1 # Copyright (c) 2015, Ralf Jung <post@ralfj.de>
4 # Redistribution and use in source and binary forms, with or without
5 # modification, are permitted provided that the following conditions are met:
7 # 1. Redistributions of source code must retain the above copyright notice, this
8 # list of conditions and the following disclaimer.
9 # 2. Redistributions in binary form must reproduce the above copyright notice,
10 # this list of conditions and the following disclaimer in the documentation
11 # and/or other materials provided with the distribution.
13 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
14 # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
15 # WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
16 # DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
17 # ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
18 # (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19 # LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
20 # ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
22 # SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 #==============================================================================
24 import sys, os, os.path, subprocess
25 import configparser, itertools, re
27 import email.mime.text, email.utils, smtplib
29 mail_sender = "null@localhost"
30 config_file = os.path.join(os.path.dirname(__file__), 'git-mirror.conf')
32 def Popen_quirky(cmd, **args):
34 Runs cmd via subprocess.Popen; and if that fails, puts it into the shell (/bin/sh).
35 It seems that's what executing things in bash does, and even execve. Also,
36 all so-far released versions of Gitolite get the shebang line wrong.
39 return subprocess.Popen(cmd, **args)
41 return subprocess.Popen(['/bin/sh'] + cmd, **args)
44 def __getattr__(self, name):
45 def call(*args, capture_stderr = False, check = True):
46 '''If <capture_stderr>, return stderr merged with stdout. Otherwise, return stdout and forward stderr to our own.
47 If <check> is true, throw an exception of the process fails with non-zero exit code. Otherwise, do not.
48 In any case, return a pair of the captured output and the exit code.'''
49 cmd = ["git", name.replace('_', '-')] + list(args)
50 with subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT if capture_stderr else sys.stderr) as p:
51 (stdout, stderr) = p.communicate()
55 raise Exception("Error running {}: Non-zero exit code".format(cmd))
56 return (stdout.decode('utf-8').strip('\n'), code)
62 def git_is_forced_update(oldsha, newsha):
63 out, code = git.merge_base("--is-ancestor", oldsha, newsha, check = False) # "Check if the first <commit> is an ancestor of the second <commit>"
66 return False if code == 0 else True # if oldsha is an ancestor of newsha, then this was a "good" (non-forced) update
68 def read_config(defSection = 'DEFAULT'):
69 '''Reads a config file that may have options outside of any section.'''
70 config = configparser.ConfigParser()
71 with open(config_file) as file:
72 stream = itertools.chain(("["+defSection+"]\n",), file)
73 config.read_file(stream)
76 def send_mail(subject, text, recipients, sender, replyTo = None):
77 assert isinstance(recipients, list)
78 if not len(recipients): return # nothing to do
80 msg = email.mime.text.MIMEText(text.encode('UTF-8'), 'plain', 'UTF-8')
81 msg['Subject'] = subject
82 msg['Date'] = email.utils.formatdate(localtime=True)
84 msg['To'] = ', '.join(recipients)
85 if replyTo is not None:
86 msg['Reply-To'] = replyTo
87 # put into envelope and send
88 s = smtplib.SMTP('localhost')
89 s.sendmail(sender, recipients, msg.as_string())
93 def __init__(self, name, conf):
94 '''Creates a repository from a section of the git-mirror configuration file'''
96 self.local = conf['local']
97 self.owner = conf['owner'] # email address to notify in case of problems
98 self.hmac_secret = conf['hmac-secret'].encode('utf-8') if 'hmac-secret' in conf else None
99 self.deploy_key = conf['deploy-key'] # the SSH ky used for authenticating against remote hosts
100 self.mirrors = {} # maps mirrors to their URLs
101 mirror_prefix = 'mirror-'
102 for name in filter(lambda s: s.startswith(mirror_prefix), conf.keys()):
103 mirror = name[len(mirror_prefix):]
104 self.mirrors[mirror] = conf[name]
106 def mail_owner(self, msg):
108 send_mail("git-mirror {}".format(self.name), msg, recipients = [self.owner], sender = mail_sender)
110 def compute_hmac(self, data):
111 assert self.hmac_secret is not None
112 h = hmac.new(self.hmac_secret, digestmod = hashlib.sha1)
116 def find_mirror_by_url(self, match_urls):
117 for mirror, url in self.mirrors.items():
118 if url in match_urls:
123 '''Setup the environment to work with this repository'''
125 ssh_set_ident = os.path.join(os.path.dirname(__file__), 'ssh-set-ident.sh')
126 os.putenv('GIT_SSH', ssh_set_ident)
127 ssh_ident = os.path.join(os.path.expanduser('~/.ssh'), self.deploy_key)
128 os.putenv('GIT_MIRROR_SSH_IDENT', ssh_ident)
130 def update_mirrors(self, ref, oldsha, newsha):
131 '''Update the <ref> from <oldsha> to <newsha> on all mirrors. The update must already have happened locally.'''
132 assert len(oldsha) == 40 and len(newsha) == 40, "These are not valid SHAs."
133 source_mirror = os.getenv("GIT_MIRROR_SOURCE") # in case of a self-call via the hooks, we can skip one of the mirrors
135 # check for a forced update
136 is_forced = newsha != git_nullsha and oldsha != git_nullsha and git_is_forced_update(oldsha, newsha)
137 # tell all the mirrors
138 for mirror in self.mirrors:
139 if mirror == source_mirror:
141 sys.stdout.write("Updating mirror {}\n".format(mirror)); sys.stdout.flush()
144 # forcibly update ref remotely (someone already did a force push and hence accepted data loss)
145 git.push('--force', self.mirrors[mirror], newsha+":"+ref)
147 # nicely update ref remotely (this avoids data loss due to race conditions)
148 git.push(self.mirrors[mirror], newsha+":"+ref)
150 def update_ref_from_mirror(self, ref, oldsha, newsha, mirror, suppress_stderr = False):
151 '''Update the local version of this <ref> to what's currently on the given <mirror>. <oldsha> and <newsha> are checked. Then update all the other mirrors.'''
153 url = self.mirrors[mirror]
154 # first check whether the remote really is at newsha
155 remote_state, code = git.ls_remote(url, ref)
157 remote_sha = remote_state.split()[0]
159 remote_sha = git_nullsha
160 assert newsha == remote_sha, "Someone lied about the new SHA, which should be {}.".format(newsha)
161 # locally, we have to be at oldsha or newsha (the latter can happen if we already got this update, e.g. if it originated from us)
162 local_state, code = git.show_ref(ref, check=False)
164 local_sha = local_state.split()[0]
167 raise Exception("Something went wrong getting the local state of {}.".format(ref))
168 local_sha = git_nullsha
169 # some sanity checking, but deal gracefully with new branches appearing
170 assert local_sha in (git_nullsha, oldsha, newsha), "Someone lied about the old SHA: Local ({}) is neither old ({}) nor new ({})".format(local_sha, oldsha, newsha)
171 # if we are already at newsha locally, we also ran the local hooks, so we do not have to do anything
172 if local_sha == newsha:
173 return "Local repository is already up-to-date."
174 # update local state from local_sha to newsha.
175 if newsha != git_nullsha:
176 # We *could* now fetch the remote ref and immediately update the local one. However, then we would have to
177 # decide whether we want to allow a force-update or not. Also, the ref could already have changed remotely,
178 # so that may update to some other commit.
179 # Instead, we just fetch without updating any local ref. If the remote side changed in such a way that
180 # <newsha> is not actually fetched, that's a race and will be noticed when updating the local ref.
181 git.fetch(url, ref, capture_stderr = suppress_stderr)
182 # now update the ref, checking the old value is still local_oldsha.
183 git.update_ref(ref, newsha, 40*"0" if local_sha is None else local_sha)
185 # ref does not exist anymore. delete it.
186 assert local_sha != git_nullsha, "Why didn't we bail out earlier if there is nothing to do...?"
187 git.update_ref("-d", ref, local_sha) # this checks that the old value is still local_sha
188 # Now run the post-receive hooks. This will *also* push the changes to all mirrors, as we
189 # are one of these hooks!
190 os.putenv("GIT_MIRROR_SOURCE", mirror) # tell ourselves which repo we do *not* have to update
191 with Popen_quirky(['hooks/post-receive'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.STDOUT) as p:
192 (stdout, stderr) = p.communicate("{} {} {}\n".format(oldsha, newsha, ref).encode('utf-8'))
193 stdout = stdout.decode('utf-8')
195 raise Exception("post-receive git hook terminated with non-zero exit code {}:\n{}".format(p.returncode, stdout))
198 def find_repo_by_directory(repos, dir):
199 for (name, repo) in repos.items():
200 if dir == repo.local:
207 mail_sender = conf['DEFAULT']['mail-sender']
210 for name, section in conf.items():
211 if name != 'DEFAULT':
212 repos[name] = Repo(name, section)