-
Notifications
You must be signed in to change notification settings - Fork 0
/
design_topgit_alternative.html
429 lines (350 loc) · 11.4 KB
/
design_topgit_alternative.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="generator" content="Docutils 0.6: http://docutils.sourceforge.net/" />
<title>Design document for a patch management system on a DVCS</title>
<meta name="author" content="Thomas Koch" />
<meta name="date" content="2010-04-02" />
<style type="text/css">
/*
:Author: David Goodger ([email protected])
:Id: $Id: html4css1.css 5951 2009-05-18 18:03:10Z milde $
:Copyright: This stylesheet has been placed in the public domain.
Default cascading style sheet for the HTML output of Docutils.
See http://docutils.sf.net/docs/howto/html-stylesheets.html for how to
customize this style sheet.
*/
/* used to remove borders from tables and images */
.borderless, table.borderless td, table.borderless th {
border: 0 }
table.borderless td, table.borderless th {
/* Override padding for "table.docutils td" with "! important".
The right padding separates the table cells. */
padding: 0 0.5em 0 0 ! important }
.first {
/* Override more specific margin styles with "! important". */
margin-top: 0 ! important }
.last, .with-subtitle {
margin-bottom: 0 ! important }
.hidden {
display: none }
a.toc-backref {
text-decoration: none ;
color: black }
blockquote.epigraph {
margin: 2em 5em ; }
dl.docutils dd {
margin-bottom: 0.5em }
/* Uncomment (and remove this text!) to get bold-faced definition list terms
dl.docutils dt {
font-weight: bold }
*/
div.abstract {
margin: 2em 5em }
div.abstract p.topic-title {
font-weight: bold ;
text-align: center }
div.admonition, div.attention, div.caution, div.danger, div.error,
div.hint, div.important, div.note, div.tip, div.warning {
margin: 2em ;
border: medium outset ;
padding: 1em }
div.admonition p.admonition-title, div.hint p.admonition-title,
div.important p.admonition-title, div.note p.admonition-title,
div.tip p.admonition-title {
font-weight: bold ;
font-family: sans-serif }
div.attention p.admonition-title, div.caution p.admonition-title,
div.danger p.admonition-title, div.error p.admonition-title,
div.warning p.admonition-title {
color: red ;
font-weight: bold ;
font-family: sans-serif }
/* Uncomment (and remove this text!) to get reduced vertical space in
compound paragraphs.
div.compound .compound-first, div.compound .compound-middle {
margin-bottom: 0.5em }
div.compound .compound-last, div.compound .compound-middle {
margin-top: 0.5em }
*/
div.dedication {
margin: 2em 5em ;
text-align: center ;
font-style: italic }
div.dedication p.topic-title {
font-weight: bold ;
font-style: normal }
div.figure {
margin-left: 2em ;
margin-right: 2em }
div.footer, div.header {
clear: both;
font-size: smaller }
div.line-block {
display: block ;
margin-top: 1em ;
margin-bottom: 1em }
div.line-block div.line-block {
margin-top: 0 ;
margin-bottom: 0 ;
margin-left: 1.5em }
div.sidebar {
margin: 0 0 0.5em 1em ;
border: medium outset ;
padding: 1em ;
background-color: #ffffee ;
width: 40% ;
float: right ;
clear: right }
div.sidebar p.rubric {
font-family: sans-serif ;
font-size: medium }
div.system-messages {
margin: 5em }
div.system-messages h1 {
color: red }
div.system-message {
border: medium outset ;
padding: 1em }
div.system-message p.system-message-title {
color: red ;
font-weight: bold }
div.topic {
margin: 2em }
h1.section-subtitle, h2.section-subtitle, h3.section-subtitle,
h4.section-subtitle, h5.section-subtitle, h6.section-subtitle {
margin-top: 0.4em }
h1.title {
text-align: center }
h2.subtitle {
text-align: center }
hr.docutils {
width: 75% }
img.align-left, .figure.align-left{
clear: left ;
float: left ;
margin-right: 1em }
img.align-right, .figure.align-right {
clear: right ;
float: right ;
margin-left: 1em }
.align-left {
text-align: left }
.align-center {
clear: both ;
text-align: center }
.align-right {
text-align: right }
/* reset inner alignment in figures */
div.align-right {
text-align: left }
/* div.align-center * { */
/* text-align: left } */
ol.simple, ul.simple {
margin-bottom: 1em }
ol.arabic {
list-style: decimal }
ol.loweralpha {
list-style: lower-alpha }
ol.upperalpha {
list-style: upper-alpha }
ol.lowerroman {
list-style: lower-roman }
ol.upperroman {
list-style: upper-roman }
p.attribution {
text-align: right ;
margin-left: 50% }
p.caption {
font-style: italic }
p.credits {
font-style: italic ;
font-size: smaller }
p.label {
white-space: nowrap }
p.rubric {
font-weight: bold ;
font-size: larger ;
color: maroon ;
text-align: center }
p.sidebar-title {
font-family: sans-serif ;
font-weight: bold ;
font-size: larger }
p.sidebar-subtitle {
font-family: sans-serif ;
font-weight: bold }
p.topic-title {
font-weight: bold }
pre.address {
margin-bottom: 0 ;
margin-top: 0 ;
font: inherit }
pre.literal-block, pre.doctest-block {
margin-left: 2em ;
margin-right: 2em }
span.classifier {
font-family: sans-serif ;
font-style: oblique }
span.classifier-delimiter {
font-family: sans-serif ;
font-weight: bold }
span.interpreted {
font-family: sans-serif }
span.option {
white-space: nowrap }
span.pre {
white-space: pre }
span.problematic {
color: red }
span.section-subtitle {
/* font-size relative to parent (h1..h6 element) */
font-size: 80% }
table.citation {
border-left: solid 1px gray;
margin-left: 1px }
table.docinfo {
margin: 2em 4em }
table.docutils {
margin-top: 0.5em ;
margin-bottom: 0.5em }
table.footnote {
border-left: solid 1px black;
margin-left: 1px }
table.docutils td, table.docutils th,
table.docinfo td, table.docinfo th {
padding-left: 0.5em ;
padding-right: 0.5em ;
vertical-align: top }
table.docutils th.field-name, table.docinfo th.docinfo-name {
font-weight: bold ;
text-align: left ;
white-space: nowrap ;
padding-left: 0 }
h1 tt.docutils, h2 tt.docutils, h3 tt.docutils,
h4 tt.docutils, h5 tt.docutils, h6 tt.docutils {
font-size: 100% }
ul.auto-toc {
list-style-type: none }
</style>
</head>
<body>
<div class="document" id="design-document-for-a-patch-management-system-on-a-dvcs">
<h1 class="title">Design document for a patch management system on a DVCS</h1>
<table class="docinfo" frame="void" rules="none">
<col class="docinfo-name" />
<col class="docinfo-content" />
<tbody valign="top">
<tr><th class="docinfo-name">Author:</th>
<td>Thomas Koch</td></tr>
<tr><th class="docinfo-name">Date:</th>
<td>2010-04-02</td></tr>
</tbody>
</table>
<!-- This file is written in the ReST format:
http://docutils.sourceforge.net/rst.html -->
<div class="section" id="requirements">
<h1>Requirements</h1>
<p>The system to implement manages patchsets. A patchset is a set of patches with
a tree-ish dependency graph between the patches. There's one distinct root of
this dependency graph.</p>
<p>Patches are managed as branches with each branch representing a patch.
Modification of a patch is done by a commit to the respective branch. A branch
representing a patch as part of a patchset is called patchbranch.</p>
<p>The patch of a patchbranch is created as the diff between the root of the
patchbranch and the head.</p>
<p>The most important management methods are:</p>
<ul class="simple">
<li>Export a patchset in different formats<ul>
<li>quilt</li>
<li>a merged commit of all patches</li>
<li>a line of commits with each commit representing one patch</li>
</ul>
</li>
<li>Update a patchset against an updated root.</li>
<li>Copy a patchset</li>
<li>Delete a patchset from direct visibility while preserving all history about
it</li>
<li>Hide and unhide a patchset from direct visibility</li>
</ul>
<p>Additional requirements:</p>
<ul class="simple">
<li>The system should be implementable on top of GIT, Mercurial and eventually
Bazaar.</li>
<li>The system must easily cope with multiple different and independent patchsets.</li>
<li>All information about a patchset must be encoded in one distinct branch.
Publishing this one branch must be sufficient to allow somebody else to
recreate the patchset with all of its patchbranches.</li>
<li>The system should not rely on the presence of hooks.</li>
<li>The system should not require the addition of management files in patch
branches (like .topmsg and .topdeps in topgit)</li>
<li>The system must be easy to understand for a regular user of the underlying
DVCS.</li>
<li>The implementation may allow a patchset to depend on another patchset(s).</li>
</ul>
</div>
<div class="section" id="implementation">
<h1>implementation</h1>
<div class="section" id="patchset-meta-branch">
<h2>patchset meta branch</h2>
<p>A patchset meta branch holds all informations about one patchset. First, it
holds references to the top commits of all patch branches in the form of parent
references of commits. Thus pushing the patchset meta branch automatically also
pushes all commits of all patch branches.</p>
<p>Secondly, the patchset meta branch contains meta informations about the
patchset. These meta informations are:</p>
<ul class="simple">
<li>The names of all patch branches together with the most recent commit
identifier of a particular patch branch. Let's save this information in a
file called branches.</li>
<li>A message for each patch branch that explains the patch. These messages can
be saved in the file tree as msg/${PATCH-BRANCH-NAME}</li>
<li>References to the dependencies of the patch (other patches of the same
patchset or the root of the patchset). This is also encoded in the file
branches.</li>
</ul>
<p>Since the patchset meta branch holds all this informations, it is possible, to
delete all patch branches and recreate them from this informations.</p>
<p>Although the commits of the patchset meta branches hold references to the patch
branches, its file tree does not need to contain any files from the referenced
patches. This may confuse the underlying DVCS, but the patch meta branch is not
ment to be directly inspected.</p>
</div>
<div class="section" id="the-branches-file">
<h2>The branches file</h2>
<p>A branches file for a fictive patchset could look like:</p>
<pre class="literal-block">
# patch branches without an explicit dependency depend on the root of the
# patchset tree
# A Root can be given as either a fix commit (seen here), a branch or a tag.
# A fixed commit or tag is useful to maintain a patchset against an older
# upstream version
ROOT: 6a8589de32d490806ab86432a3181370e65953ca
# A tag as a dependency
#ROOT: upstream/0.1.2
# A branch as a dependency
#ROOT: upstream
# A regular patch with it's name and last commit
BRANCH: debian/use-debian-jars-in-build-xml 4bab542c261ff1a1ae87151c3536f19ef02d7937
# two other regular patches
BRANCH: upstream-jira/HDFS-1234 a8e4af13106582ca1bfbbcaeb0537f73faf46d87
BRANCH: upstream-jira/MAP-REDUCE-007 e3426bcbcb2537478f851edcf6eb04b34f6c7106
# This patch depends on the above two patches
# The sha1 below the dependency patches references a merge commit of the two
# dependencies
BRANCH: upstream-jira/HDFS-008 517851aa829d77e09bc5e59985fed1b0aa339cc6
DEPENDENCIES:
upstream-jira/HDFS-1234
upstream-jira/MAP-REDUCE-007
cc294f2e4773c4ff71efb83648a0e16835fca841
# A patch branch that belongs to the patch branch, but won't get exported (yet)
BRANCH: upstream-jira/HDFS-9999 74257905azgsa4689bc5e59985fed1b0aa339cc6
BRANCH-FLAGS: noexport
</pre>
</div>
</div>
</div>
</body>
</html>