dulwich/client.py

   1 # server.py -- Implementation of the server side git protocols
   2 # Copryight (C) 2008 Jelmer Vernooij <jelmer@samba.org>
   3 #
   4 # This program is free software; you can redistribute it and/or
   5 # modify it under the terms of the GNU General Public License
   6 # as published by the Free Software Foundation; version 2
   7 # of the License.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program; if not, write to the Free Software
  16 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  17 # MA  02110-1301, USA.
  18
  19 import os
  20 import select
  21 import socket
  22 import subprocess
  23 from dulwich.protocol import Protocol, TCP_GIT_PORT, extract_capabilities
  24
  25 class SimpleFetchGraphWalker(object):
  26
  27     def __init__(self, local_heads, get_parents):
  28         self.heads = set(local_heads)
  29         self.get_parents = get_parents
  30         self.parents = {}
  31
  32     def ack(self, ref):
  33         if ref in self.heads:
  34             self.heads.remove(ref)
  35         if ref in self.parents:
  36             for p in self.parents[ref]:
  37                 self.ack(p)
  38
  39     def next(self):
  40         if self.heads:
  41             ret = self.heads.pop()
  42             ps = self.get_parents(ret)
  43             self.parents[ret] = ps
  44             self.heads.update(ps)
  45             return ret
  46         return None
  47
  48
  49 class GitClient(object):
  50     """Git smart server client.
  51
  52     """
  53
  54     def __init__(self, fileno, read, write):
  55         self.proto = Protocol(read, write)
  56         self.fileno = fileno
  57
  58     def capabilities(self):
  59         return "multi_ack side-band-64k thin-pack ofs-delta"
  60
  61     def read_refs(self):
  62         server_capabilities = None
  63         refs = {}
  64         # Receive refs from server
  65         for pkt in self.proto.read_pkt_seq():
  66             (sha, ref) = pkt.rstrip("\n").split(" ", 1)
  67             if server_capabilities is None:
  68                 (ref, server_capabilities) = extract_capabilities(ref)
  69             if not (ref == "capabilities^{}" and sha == "0" * 40):
  70                 refs[ref] = sha
  71         return refs, server_capabilities
  72
  73     def send_pack(self, path):
  74         refs, server_capabilities = self.read_refs()
  75         changed_refs = [] # FIXME
  76         if not changed_refs:
  77             self.proto.write_pkt_line(None)
  78             return
  79         self.proto.write_pkt_line("%s %s %s\0%s" % (changed_refs[0][0], changed_refs[0][1], changed_refs[0][2], self.capabilities()))
  80         want = []
  81         have = []
  82         for changed_ref in changed_refs[:]:
  83             self.proto.write_pkt_line("%s %s %s" % changed_refs)
  84             want.append(changed_refs[1])
  85             if changed_refs[0] != "0"*40:
  86                 have.append(changed_refs[0])
  87         self.proto.write_pkt_line(None)
  88         # FIXME: This is implementation specific
  89         # shas = generate_pack_contents(want, have, None)
  90         # write_pack_data(self.write, shas, len(shas))
  91
  92     def fetch_pack(self, path, determine_wants, graph_walker, pack_data, progress):
  93         """Retrieve a pack from a git smart server.
  94
  95         :param determine_wants: Callback that returns list of commits to fetch
  96         :param graph_walker: Object with next() and ack().
  97         :param pack_data: Callback called for each bit of data in the pack
  98         :param progress: Callback for progress reports (strings)
  99         """
 100         (refs, server_capabilities) = self.read_refs()
 101
 102         wants = determine_wants(refs)
 103         if not wants:
 104             self.proto.write_pkt_line(None)
 105             return
 106         self.proto.write_pkt_line("want %s %s\n" % (wants[0], self.capabilities()))
 107         for want in wants[1:]:
 108             self.proto.write_pkt_line("want %s\n" % want)
 109         self.proto.write_pkt_line(None)
 110         have = graph_walker.next()
 111         while have:
 112             self.proto.write_pkt_line("have %s\n" % have)
 113             if len(select.select([self.fileno], [], [], 0)[0]) > 0:
 114                 pkt = self.proto.read_pkt_line()
 115                 parts = pkt.rstrip("\n").split(" ")
 116                 if parts[0] == "ACK":
 117                     graph_walker.ack(parts[1])
 118                     assert parts[2] == "continue"
 119             have = graph_walker.next()
 120         self.proto.write_pkt_line("done\n")
 121         pkt = self.proto.read_pkt_line()
 122         while pkt:
 123             parts = pkt.rstrip("\n").split(" ")
 124             if parts[0] == "ACK":
 125                 graph_walker.ack(pkt.split(" ")[1])
 126             if len(parts) < 3 or parts[2] != "continue":
 127                 break
 128             pkt = self.proto.read_pkt_line()
 129         for pkt in self.proto.read_pkt_seq():
 130             channel = ord(pkt[0])
 131             pkt = pkt[1:]
 132             if channel == 1:
 133                 pack_data(pkt)
 134             elif channel == 2:
 135                 progress(pkt)
 136             else:
 137                 raise AssertionError("Invalid sideband channel %d" % channel)
 138
 139
 140 class TCPGitClient(GitClient):
 141
 142     def __init__(self, host, port=TCP_GIT_PORT):
 143         self._socket = socket.socket(type=socket.SOCK_STREAM)
 144         self._socket.connect((host, port))
 145         self.rfile = self._socket.makefile('rb', -1)
 146         self.wfile = self._socket.makefile('wb', 0)
 147         self.host = host
 148         super(TCPGitClient, self).__init__(self._socket.fileno(), self.rfile.read, self.wfile.write)
 149
 150     def send_pack(self, path):
 151         self.proto.send_cmd("git-receive-pack", path, "host=%s" % self.host)
 152         super(TCPGitClient, self).send_pack(path)
 153
 154     def fetch_pack(self, path, determine_wants, graph_walker, pack_data, progress):
 155         self.proto.send_cmd("git-upload-pack", path, "host=%s" % self.host)
 156         super(TCPGitClient, self).fetch_pack(path, determine_wants, graph_walker, pack_data, progress)
 157
 158
 159 class SubprocessSocket(object):
 160     """A socket-like object that talks to an ssh subprocess via pipes."""
 161
 162     def __init__(self, proc):
 163         self.proc = proc
 164
 165     def send(self, data):
 166         return os.write(self.proc.stdin.fileno(), data)
 167
 168     def recv(self, count):
 169         return os.read(self.proc.stdout.fileno(), count)
 170
 171     def close(self):
 172         self.proc.stdin.close()
 173         self.proc.stdout.close()
 174         self.proc.wait()
 175
 176     def get_filelike_channels(self):
 177         return (self.proc.stdout, self.proc.stdin)
 178
 179
 180 class SubprocessGitClient(GitClient):
 181
 182     def __init__(self, host, port=None):
 183         self.host = host
 184         self.port = port
 185
 186     def _connect(self, service, *args):
 187         argv = [service] + list(args)
 188         proc = subprocess.Popen(argv,
 189                                 stdin=subprocess.PIPE,
 190                                 stdout=subprocess.PIPE)
 191         socket = SubprocessSocket(proc)
 192         return GitClient(proc.stdin.fileno(), socket.recv, socket.send)
 193
 194     def send_pack(self, path):
 195         client = self._connect("git-receive-pack", path)
 196         client.send_pack(path)
 197
 198     def fetch_pack(self, path, determine_wants, graph_walker, pack_data, progress):
 199         client = self._connect("git-upload-pack", path)
 200         client.fetch_pack(path, determine_wants, graph_walker, pack_data, progress)
 201