1dgit-maint-merge(7) dgit dgit-maint-merge(7)
2
6 dgit - tutorial for package maintainers, using a workflow centered
7 around git-merge(1)
8
10 This document describes elements of a workflow for maintaining a non-
11 native Debian package using dgit. The workflow makes the following
12 opinionated assumptions:
13 • Git histories should be the non-linear histories produced by
15 git-merge(1), preserving all information about divergent
16 development that was later brought together.
17 • Maintaining convenient and powerful git workflows takes priority
19 over the usefulness of the raw Debian source package. The Debian
20 archive is thought of as an output format.
21 For example, we don't spend time curating a series of quilt
23 patches. However, in straightforward cases, the information such a
24 series would contain is readily available from dgit-repos.
25 • It is more important to have the Debian package's git history be a
27 descendent of upstream's git history than to use exactly the
28 orig.tar that upstream makes available for download.
29 This workflow is less suitable for some packages. When the Debian
31 delta contains multiple pieces which interact, or which you aren't
32 going to be able to upstream soon, it might be preferable to maintain
33 the delta as a rebasing patch series. For such a workflow see for
34 example dgit-maint-debrebase(7) and dgit-maint-gbp(7).
35
37 This section explains how to start using this workflow with a new
38 package. It should be skipped when converting an existing package to
39 this workflow.
40 When upstream tags releases in git
42 Suppose that the latest stable upstream release is 1.2.2, and this has
43 been tagged '1.2.2' by upstream.
44 % git clone -oupstream https://some.upstream/foo.git
46 % cd foo
47 % git verify-tag 1.2.2
48 % git reset --hard 1.2.2
49 % git branch --unset-upstream
50 The final command detaches your master branch from the upstream remote,
52 so that git doesn't try to push anything there, or merge unreleased
53 upstream commits. If you want to maintain a copy of your packaging
54 branch on salsa.debian.org in addition to dgit-repos, you can do
55 something like this:
56 % git remote add -f origin salsa.debian.org:Debian/foo.git
58 % git push --follow-tags -u origin master
59 Now go ahead and Debianise your package. Just make commits on the
61 master branch, adding things in the debian/ directory. If you need to
62 patch the upstream source, just make commits that change files outside
63 of the debian/ directory. It is best to separate commits that touch
64 debian/ from commits that touch upstream source, so that the latter can
65 be cherry-picked by upstream.
66 Note that there is no need to maintain a separate 'upstream' branch,
68 unless you also happen to be involved in upstream development. We work
69 with upstream tags rather than any branches, except when forwarding
70 patches (see FORWARDING PATCHES UPSTREAM, below).
71 Finally, you need an orig tarball:
73 % git deborig
75 See git-deborig(1) if this fails.
77 This tarball is ephemeral and easily regenerated, so we don't commit it
79 anywhere (e.g. with tools like pristine-tar(1)).
80 Verifying upstream's tarball releases
82 It can be a good idea to compare upstream's released tarballs with
84 the release tags, at least for the first upload of the package. If
85 they are different, you might need to add some additional steps to
86 your debian/rules, such as running autotools.
87 A convenient way to perform this check is to import the tarball as
89 described in the following section, using a different value for
90 'upstream-tag', and then use git-diff(1) to compare the imported
91 tarball to the release tag. If they are the same, you can use
92 upstream's tarball instead of running git-deborig(1).
93 Using untagged upstream commits
95 Sometimes upstream does not tag their releases, or you want to
97 package an unreleased git snapshot. In such a case you can create
98 your own upstream release tag, of the form upstream/ver, where ver
99 is the upstream version you plan to put in debian/changelog. The
100 upstream/ prefix ensures that your tag will not clash with any tags
101 upstream later creates.
102 For example, suppose that the latest upstream release is 1.2.2 and
104 you want to package git commit ab34c21 which was made on
105 2013-12-11. A common convention is to use the upstream version
106 number 1.2.2+git20131211.ab34c21 and so you could use
107 % git tag -s upstream/1.2.2+git20131211.ab34c21 ab34c21
109 to obtain a release tag, and then proceed as above.
111 One can generate such a versioned tag using git show's --pretty
113 option. e.g.:
114 % git tag -s upstream/$(git show --date=format:%Y%m%d --pretty=format:"1.2.2+git%cd.%h" --quiet upstream/main) upstream/main
116 When upstream releases only tarballs
118 We need a virtual upstream branch with virtual release tags.
119 gbp-import-orig(1) can manage this for us. To begin
120 % mkdir foo
122 % cd foo
123 % git init
124 Now create debian/gbp.conf:
126 [DEFAULT]
128 upstream-branch = upstream
129 debian-branch = master
130 upstream-tag = upstream/%(version)s
131 sign-tags = True
133 pristine-tar = False
134 pristine-tar-commit = False
135 [import-orig]
137 merge-mode = merge
138 merge = False
139 gbp-import-orig(1) requires a pre-existing upstream branch:
141 % git add debian/gbp.conf && git commit -m "create gbp.conf"
143 % git checkout --orphan upstream
144 % git rm -rf .
145 % git commit --allow-empty -m "initial, empty branch for upstream source"
146 % git checkout -f master
147 Then we can import the upstream version:
149 % gbp import-orig --merge --merge-mode=replace ../foo_1.2.2.orig.tar.xz
151 Our upstream branch cannot be pushed to dgit-repos, but since we will
153 need it whenever we import a new upstream version, we must push it
154 somewhere. The usual choice is salsa.debian.org:
155 % git remote add -f origin salsa.debian.org:Debian/foo.git
157 % git push --follow-tags -u origin master upstream
158 You are now ready to proceed as above, making commits to both the
160 upstream source and the debian/ directory.
161
163 This section explains how to convert an existing Debian package to this
164 workflow. It should be skipped when debianising a new package.
165 No existing git history
167 % dgit clone foo
168 % cd foo
169 % git remote add -f upstream https://some.upstream/foo.git
170 Existing git history using another workflow
172 First, if you don't already have the git history locally, clone it, and
173 obtain the corresponding orig.tar from the archive:
174 % git clone git.debian.org:collab-maint/foo
176 % cd foo
177 % origtargz
178 Now dump any existing patch queue:
180 % git rm -rf debian/patches
182 % git commit -m "drop existing quilt patch queue"
183 Then make new upstream tags available:
185 % git remote add -f upstream https://some.upstream/foo.git
187 Now you simply need to ensure that your git HEAD is dgit-compatible,
189 i.e., it is exactly what you would get if you ran dpkg-buildpackage
190 -i'(?:^|/)\.git(?:/|$)' -I.git -S and then unpacked the resultant
191 source package.
192 To achieve this, you might need to delete debian/source/local-options.
194 One way to have dgit check your progress is to run dgit build-source.
195 The first dgit push will require --overwrite. If this is the first
197 ever dgit push of the package, consider passing
198 --deliberately-not-fast-forward instead of --overwrite. This avoids
199 introducing a new origin commit into your git history. (This origin
200 commit would represent the most recent non-dgit upload of the package,
201 but this should already be represented in your git history.)
202
204 dgit configuration
205 We must tell dgit not to try to maintain a linear queue of patches to
206 the upstream source:
207 git config dgit.default.quilt-mode single
209 This affects only this one git tree; your other git trees for this
211 package (and co-maintainers) will need it too. Don't set it more
212 globally, because the maintainers of any other packages you work on, or
213 send patches for, may be offended by its effects.
214 unpleasant NMUs
216 debian/source/options
218 We set a source package option to help dpkg handle changes to the
219 upstream source:
220 auto-commit
222 You don't need to create this file if you are using the version 1.0
224 source package format.
225 Sample text for debian/README.source
227 It is a good idea to explain how a user can obtain a breakdown of the
228 changes to the upstream source:
229 The Debian packaging of foo is maintained in git, using the merging
231 workflow described in dgit-maint-merge(7). There isn't a patch
232 queue that can be represented as a quilt series.
233 A detailed breakdown of the changes is available from their
235 canonical representation - git commits in the packaging repository.
236 For example, to see the changes made by the Debian maintainer in
237 the first upload of upstream version 1.2.3, you could use:
238 % git clone https://git.dgit.debian.org/foo
240 % cd foo
241 % git log --oneline 1.2.3..debian/1.2.3-1 -- . ':!debian'
242 (If you have dgit, use `dgit clone foo`, rather than plain `git
244 clone`.)
245 A single combined diff, containing all the changes, follows.
247
249 Use dgit build, dgit sbuild, dgit pbuilder, dgit cowbuilder, dgit push-
250 source, and dgit push-built as detailed in dgit(1). If any command
251 fails, dgit will provide a carefully-worded error message explaining
252 what you should do. If it's not clear, file a bug against dgit.
253 Remember to pass --new for the first upload.
254 If you want to upload with git-debpush(1), for the first upload you
256 should pass the --quilt=single quilt mode option (see git-debpush(1)).
257 As another alternative to dgit build and friends, you can use a tool
259 like gitpkg(1). This works because like dgit, gitpkg(1) enforces that
260 HEAD has exactly the contents of the source package. gitpkg(1) is
261 highly configurable, and one dgit user reports using it to produce and
262 test multiple source packages, from different branches corresponding to
263 each of the current Debian suites.
264 If you want to skip dgit's checks while iterating on a problem with the
266 package build (for example, you don't want to commit your changes to
267 git), you can just run dpkg-buildpackage(1) or debuild(1) instead.
268
270 Obtaining the release
271 When upstream tags releases in git
272 % git fetch --tags upstream
274 If you want to package an untagged upstream commit (because upstream
276 does not tag releases or because you want to package an upstream
277 development snapshot), see "Using untagged upstream commits" above.
278 When upstream releases only tarballs
280 You will need the debian/gbp.conf from "When upstream releases only
282 tarballs", above. You will also need your upstream branch. Above, we
283 pushed this to salsa.debian.org. You will need to clone or fetch from
284 there, instead of relying on dgit clone/dgit fetch alone.
285 Then, either
287 % gbp import-orig ../foo_1.2.3.orig.tar.xz
289 or if you have a working watch file
291 % gbp import-orig --uscan
293 In the following, replace 1.2.3 with upstream/1.2.3.
295 Reviewing & merging the release
297 It's a good idea to preview the merge of the new upstream release.
298 First, just check for any new or deleted files that may need accounting
299 for in your copyright file:
300 % git diff --name-status --diff-filter=ADR master..1.2.3 -- . ':!debian'
302 You can then review the full merge diff:
304 % git merge-tree `git merge-base master 1.2.3` master 1.2.3 | $PAGER
306 Once you're satisfied with what will be merged, update your package:
308 % git merge 1.2.3
310 % dch -v1.2.3-1 New upstream release.
311 % git add debian/changelog && git commit -m changelog
312 If you obtained a tarball from upstream, you are ready to try a build.
314 If you merged a git tag from upstream, you will first need to generate
315 a tarball:
316 % git deborig
318
320 When upstream tags releases in git
321 We create a DFSG-clean tag to merge to master:
322 % git checkout -b pre-dfsg 1.2.3
324 % git rm evil.bin
325 % git commit -m "upstream version 1.2.3 DFSG-cleaned"
326 % git tag -s 1.2.3+dfsg
327 % git checkout master
328 % git branch -D pre-dfsg
329 Before merging the new 1.2.3+dfsg tag to master, you should first
331 determine whether it would be legally dangerous for the non-free
332 material to be publicly accessible in the git history on dgit-repos.
333 If it would be dangerous, there is a big problem; in this case please
335 consult your archive administrators (for Debian this is the dgit
336 administrator dgit-owner@debian.org and the ftpmasters
337 ftpmaster@ftp-master.debian.org).
338 When upstream releases only tarballs
340 The easiest way to handle this is to add a Files-Excluded field to
341 debian/copyright, and a uversionmangle setting in debian/watch. See
342 uscan(1). Alternatively, see the --filter option detailed in
343 gbp-import-orig(1).
344
346 The basic steps are:
347 1. Create a new branch based off upstream's master branch.
349 2. git-cherry-pick(1) commits from your master branch onto your new
351 branch.
352 3. Push the branch somewhere and ask upstream to merge it, or use
354 git-format-patch(1) or git-request-pull(1).
355 For example (and it is only an example):
357 % # fork foo.git on GitHub
359 % git remote add -f fork git@github.com:spwhitton/foo.git
360 % git checkout -b fix-error upstream/master
361 % git config branch.fix-error.pushRemote fork
362 % git cherry-pick master^2
363 % git push
364 % # submit pull request on GitHub
365 Note that when you merge an upstream release containing your forwarded
367 patches, git and dgit will transparently handle "dropping" the patches
368 that have been forwarded, "retaining" the ones that haven't.
369
371 % dgit pull
372 Alternatively, you can apply the NMU diff to your repository. The next
374 push will then require --overwrite.
375
377 dgit(1), dgit(7)
378
380 This tutorial was written and is maintained by Sean Whitton
381 <spwhitton@spwhitton.name>. It contains contributions from other dgit
382 contributors too - see the dgit copyright file.
383perl v5.36.0 Debian Project dgit-maint-merge(7)