # Use git-for-each-ref to pull out the individual fields from the tag
414 eval $(git for-each-ref --shell --format='
415 tagobject=%(*objectname)
416 tagtype=%(*objecttype)
417 tagger=%(taggername)
418 tagged=%(taggerdate)' $refname
419 )
420
421 echo " tagging $tagobject ($tagtype)"
422 case "$tagtype" in
423 commit)
424 # If the tagged object is a commit, then we assume this is a
425 # release, and so we calculate which tag this tag is replacing
426 prevtag=$(git describe --abbrev=0 $newrev^ 2>/dev/null)
427
428 if [ -n "$prevtag" ]; then
429 echo " replaces $prevtag"
430 fi
431 ;;
432 *)
433 echo " length $(git cat-file -s $tagobject) bytes"
434 ;;
435 esac
436 echo " tagged by $tagger"
437 echo " on $tagged"
438
439 echo ""
440 echo $LOGBEGIN
441
442 # Show the content of the tag message; this might contain a change log
443 # or release notes so is worth displaying.
444 git cat-file tag $newrev | sed -e '1,/^$/d'
445
446 echo ""
447 case "$tagtype" in
448 commit)
449 # Only commit tags make sense to have rev-list operations performed
450 # on them
451 if [ -n "$prevtag" ]; then
452 # Show changes since the previous release
453 git rev-list --pretty=short "$prevtag..$newrev" | git shortlog
454 else
455 # No previous tag, show all the changes since time began
456 git rev-list --pretty=short $newrev | git shortlog
457 fi
458 ;;
459 *)
460 # XXX: Is there anything useful we can do for non-commit objects?
461 ;;
462 esac
463
464 echo $LOGEND
465 }
466
467 #
468 # Called for the deletion of an annotated tag
469 #
470 generate_delete_atag_email()
471 {
472 echo " was $oldrev"
473 echo ""
474 echo $LOGEND
475 git show -s --pretty=oneline $oldrev
476 echo $LOGEND
477 }
478
479 # --------------- General references
480
481 #
482 # Called when any other type of reference is created (most likely a
483 # non-annotated tag)
484 #
485 generate_create_general_email()
486 {
487 echo " at $newrev ($newrev_type)"
488
489 generate_general_email
490 }
491
492 #
493 # Called when any other type of reference is updated (most likely a
494 # non-annotated tag)
495 #
496 generate_update_general_email()
497 {
498 echo " to $newrev ($newrev_type)"
499 echo " from $oldrev"
500
501 generate_general_email
502 }
503
504 #
505 # Called for creation or update of any other type of reference
506 #
507 generate_general_email()
508 {
509 # Unannotated tags are more about marking a point than releasing a version;
510 # therefore we don't do the shortlog summary that we do for annotated tags
511 # above - we simply show that the point has been marked, and print the log
512 # message for the marked point for reference purposes
513 #
514 # Note this section also catches any other reference type (although there
515 # aren't any) and deals with them in the same way.
516
517 echo ""
518 if [ "$newrev_type" = "commit" ]; then
519 echo $LOGBEGIN
520 git show --no-color --root -s $newrev
521 echo $LOGEND
522 else
523 # What can we do here? The tag marks an object that is not a commit,
524 # so there is no log for us to display. It's probably not wise to
525 # output git-cat-file as it could be a binary blob. We'll just say how
526 # big it is
527 echo "$newrev is a $newrev_type, and is $(git cat-file -s $newrev) bytes long."
528 fi
529 }
530
531 #
532 # Called for the deletion of any other type of reference
533 #
534 generate_delete_general_email()
535 {
536 echo " was $oldrev"
537 echo ""
538 echo $LOGEND
539 git show -s --pretty=oneline $oldrev
540 echo $LOGEND
541 }
542
543 # ---------------------------- main()
544
545 # --- Constants
546 EMAILPREFIX="[SCM] "
547 LOGBEGIN="- Log -----------------------------------------------------------------"
548 LOGEND="-----------------------------------------------------------------------"
549
550 # --- Config
551 # Set GIT_DIR either from the working directory, or from the environment
552 # variable.
553 GIT_DIR=$(git rev-parse --git-dir 2>/dev/null)
554 if [ -z "$GIT_DIR" ]; then
555 echo >&2 "fatal: post-receive: GIT_DIR not set"
556 exit 1
557 fi
558
559 projectdesc=$(sed -e '1p' "$GIT_DIR/description")
560 # Check if the description is unchanged from it's default, and shorten it to a
561 # more manageable length if it is
562 if expr "$projectdesc" : "Unnamed repository.*$" >/dev/null
563 then
564 projectdesc="UNNAMED PROJECT"
565 fi
566
567 recipients=$(git repo-config hooks.mailinglist)
568 announcerecipients=$(git repo-config hooks.announcelist)
569 envelopesender=$(git-repo-config hooks.envelopesender)
570
571 # --- Main loop
572 # Allow dual mode: run from the command line just like the update hook, or if
573 # no arguments are given then run as a hook script
574 if [ -n "$1" -a -n "$2" -a -n "$3" ]; then
575 # Output to the terminal in command line mode - if someone wanted to
576 # resend an email; they could redirect the output to sendmail themselves
577 PAGER= generate_email $2 $3 $1
578 else
579 if [ -n "$envelopesender" ]; then
580 envelopesender="-f '$envelopesender'"
581 fi
582
583 while read oldrev newrev refname
584 do
585 generate_email $oldrev $newrev $refname |
586 /usr/sbin/sendmail -t $envelopesender
587 done
588 fi