3 dgit - tutorial for package maintainers, using a workflow centered around git-debrebase(1)
7 This document describes elements of a workflow for maintaining a
8 non-native Debian package using B<dgit>. We maintain the Debian delta
9 as a series of git commits on our master branch. We use
10 git-debrebase(1) to shuffle our branch such that this series of git
11 commits appears at the end of the branch. All the public git history
12 is fast-forwarding, i.e., we do not rewrite and force-push.
14 Some advantages of this workflow:
20 Manipulate the delta queue using the full power of git-rebase(1),
21 instead of relying on quilt(1), and without having to switch back and
22 forth between patches-applied and patches-unapplied branches when
23 committing changes and trying to build, as with gbp-pq(1).
27 If you are using 3.0 (quilt), provide your delta queue as a properly
28 separated series of quilt patches in the source package that you
29 upload to the archive (unlike with dgit-maint-merge(7)).
33 Avoid the git tree being dirtied by the application or unapplication
34 of patches, as they are always applied.
38 Benefit from dgit's safety catches. In particular, ensure that your
39 upload always matches exactly your git HEAD.
43 Provide your full git history in a standard format on B<dgit-repos>,
44 where it can benefit downstream dgit users, such as people using dgit
45 to do an NMU (see dgit-nmu-simple(7) and dgit-user(7)).
49 Minimise the amount you need to know about 3.0 (quilt) in order to
50 maintain Debian source packages which use that format.
54 This workflow is appropriate for packages where the Debian delta
55 contains multiple pieces which interact, or which you don't expect to
56 be able to upstream soon. For packages with simple and/or short-lived
57 Debian deltas, use of git-debrebase(1) introduces unneeded complexity.
58 For such packages, consider the workflow described in
61 =head1 INITIAL DEBIANISATION
63 This section explains how to start using this workflow with a new
64 package. It should be skipped when converting an existing package to
67 =head2 When upstream tags releases in git
69 Suppose that the latest stable upstream release is 1.2.2, and this has
70 been tagged '1.2.2' by upstream.
74 % git clone -oupstream https://some.upstream/foo.git
76 % git verify-tag 1.2.2
77 % git reset --hard 1.2.2
78 % git branch --unset-upstream
82 The final command detaches your master branch from the upstream
83 remote, so that git doesn't try to push anything there, or merge
84 unreleased upstream commits. To maintain a copy of your packaging
85 branch on B<salsa.debian.org> in addition to B<dgit-repos>, you can do
90 % git remote add -f origin salsa.debian.org:Debian/foo.git
91 % git push --follow-tags -u origin master
95 Now go ahead and Debianise your package. Just make commits on the
96 master branch, adding things in the I<debian/> directory, or patching
99 Finally, you need an orig tarball:
107 See git-deborig(1) if this fails.
109 This tarball is ephemeral and easily regenerated, so we don't commit
110 it anywhere (e.g. with tools like pristine-tar(1)).
112 =head3 Verifying upstream's tarball releases
116 It can be a good idea to compare upstream's released tarballs with the
117 release tags, at least for the first upload of the package. If they
118 are different, you might need to add some additional steps to your
119 I<debian/rules>, such as running autotools.
121 A convenient way to perform this check is to import the tarball as
122 described in the following section, using a different value for
123 'upstream-tag', and then use git-diff(1) to compare the imported
124 tarball to the release tag. If they are the same, you can use
125 upstream's tarball instead of running git-deborig(1).
129 =head2 When upstream releases only tarballs
131 We need a virtual upstream branch with virtual release tags.
132 gbp-import-orig(1) can manage this for us. To begin
142 Now create I<debian/gbp.conf>:
147 upstream-branch = upstream
148 debian-branch = master
149 upstream-tag = %(version)s
153 pristine-tar-commit = False
160 gbp-import-orig(1) requires a pre-existing upstream branch:
164 % git add debian/gbp.conf && git commit -m "create gbp.conf"
165 % git checkout --orphan upstream
167 % git commit --allow-empty -m "initial, empty branch for upstream source"
168 % git checkout -f master
172 Then we can import the upstream version:
176 % gbp import-orig --merge-mode=replace ../foo_1.2.2.orig.tar.xz
180 Our upstream branch cannot be pushed to B<dgit-repos>, but since we
181 will need it whenever we import a new upstream version, we must push
182 it somewhere. The usual choice is B<salsa.debian.org>:
186 % git remote add -f origin salsa.debian.org:Debian/foo.git
187 % git push --follow-tags -u origin master upstream
191 You are now ready to proceed as above, making commits to the
192 I<debian/> directory and to the upstream source.
194 =head1 CONVERTING AN EXISTING PACKAGE
196 This section explains how to convert an existing Debian package to
197 this workflow. It should be skipped when debianising a new package.
199 =head2 No existing git history
205 % git remote add -f upstream https://some.upstream/foo.git
209 =head2 Existing git history using another workflow
211 First, if you don't already have the git history locally, clone it,
212 and obtain the corresponding orig.tar from the archive:
216 % git clone salsa.debian.org:Debian/foo
222 If your tree is patches-unapplied, you will need to make a commit
223 corresponding to each of the quilt patches. You can use
227 git debrebase convert-from-gbp
231 or manually with gbp-pq(1):
237 % git merge --ff-only patch-queue/master
242 Then make new upstream tags available:
246 % git remote add -f upstream https://some.upstream/foo.git
250 =for dgit-test dpkg-source-ignores begin
252 Now you simply need to ensure that your git HEAD is dgit-compatible,
253 i.e., it is exactly what you would get if you ran
254 B<dpkg-buildpackage -i'(?:^|/)\.git(?:/|$)' -I.git -S>
255 and then unpacked the resultant source package.
257 =for dgit-test dpkg-source-ignores end
259 To achieve this, you might need to delete
260 I<debian/source/local-options>. One way to have dgit check your
261 progress is to run B<dgit build-source>.
263 The first dgit push will require I<--overwrite>.
265 =head1 GIT CONFIGURATION
267 This workflow does not support using B<git merge> to merge divergent
268 branches of development (see "OTHER MERGES" in git-debrebase(5)). You
269 should configure git such that B<git pull> does not try to merge:
273 % git config --local pull.rebase true
277 Now when you pull work from other Debian contributors, git will rebase
278 your work on top of theirs.
280 If you use this repository for upstream development in addition to
281 Debian packaging work, you may not want to set this global setting.
282 Instead, see the B<branch.autoSetupRebase> and
283 B<branch.E<lt>nameE<gt>.rebase> settings in git-config(5).
285 =head1 IMPORTING NEW UPSTREAM RELEASES
287 There are two steps: obtaining git refs that correspond to the new
288 release, and importing that release using git-debrebase(1).
290 =head2 Obtaining the release
292 =head3 When upstream tags releases in git
300 =head3 When upstream releases only tarballs
302 You will need the I<debian/gbp.conf> from "When upstream releases only
303 tarballs", above. You will also need your upstream branch. Above, we
304 pushed this to B<salsa.debian.org>. You will need to clone or fetch
305 from there, instead of relying on B<dgit clone>/B<dgit fetch> alone.
311 % gbp import-orig --no-merge ../foo_1.2.3.orig.tar.xz
315 or if you have a working watch file
319 % gbp import-orig --no-merge --uscan
323 =head2 Importing the release
327 % git debrebase new-upstream-v0 1.2.3
328 % dch -v1.2.3-1 New upstream release.
329 % git add debian/changelog && git commit -m changelog
333 You can now review the merge of the new upstream release:
337 git diff debian/1.2.2-1..HEAD -- . ':!debian'
341 Pass I<--stat> just to see the list of changed files, which is useful
342 to determine whether there are any new or deleted files to may need
343 accounting for in your copyright file.
345 If you obtained a tarball from upstream, you are ready to try a build.
346 If you merged a git tag from upstream, you will first need to generate
355 =head1 EDITING THE DELTA QUEUE
357 =head2 Adding new patches
359 Adding new patches is straightforward: just make commits touching only
360 files outside of the I<debian/> directory. You can also use tools
361 like git-revert(1), git-am(1) and git-cherrypick(1).
363 =head2 Editing patches: starting a debrebase
365 git-debrebase(1) is a wrapper around git-rebase(1) which allows us to
366 edit, re-order and delete patches. Run
374 to start an interactive rebase. You can edit, re-order and delete
375 commits just as you would during B<git rebase -i>.
377 =head2 Editing patches: finishing a debrebase
379 After completing the git rebase, your branch will not be a
380 fast-forward of the git HEAD you had before the rebase. This means
381 that we cannot push the branch anywhere. If you are ready to upload,
382 B<dgit push> or B<dgit push-source> will take care of fixing this up
385 If you are not yet ready to upload, and want to push your branch to a
386 git remote such as B<salsa.debian.org>,
390 % git debrebase conclude
394 Note that each time you conclude a debrebase you introduce a
395 pseudomerge into your git history, which may make it harder to read.
396 Try to do all of the editing of the delta queue that you think will be
397 needed for this upload in a single debrebase, so that there is a
398 single debrebase stitch.
400 =head1 BUILDING AND UPLOADING
402 You can use dpkg-buildpackage(1) for test builds. When you are ready
403 to build for an upload, use B<dgit sbuild>.
405 Upload with B<dgit push> or B<dgit push-source>. Remember to pass
406 I<--new> if the package is new in the target suite.
408 Right before uploading, if you did not just already do so, you might
409 want to have git-debrebase(1) shuffle your branch such that the Debian
410 delta queue appears right at the tip of the branch you will push:
414 % git debrebase launder
419 Note that this will introduce a new pseudomerge.
421 After dgit pushing, be sure to git push to B<salsa.debian.org>, if
424 =head1 HANDLING DFSG-NON-FREE MATERIAL
426 This covers only DFSG-non-free material. Material which is legally
427 dangerous (for example, files which are actually illegal) cannot be
430 If you encounter possibly-legally-dangerous material in the upstream
431 source code you should seek advice. It is often best not to make a
432 fuss on a public mailing list (at least, not at first). Instead,
433 email your archive administrators. For Debian that is
434 To: dgit-owner@debian.org, ftpmaster@ftp-master.debian.org
436 =head2 When upstream tags releases in git
438 We create a DFSG-clean tag to import to master:
442 % git checkout -b pre-dfsg 1.2.3
444 % git commit -m "upstream version 1.2.3 DFSG-cleaned"
445 % git tag -s 1.2.3+dfsg
446 % git checkout master
447 % git branch -D pre-dfsg
451 =head2 When upstream releases only tarballs
453 The easiest way to handle this is to add a B<Files-Excluded> field to
454 I<debian/copyright>, and a B<uversionmangle> setting in
455 I<debian/watch>. See uscan(1). Alternatively, see the I<--filter>
456 option detailed in gbp-import-orig(1).
458 =head1 INCORPORATING NMUS
460 In the simplest case,
465 % git merge --ff-only dgit/dgit/sid
469 If that fails, because your branch and the NMUers work represent
470 divergent branches of development, you have a number of options. Here
471 we describe the two simplest.
473 =head2 Rebasing your work onto the NMU
477 % git rebase dgit/dgit/sid
481 If the NMUer added new commits modifying the upstream source, you will
482 probably want to debrebase before your next upload to tidy those up.
484 For example, the NMUer might have used git-revert(1) to unapply one of
485 your patches. A debrebase will strip both the patch and the reversion
486 from the delta queue.
488 =head2 Manually applying the debdiff
490 If you cannot rebase because you have already pushed to
491 B<salsa.debian.org>, say, you can manually apply the NMU debdiff,
492 commit and debrebase. The next B<dgit push> will require
495 =head1 HINTS AND TIPS
497 =head2 Minimising pseudomerges
499 Above we noted that each time you conclude a debrebase, you introduce
500 a pseudomerge into your git history, which may make it harder to read.
502 A convention you can use to minimise the number of pseudomerges is to
503 debrebase only right before you upload.
505 Before that point, instead of editing the existing delta queue, you
506 append fixup commits (and reversions of commits) that alter the
507 upstream source to the required state. You can freely push and pull
508 from B<salsa.debian.org> during this. Just before uploading, you
509 debrebase, once, to tidy everything up.
511 =head2 Upstream branches
513 Except in the case where upstream releases only tarballs, we do not
514 maintain a separate 'upstream' branch (unless you also happen to be
515 involved in upstream development). We work with upstream tags rather
516 than any branches, except temporary branches used to prepare patches
517 for forwarding upstream, for example.
519 The thought behind this is that branches are things to which one
520 expects to commit, while tags are immutable points in history. From
521 the Debian point of the view, the upstream source is immutable. It's
522 our packaging to which we expect to commit.
524 =head2 The first ever dgit push
526 If this is the first ever dgit push of the package, consider passing
527 I<--deliberately-not-fast-forward> instead of I<--overwrite>. This
528 avoids introducing a new origin commit into your git history. (This
529 origin commit would represent the most recent non-dgit upload of the
530 package, but this should already be represented in your git history.)
532 =head2 Alternative ways to start a debrebase
534 Above we started an interactive debrebase by invoking git-debrebase(1)
535 without any arguments, i.e.
543 It is also possible to perform a non-interactive rebase, like this:
547 % git debrebase -- [git-rebase options...]
552 A third alternative is to have git-debrebase(1) shuffle all the Debian
553 changes to the end of your branch, and then manipulate them yourself
554 using git-rebase(1) directly. For example,
558 % git debrebase launder
559 % git rebase -i HEAD~5 # there are 4 Debian patches
563 If you take this approach, you should be very careful not to start the
564 rebase earlier than the beginning of the delta queue.
572 This tutorial was written and is maintained by Sean Whitton
573 <spwhitton@spwhitton.name>. It contains contributions from other dgit
574 contributors too - see the dgit copyright file.