fix: mock server refusing connections

pactman/mock/mock_server.py

@@ -2,7 +2,7 @@
 import queue
 import traceback
 from http.server import BaseHTTPRequestHandler, HTTPServer
-from multiprocessing import Process, Queue
+from multiprocessing import Process, Queue, SimpleQueue
 
 from .pact_request_handler import PactRequestHandler
 
@@ -23,8 +23,10 @@ def __init__(self, pact):
         self.pact = pact
         self.interactions = Queue()
         self.results = Queue()
-        self.process = Process(target=run_server, args=(pact, self.interactions, self.results))
+        notify_start = SimpleQueue()
+        self.process = Process(target=run_server, args=(pact, self.interactions, self.results, notify_start))
         self.process.start()
+        notify_start.get()
 
     def setup(self, interactions):
         for interaction in interactions:
@@ -42,16 +44,17 @@ def terminate(self):
         self.process.terminate()
 
 
-def run_server(pact, interactions, results):
-    httpd = MockServer(pact, interactions, results)
+def run_server(pact, interactions, results, notify_start):
+    httpd = MockServer(pact, interactions, results, notify_start)
     httpd.serve_forever()
 
 
 class MockServer(HTTPServer):
-    def __init__(self, pact, interactions, results):
+    def __init__(self, pact, interactions, results, notify_start):
         self.pact = pact
         self.incoming_interactions = interactions
         self.outgoing_results = results
+        self.notify_start = notify_start
         server_address = ("", pact.port)
         super().__init__(server_address, MockHTTPRequestHandler)
         self.interactions = []
@@ -60,6 +63,11 @@ def __init__(self, pact, interactions, results):
         self.log.setLevel(logging.DEBUG)
         self.log.propagate = False
 
+    def server_activate(self):
+        super().server_activate()
+        self.notify_start.put(True)
+        del self.notify_start
+
     class Error(Exception):
         pass
 

pactman/test/test_mock_server.py

@@ -1,3 +1,4 @@
+import socket
 from queue import Queue
 from unittest.mock import Mock
 
@@ -21,8 +22,43 @@ def queue(*a):
 )
 def test_correct_result_assertion(mocker, results, exception):
     mocker.patch("pactman.mock.mock_server.Process", autospec=True)
+    mocker.patch("pactman.mock.mock_server.SimpleQueue", autospec=True)
     s = mock_server.Server(Mock())
     s.results = results
     with pytest.raises(exception) as e:
         s.verify()
     assert "spam" in str(e.value)
+
+
+@pytest.fixture
+def unused_port():
+    with socket.socket() as s:
+        s.bind(("localhost", 0))
+        _, port = s.getsockname()[:2]
+        return port
+
+
+@pytest.fixture
+def a_mock_server(tmpdir, unused_port):
+    from pactman import Consumer, Provider
+
+    pact = Consumer("consumer").has_pact_with(
+        Provider("provider"),
+        pact_dir=str(tmpdir),
+        log_dir=str(tmpdir),
+        host_name="localhost",
+        port=unused_port,
+    )
+
+    server = mock_server.Server(pact)
+    yield server
+    server.terminate()
+
+
+def test_mockserver_is_connectable(a_mock_server):
+
+    pact = a_mock_server.pact
+    with socket.socket() as s:
+        # Will fail with ConnectionRefusedError if the server is not already
+        # bound and listening
+        s.connect((pact.host_name, pact.port))