Documentation: HTTP needs update-server-info.
[git/git.git] / Documentation / everyday.txt
1 Everyday GIT With 20 Commands Or So
2 ===================================
3
4 GIT suite has over 100 commands, and the manual page for each of
5 them discusses what the command does and how it is used in
6 detail, but until you know what command should be used in order
7 to achieve what you want to do, you cannot tell which manual
8 page to look at, and if you know that already you do not need
9 the manual.
10
11 Does that mean you need to know all of them before you can use
12 git? Not at all. Depending on the role you play, the set of
13 commands you need to know is slightly different, but in any case
14 what you need to learn is far smaller than the full set of
15 commands to carry out your day-to-day work. This document is to
16 serve as a cheat-sheet and a set of pointers for people playing
17 various roles.
18
19 <<Basic Repository>> commands are needed by people who has a
20 repository --- that is everybody, because every working tree of
21 git is a repository.
22
23 In addition, <<Individual Developer (Standalone)>> commands are
24 essential for anybody who makes a commit, even for somebody who
25 works alone.
26
27 If you work with other people, you will need commands listed in
28 <<Individual Developer (Participant)>> section as well.
29
30 People who play <<Integrator>> role need to learn some more
31 commands in addition to the above.
32
33 <<Repository Administration>> commands are for system
34 administrators who are responsible to care and feed git
35 repositories to support developers.
36
37
38 Basic Repository[[Basic Repository]]
39 ------------------------------------
40
41 Everybody uses these commands to feed and care git repositories.
42
43 * gitlink:git-init-db[1] or gitlink:git-clone[1] to create a
44 new repository.
45
46 * gitlink:git-fsck-objects[1] to validate the repository.
47
48 * gitlink:git-prune[1] to garbage collect crufts in the
49 repository.
50
51 * gitlink:git-repack[1] to pack loose objects for efficiency.
52
53 Examples
54 ~~~~~~~~
55
56 Check health and remove cruft.::
57 +
58 ------------
59 $ git fsck-objects <1>
60 $ git prune
61 $ git count-objects <2>
62 $ git repack <3>
63 $ git prune <4>
64
65 <1> running without "--full" is usually cheap and assures the
66 repository health reasonably well.
67 <2> check how many loose objects there are and how much
68 diskspace is wasted by not repacking.
69 <3> without "-a" repacks incrementally. repacking every 4-5MB
70 of loose objects accumulation may be a good rule of thumb.
71 <4> after repack, prune removes the duplicate loose objects.
72 ------------
73
74 Repack a small project into single pack.::
75 +
76 ------------
77 $ git repack -a -d <1>
78 $ git prune
79
80 <1> pack all the objects reachable from the refs into one pack
81 and remove unneeded other packs
82 ------------
83
84
85 Individual Developer (Standalone)[[Individual Developer (Standalone)]]
86 ----------------------------------------------------------------------
87
88 A standalone individual developer does not exchange patches with
89 other poeple, and works alone in a single repository, using the
90 following commands.
91
92 * gitlink:git-show-branch[1] to see where you are.
93
94 * gitlink:git-log[1] to see what happened.
95
96 * gitlink:git-whatchanged[1] to find out where things have
97 come from.
98
99 * gitlink:git-checkout[1] and gitlink:git-branch[1] to switch
100 branches.
101
102 * gitlink:git-add[1] and gitlink:git-update-index[1] to manage
103 the index file.
104
105 * gitlink:git-diff[1] and gitlink:git-status[1] to see what
106 you are in the middle of doing.
107
108 * gitlink:git-commit[1] to advance the current branch.
109
110 * gitlink:git-reset[1] and gitlink:git-checkout[1] (with
111 pathname parameters) to undo changes.
112
113 * gitlink:git-pull[1] with "." as the remote to merge between
114 local branches.
115
116 * gitlink:git-rebase[1] to maintain topic branches.
117
118 * gitlink:git-tag[1] to mark known point.
119
120 Examples
121 ~~~~~~~~
122
123 Extract a tarball and create a working tree and a new repository to keep track of it.::
124 +
125 ------------
126 $ tar zxf frotz.tar.gz
127 $ cd frotz
128 $ git-init-db
129 $ git add . <1>
130 $ git commit -m 'import of frotz source tree.'
131 $ git tag v2.43 <2>
132
133 <1> add everything under the current directory.
134 <2> make a lightweight, unannotated tag.
135 ------------
136
137 Create a topic branch and develop.::
138 +
139 ------------
140 $ git checkout -b alsa-audio <1>
141 $ edit/compile/test
142 $ git checkout -- curses/ux_audio_oss.c <2>
143 $ git add curses/ux_audio_alsa.c <3>
144 $ edit/compile/test
145 $ git diff <4>
146 $ git commit -a -s <5>
147 $ edit/compile/test
148 $ git reset --soft HEAD^ <6>
149 $ edit/compile/test
150 $ git diff ORIG_HEAD <7>
151 $ git commit -a -c ORIG_HEAD <8>
152 $ git checkout master <9>
153 $ git pull . alsa-audio <10>
154 $ git log --since='3 days ago' <11>
155 $ git log v2.43.. curses/ <12>
156
157 <1> create a new topic branch.
158 <2> revert your botched changes in "curses/ux_audio_oss.c".
159 <3> you need to tell git if you added a new file; removal and
160 modification will be caught if you do "commit -a" later.
161 <4> to see what changes you are committing.
162 <5> commit everything as you have tested, with your sign-off.
163 <6> take the last commit back, keeping what is in the working tree.
164 <7> look at the changes since the premature commit we took back.
165 <8> redo the commit undone in the previous step, using the message
166 you originally wrote.
167 <9> switch to the master branch.
168 <10> merge a topic branch into your master branch
169 <11> review commit logs; other forms to limit output can be
170 combined and include --max-count=10 (show 10 commits), --until='2005-12-10'.
171 <12> view only the changes that touch what's in curses/
172 directory, since v2.43 tag.
173 ------------
174
175
176 Individual Developer (Participant)[[Individual Developer (Participant)]]
177 ------------------------------------------------------------------------
178
179 A developer working as a participant in a group project needs to
180 learn how to communicate with others, and uses these commands in
181 addition to the ones needed by a standalone developer.
182
183 * gitlink:git-clone[1] from the upstream to prime your local
184 repository.
185
186 * gitlink:git-pull[1] and gitlink:git-fetch[1] from "origin"
187 to keep up-to-date with the upstream.
188
189 * gitlink:git-push[1] to shared repository, if you adopt CVS
190 style shared repository workflow.
191
192 * gitlink:git-format-patch[1] to prepare e-mail submission, if
193 you adopt Linux kernel-style public forum workflow.
194
195 Examples
196 ~~~~~~~~
197
198 Clone the upstream and work on it. Feed changes to upstream.::
199 +
200 ------------
201 $ git clone git://git.kernel.org/pub/scm/.../torvalds/linux-2.6 my2.6
202 $ cd my2.6
203 $ edit/compile/test; git commit -a -s <1>
204 $ git format-patch origin <2>
205 $ git pull <3>
206 $ git whatchanged -p ORIG_HEAD.. arch/i386 include/asm-i386 <4>
207 $ git pull git://git.kernel.org/pub/.../jgarzik/libata-dev.git ALL <5>
208 $ git reset --hard ORIG_HEAD <6>
209 $ git prune <7>
210 $ git fetch --tags <8>
211
212 <1> repeat as needed.
213 <2> extract patches from your branch for e-mail submission.
214 <3> "pull" fetches from "origin" by default and merges.
215 <4> look at the changes since last time we checked, only in the
216 area we are interested in.
217 <5> fetch from a specific branch from a specific repository and and merge.
218 <6> revert the pull.
219 <7> garbage collect leftover objects from reverted pull.
220 <8> from time to time, obtain official tags from the "origin"
221 and store them under .git/refs/tags/.
222 ------------
223
224
225 Push into another repository.::
226 +
227 ------------
228 satellite$ git clone mothership:frotz/.git frotz <1>
229 satellite$ cd frotz
230 satellite$ cat .git/remotes/origin <2>
231 URL: mothership:frotz/.git
232 Pull: master:origin
233 satellite$ echo 'Push: master:satellite' >>.git/remotes/origin <3>
234 satellite$ edit/compile/test/commit
235 satellite$ git push origin <4>
236
237 mothership$ cd frotz
238 mothership$ git checkout master
239 mothership$ git pull . satellite <5>
240
241 <1> mothership machine has a frotz repository under your home
242 directory; clone from it to start a repository on the satellite
243 machine.
244 <2> clone creates this file by default. It arranges "git pull"
245 to fetch and store the master branch head of mothership machine
246 to local "origin" branch.
247 <3> arrange "git push" to push local "master" branch to
248 "satellite" branch of the mothership machine.
249 <4> push will stash our work away on "satellite" branch on the
250 mothership machine. You could use this as a back-up method.
251 <5> on mothership machine, merge the work done on the satellite
252 machine into the master branch.
253 ------------
254
255 Branch off of a specific tag.::
256 +
257 ------------
258 $ git checkout -b private2.6.14 v2.6.14 <1>
259 $ edit/compile/test; git commit -a
260 $ git checkout master
261 $ git format-patch -k -m --stdout v2.6.14..private2.6.14 |
262 git am -3 -k <2>
263
264 <1> create a private branch based on a well known (but somewhat behind)
265 tag.
266 <2> forward port all changes in private2.6.14 branch to master branch
267 without a formal "merging".
268 ------------
269
270
271 Integrator[[Integrator]]
272 ------------------------
273
274 A fairly central person acting as the integrator in a group
275 project receives changes made by others, reviews and integrates
276 them and publishes the result for others to use, using these
277 commands in addition to the ones needed by participants.
278
279 * gitlink:git-am[1] to apply patches e-mailed in from your
280 contributors.
281
282 * gitlink:git-pull[1] to merge from your trusted lieutenants.
283
284 * gitlink:git-format-patch[1] to prepare and send suggested
285 alternative to contributors.
286
287 * gitlink:git-revert[1] to undo botched commits.
288
289 * gitlink:git-push[1] to publish the bleeding edge.
290
291
292 Examples
293 ~~~~~~~~
294
295 My typical GIT day.::
296 +
297 ------------
298 $ git status <1>
299 $ git show-branch <2>
300 $ mailx <3>
301 & s 2 3 4 5 ./+to-apply
302 & s 7 8 ./+hold-linus
303 & q
304 $ git checkout master
305 $ git am -3 -i -s -u ./+to-apply <4>
306 $ compile/test
307 $ git checkout -b hold/linus && git am -3 -i -s -u ./+hold-linus <5>
308 $ git checkout topic/one && git rebase master <6>
309 $ git checkout pu && git reset --hard master <7>
310 $ git pull . topic/one topic/two && git pull . hold/linus <8>
311 $ git checkout maint
312 $ git cherry-pick master~4 <9>
313 $ compile/test
314 $ git tag -s -m 'GIT 0.99.9x' v0.99.9x <10>
315 $ git fetch ko && git show-branch master maint 'tags/ko-*' <11>
316 $ git push ko <12>
317 $ git push ko v0.99.9x <13>
318
319 <1> see what I was in the middle of doing, if any.
320 <2> see what topic branches I have and think about how ready
321 they are.
322 <3> read mails, save ones that are applicable, and save others
323 that are not quite ready.
324 <4> apply them, interactively, with my sign-offs.
325 <5> create topic branch as needed and apply, again with my
326 sign-offs.
327 <6> rebase internal topic branch that has not been merged to the
328 master, nor exposed as a part of a stable branch.
329 <7> restart "pu" every time from the master.
330 <8> and bundle topic branches still cooking.
331 <9> backport a critical fix.
332 <10> create a signed tag.
333 <11> make sure I did not accidentally rewound master beyond what I
334 already pushed out. "ko" shorthand points at the repository I have
335 at kernel.org, and looks like this:
336 $ cat .git/remotes/ko
337 URL: kernel.org:/pub/scm/git/git.git
338 Pull: master:refs/tags/ko-master
339 Pull: maint:refs/tags/ko-maint
340 Push: master
341 Push: +pu
342 Push: maint
343 <12> push out the bleeding edge.
344 <13> push the tag out, too.
345 ------------
346
347
348 Repository Administration[[Repository Administration]]
349 ------------------------------------------------------
350
351 A repository administrator uses the following tools to set up
352 and maintain access to the repository by developers.
353
354 * gitlink:git-daemon[1] to allow anonymous download from
355 repository.
356
357 * gitlink:git-shell[1] can be used as a 'restricted login shell'
358 for shared central repository users.
359
360 * link:howto/update-hook-example.txt[update hook howto] has a
361 good example of managing a shared central repository.
362
363
364 Examples
365 ~~~~~~~~
366
367 Run git-daemon to serve /pub/scm from inetd.::
368 +
369 ------------
370 $ grep git /etc/inet.conf
371 git stream tcp nowait nobody \
372 /usr/bin/git-daemon git-daemon --inetd --syslog --export-all /pub/scm
373 ------------
374 +
375 The actual configuration line should be on one line.
376
377 Give push/pull only access to developers.::
378 +
379 ------------
380 $ grep git /etc/passwd <1>
381 alice:x:1000:1000::/home/alice:/usr/bin/git-shell
382 bob:x:1001:1001::/home/bob:/usr/bin/git-shell
383 cindy:x:1002:1002::/home/cindy:/usr/bin/git-shell
384 david:x:1003:1003::/home/david:/usr/bin/git-shell
385 $ grep git /etc/shells <2>
386 /usr/bin/git-shell
387
388 <1> log-in shell is set to /usr/bin/git-shell, which does not
389 allow anything but "git push" and "git pull". The users should
390 get an ssh access to the machine.
391 <2> in many distributions /etc/shells needs to list what is used
392 as the login shell.
393 ------------
394
395 CVS-style shared repository.::
396 +
397 ------------
398 $ grep git /etc/group <1>
399 git:x:9418:alice,bob,cindy,david
400 $ cd /home/devo.git
401 $ ls -l <2>
402 lrwxrwxrwx 1 david git 17 Dec 4 22:40 HEAD -> refs/heads/master
403 drwxrwsr-x 2 david git 4096 Dec 4 22:40 branches
404 -rw-rw-r-- 1 david git 84 Dec 4 22:40 config
405 -rw-rw-r-- 1 david git 58 Dec 4 22:40 description
406 drwxrwsr-x 2 david git 4096 Dec 4 22:40 hooks
407 -rw-rw-r-- 1 david git 37504 Dec 4 22:40 index
408 drwxrwsr-x 2 david git 4096 Dec 4 22:40 info
409 drwxrwsr-x 4 david git 4096 Dec 4 22:40 objects
410 drwxrwsr-x 4 david git 4096 Nov 7 14:58 refs
411 drwxrwsr-x 2 david git 4096 Dec 4 22:40 remotes
412 $ ls -l hooks/update <3>
413 -r-xr-xr-x 1 david git 3536 Dec 4 22:40 update
414 $ cat info/allowed-users <4>
415 refs/heads/master alice\|cindy
416 refs/heads/doc-update bob
417 refs/tags/v[0-9]* david
418
419 <1> place the developers into the same git group.
420 <2> and make the shared repository writable by the group.
421 <3> use update-hook example by Carl from Documentation/howto/
422 for branch policy control.
423 <4> alice and cindy can push into master, only bob can push into doc-update.
424 david is the release manager and is the only person who can
425 create and push version tags.
426 ------------
427
428 HTTP server to support dumb protocol transfer.::
429 +
430 ------------
431 dev$ git update-server-info <1>
432 dev$ ftp user@isp.example.com <2>
433 ftp> cp -r .git /home/user/myproject.git
434
435 <1> make sure your info/refs and objects/info/packs are up-to-date
436 <2> upload to public HTTP server hosted by your ISP.
437 ------------