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 When upstream releases only tarballs
113 We need a virtual upstream branch with virtual release tags.
114 gbp-import-orig(1) can manage this for us. To begin
115 % mkdir foo
117 % cd foo
118 % git init
119 Now create debian/gbp.conf:
121 [DEFAULT]
123 upstream-branch = upstream
124 debian-branch = master
125 upstream-tag = upstream/%(version)s
126 sign-tags = True
128 pristine-tar = False
129 pristine-tar-commit = False
130 [import-orig]
132 merge-mode = merge
133 merge = False
134 gbp-import-orig(1) requires a pre-existing upstream branch:
136 % git add debian/gbp.conf && git commit -m "create gbp.conf"
138 % git checkout --orphan upstream
139 % git rm -rf .
140 % git commit --allow-empty -m "initial, empty branch for upstream source"
141 % git checkout -f master
142 Then we can import the upstream version:
144 % gbp import-orig --merge --merge-mode=replace ../foo_1.2.2.orig.tar.xz
146 Our upstream branch cannot be pushed to dgit-repos, but since we will
148 need it whenever we import a new upstream version, we must push it
149 somewhere. The usual choice is salsa.debian.org:
150 % git remote add -f origin salsa.debian.org:Debian/foo.git
152 % git push --follow-tags -u origin master upstream
153 You are now ready to proceed as above, making commits to both the
155 upstream source and the debian/ directory.
156
158 This section explains how to convert an existing Debian package to this
159 workflow. It should be skipped when debianising a new package.
160 No existing git history
162 % dgit clone foo
163 % cd foo
164 % git remote add -f upstream https://some.upstream/foo.git
165 Existing git history using another workflow
167 First, if you don't already have the git history locally, clone it, and
168 obtain the corresponding orig.tar from the archive:
169 % git clone git.debian.org:collab-maint/foo
171 % cd foo
172 % origtargz
173 Now dump any existing patch queue:
175 % git rm -rf debian/patches
177 % git commit -m "drop existing quilt patch queue"
178 Then make new upstream tags available:
180 % git remote add -f upstream https://some.upstream/foo.git
182 Now you simply need to ensure that your git HEAD is dgit-compatible,
184 i.e., it is exactly what you would get if you ran dpkg-buildpackage
185 -i'(?:^|/)\.git(?:/|$)' -I.git -S and then unpacked the resultant
186 source package.
187 To achieve this, you might need to delete debian/source/local-options.
189 One way to have dgit check your progress is to run dgit build-source.
190 The first dgit push will require --overwrite. If this is the first
192 ever dgit push of the package, consider passing
193 --deliberately-not-fast-forward instead of --overwrite. This avoids
194 introducing a new origin commit into your git history. (This origin
195 commit would represent the most recent non-dgit upload of the package,
196 but this should already be represented in your git history.)
197
199 debian/source/options
200 We set some source package options such that dgit can transparently
201 handle the "dropping" and "refreshing" of changes to the upstream
202 source:
203 single-debian-patch
205 auto-commit
206 You don't need to create this file if you are using the version 1.0
208 source package format.
209 Sample text for debian/source/patch-header
211 It is a good idea to explain how a user can obtain a breakdown of the
212 changes to the upstream source:
213 The Debian packaging of foo is maintained in git, using the merging
215 workflow described in dgit-maint-merge(7). There isn't a patch
216 queue that can be represented as a quilt series.
217 A detailed breakdown of the changes is available from their
219 canonical representation - git commits in the packaging repository.
220 For example, to see the changes made by the Debian maintainer in
221 the first upload of upstream version 1.2.3, you could use:
222 % git clone https://git.dgit.debian.org/foo
224 % cd foo
225 % git log --oneline 1.2.3..debian/1.2.3-1 -- . ':!debian'
226 (If you have dgit, use `dgit clone foo`, rather than plain `git
228 clone`.)
229 A single combined diff, containing all the changes, follows.
231 If you are using the version 1.0 source package format, this text
233 should be added to README.source instead. The version 1.0 source
234 package format ignores debian/source/patch-header.
235 If you're using the version 3.0 (quilt) source package format, you
237 could add this text to README.source instead of
238 debian/source/patch-header, but this might distract from more important
239 information present in README.source.
240
242 Use dgit build, dgit sbuild, dgit pbuilder, dgit cowbuilder, dgit push-
243 source, and dgit push as detailed in dgit(1). If any command fails,
244 dgit will provide a carefully-worded error message explaining what you
245 should do. If it's not clear, file a bug against dgit. Remember to
246 pass --new for the first upload.
247 If you want to upload with git-debpush(1), for the first upload you
249 should pass the --quilt=smash quilt mode option (see git-debpush(1)).
250 As another alternative to dgit build and friends, you can use a tool
252 like gitpkg(1). This works because like dgit, gitpkg(1) enforces that
253 HEAD has exactly the contents of the source package. gitpkg(1) is
254 highly configurable, and one dgit user reports using it to produce and
255 test multiple source packages, from different branches corresponding to
256 each of the current Debian suites.
257 If you want to skip dgit's checks while iterating on a problem with the
259 package build (for example, you don't want to commit your changes to
260 git), you can just run dpkg-buildpackage(1) or debuild(1) instead.
261
263 Obtaining the release
264 When upstream tags releases in git
265 % git fetch --tags upstream
267 If you want to package an untagged upstream commit (because upstream
269 does not tag releases or because you want to package an upstream
270 development snapshot), see "Using untagged upstream commits" above.
271 When upstream releases only tarballs
273 You will need the debian/gbp.conf from "When upstream releases only
275 tarballs", above. You will also need your upstream branch. Above, we
276 pushed this to salsa.debian.org. You will need to clone or fetch from
277 there, instead of relying on dgit clone/dgit fetch alone.
278 Then, either
280 % gbp import-orig ../foo_1.2.3.orig.tar.xz
282 or if you have a working watch file
284 % gbp import-orig --uscan
286 In the following, replace 1.2.3 with upstream/1.2.3.
288 Reviewing & merging the release
290 It's a good idea to preview the merge of the new upstream release.
291 First, just check for any new or deleted files that may need accounting
292 for in your copyright file:
293 % git diff --name-status --diff-filter=ADR master..1.2.3 -- . ':!debian'
295 You can then review the full merge diff:
297 % git merge-tree `git merge-base master 1.2.3` master 1.2.3 | $PAGER
299 Once you're satisfied with what will be merged, update your package:
301 % git merge 1.2.3
303 % dch -v1.2.3-1 New upstream release.
304 % git add debian/changelog && git commit -m changelog
305 If you obtained a tarball from upstream, you are ready to try a build.
307 If you merged a git tag from upstream, you will first need to generate
308 a tarball:
309 % git deborig
311
313 When upstream tags releases in git
314 We create a DFSG-clean tag to merge to master:
315 % git checkout -b pre-dfsg 1.2.3
317 % git rm evil.bin
318 % git commit -m "upstream version 1.2.3 DFSG-cleaned"
319 % git tag -s 1.2.3+dfsg
320 % git checkout master
321 % git branch -D pre-dfsg
322 Before merging the new 1.2.3+dfsg tag to master, you should first
324 determine whether it would be legally dangerous for the non-free
325 material to be publicly accessible in the git history on dgit-repos.
326 If it would be dangerous, there is a big problem; in this case please
328 consult your archive administrators (for Debian this is the dgit
329 administrator dgit-owner@debian.org and the ftpmasters
330 ftpmaster@ftp-master.debian.org).
331 When upstream releases only tarballs
333 The easiest way to handle this is to add a Files-Excluded field to
334 debian/copyright, and a uversionmangle setting in debian/watch. See
335 uscan(1). Alternatively, see the --filter option detailed in
336 gbp-import-orig(1).
337
339 The basic steps are:
340 1. Create a new branch based off upstream's master branch.
342 2. git-cherry-pick(1) commits from your master branch onto your new
344 branch.
345 3. Push the branch somewhere and ask upstream to merge it, or use
347 git-format-patch(1) or git-request-pull(1).
348 For example (and it is only an example):
350 % # fork foo.git on GitHub
352 % git remote add -f fork git@github.com:spwhitton/foo.git
353 % git checkout -b fix-error upstream/master
354 % git config branch.fix-error.pushRemote fork
355 % git cherry-pick master^2
356 % git push
357 % # submit pull request on GitHub
358 Note that when you merge an upstream release containing your forwarded
360 patches, git and dgit will transparently handle "dropping" the patches
361 that have been forwarded, "retaining" the ones that haven't.
362
364 % dgit pull
365 Alternatively, you can apply the NMU diff to your repository. The next
367 push will then require --overwrite.
368
370 dgit(1), dgit(7)
371
373 This tutorial was written and is maintained by Sean Whitton
374 <spwhitton@spwhitton.name>. It contains contributions from other dgit
375 contributors too - see the dgit copyright file.
376perl v5.32.1 Debian Project dgit-maint-merge(7)