dulwich.server: Add serve_command.

NEWS

@@ -8,6 +8,9 @@
 
   * Add write_tree_diff(). (Jelmer Vernooij)
 
+  * Add `serve_command` function for git server commands as executables.
+    (Jelmer Vernooij)
+
  BUG FIXES
 
   * Correct short-circuiting operation for no-op fetches in the server.

dulwich/server.py

@@ -48,8 +48,10 @@ from dulwich.pack import (
     write_pack_data,
     )
 from dulwich.protocol import (
+    BufferedPktLineWriter,
     MULTI_ACK,
     MULTI_ACK_DETAILED,
+    Protocol,
     ProtocolFile,
     ReceivableProtocol,
     SINGLE_ACK,
@@ -58,7 +60,6 @@ from dulwich.protocol import (
     ack_type,
     extract_capabilities,
     extract_want_line_capabilities,
-    BufferedPktLineWriter,
     )
 from dulwich.repo import (
     Repo,
@@ -783,3 +784,28 @@ def main(argv=sys.argv):
     backend = DictBackend({'/': Repo(gitdir)})
     server = TCPGitServer(backend, 'localhost')
     server.serve_forever()
+
+
+def serve_command(handler_cls, argv=sys.argv, backend=None, inf=sys.stdin,
+                  outf=sys.stdout):
+    """Serve a single command.
+
+    This is mostly useful for the implementation of commands used by e.g. git+ssh.
+
+    :param handler_cls: `Handler` class to use for the request
+    :param argv: execv-style command-line arguments. Defaults to sys.argv.
+    :param backend: `Backend` to use
+    :param inf: File-like object to read from, defaults to standard input.
+    :param outf: File-like object to write to, defaults to standard output.
+    :return: Exit code for use with sys.exit. 0 on success, 1 on failure.
+    """
+    if backend is None:
+        backend = FileSystemBackend()
+    def send_fn(data):
+        outf.write(data)
+        outf.flush()
+    proto = Protocol(inf.read, send_fn)
+    handler = handler_cls(backend, argv[1:], proto)
+    # FIXME: Catch exceptions and write a single-line summary to outf.
+    handler.handle()
+    return 0

dulwich/tests/test_server.py

@@ -18,6 +18,7 @@
 
 """Tests for the smart protocol server."""
 
+from cStringIO import StringIO
 import os
 import tempfile
 
@@ -38,7 +39,9 @@ from dulwich.server import (
     MultiAckGraphWalkerImpl,
     MultiAckDetailedGraphWalkerImpl,
     _split_proto_line,
+    serve_command,
     ProtocolGraphWalker,
+    ReceivePackHandler,
     SingleAckGraphWalkerImpl,
     UploadPackHandler,
     )
@@ -665,3 +668,28 @@ class FileSystemBackendTests(TestCase):
     def test_child(self):
         self.assertRaises(NotGitRepository,
             self.backend.open_repository, os.path.join(self.path, "foo"))
+
+
+class ServeCommandTests(TestCase):
+    """Tests for serve_command."""
+
+    def setUp(self):
+        super(ServeCommandTests, self).setUp()
+        self.backend = DictBackend({})
+
+    def serve_command(self, handler_cls, args, inf, outf):
+        return serve_command(handler_cls, ["test"] + args, backend=self.backend,
+            inf=inf, outf=outf)
+
+    def test_receive_pack(self):
+        commit = make_commit(id=ONE, parents=[], commit_time=111)
+        self.backend.repos["/"] = MemoryRepo.init_bare(
+            [commit], {"refs/heads/master": commit.id})
+        outf = StringIO()
+        exitcode = self.serve_command(ReceivePackHandler, ["/"], StringIO("0000"), outf)
+        outlines = outf.getvalue().splitlines()
+        self.assertEquals(2, len(outlines))
+        self.assertEquals("1111111111111111111111111111111111111111 refs/heads/master",
+            outlines[0][4:].split("\x00")[0])
+        self.assertEquals("0000", outlines[-1])
+        self.assertEquals(0, exitcode)