Properly acquire local port after calculating it.

README.md

@@ -704,12 +704,14 @@ Selector supports below parameters. Refer to [UiSelector java doc](http://develo
 - Qian Jin ([@QianJin2013][])
 - Xu Jingjie ([@xiscoxu][])
 - Xia Mingyuan ([@mingyuan-xia][])
+- Artem Iglikov, Google Inc. ([@artikz][])
 
 [@xiaocong]: https://github.com/xiaocong
 [@yuanyuan]: https://github.com/yuanyuanzou
 [@QianJin2013]: https://github.com/QianJin2013
 [@xiscoxu]: https://github.com/xiscoxu
 [@mingyuan-xia]: https://github.com/mingyuan-xia
+[@artikz]: https://github.com/artikz
 
 ## Issues & Discussion
 

test/test_multi_process.py

@@ -0,0 +1,66 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+import unittest
+import logging
+import mock
+import os
+import subprocess
+import uiautomator
+import multiprocessing
+
+
+def _create_next_local_port_stub(ports):
+  def _next_local_port_stub(_):
+    max_used_port = max(x[1] for x in ports) if ports else 0
+    return max(max_used_port, uiautomator.LOCAL_PORT) + 1
+  return _next_local_port_stub
+
+
+def _create_adb_forward_stub(serial, ports):
+  def _adb_forward_stub(local_port, device_port, rebind=True):
+    ports.append([serial, local_port, device_port])
+  return _adb_forward_stub
+
+
+def _create_adb_forward_list_stub(ports):
+  def _adb_forward_list_stub():
+    return [[x[0], "tcp:" + str(x[1]), "tcp:" + str(x[2])] for x in ports]
+  return _adb_forward_list_stub
+
+
+class TestMultiProcess(unittest.TestCase):
+
+  def setUp(self):
+    self.ports = []
+
+  def create_device(self, serial):
+      device = uiautomator.Device(serial=serial)
+      device.server.adb = mock.MagicMock()
+      device.server.adb.device_serial = lambda: serial
+      device.server.adb.forward = _create_adb_forward_stub(serial, self.ports)
+      device.server.adb.forward_list = _create_adb_forward_list_stub(self.ports)
+      device.server.ping = mock.MagicMock(return_value="pong")
+      return device
+
+  def test_run_sequential(self):
+      uiautomator.next_local_port = _create_next_local_port_stub(self.ports)
+
+      device1 = self.create_device("1")
+      device1.server.start()
+
+      device2 = self.create_device("2")
+      device2.server.start()
+
+      self.assertNotEqual(device1.server.local_port, device2.server.local_port)
+
+  def test_run_interleaving(self):
+      uiautomator.next_local_port = _create_next_local_port_stub(self.ports)
+
+      device1 = self.create_device("1")
+      device2 = self.create_device("2")
+
+      device1.server.start()
+      device2.server.start()
+
+      self.assertNotEqual(device1.server.local_port, device2.server.local_port)

test/test_server.py

@@ -29,21 +29,17 @@ def test_local_port_forwarded(self):
 
     def test_local_port_scanning(self):
         with patch('uiautomator.next_local_port') as next_local_port:
-            self.Adb.return_value.forward_list.return_value = []
+            self.Adb.return_value.device_serial.return_value = "abcd"
+            self.Adb.return_value.forward_list.side_effect = [[], [["abcd", "tcp:1234", "tcp:9008"]]]
             next_local_port.return_value = 1234
             self.assertEqual(AutomatorServer("abcd", None).local_port,
                              next_local_port.return_value)
 
-            next_local_port.return_value = 14321
-            self.Adb.return_value.forward_list.return_value = Exception("error")
-            self.assertEqual(AutomatorServer("abcd", None).local_port,
-                             next_local_port.return_value)
-
     def test_device_port(self):
         self.assertEqual(AutomatorServer().device_port, 9008)
 
     def test_start_success(self):
-        server = AutomatorServer()
+        server = AutomatorServer(local_port=1234)
         server.push = MagicMock()
         server.push.return_value = ["bundle.jar", "uiautomator-stub.jar"]
         server.ping = MagicMock()
@@ -53,7 +49,7 @@ def test_start_success(self):
         server.adb.cmd.assert_valled_onec_with('shell', 'uiautomator', 'runtest', 'bundle.jar', 'uiautomator-stub.jar', '-c', 'com.github.uiautomatorstub.Stub')
 
     def test_start_error(self):
-        server = AutomatorServer()
+        server = AutomatorServer(local_port=1234)
         server.push = MagicMock()
         server.push.return_value = ["bundle.jar", "uiautomator-stub.jar"]
         server.ping = MagicMock()
@@ -76,7 +72,7 @@ def side_effect():
                     raise result
                 return result
             JsonRPCMethod.return_value.side_effect = side_effect
-            server = AutomatorServer()
+            server = AutomatorServer(local_port=1234)
             server.start = MagicMock()
             server.stop = MagicMock()
             self.assertEqual("ok", server.jsonrpc.any_method())
@@ -89,14 +85,14 @@ def side_effect():
                     raise result
                 return result
             JsonRPCMethod.return_value.side_effect = side_effect
-            server = AutomatorServer()
+            server = AutomatorServer(local_port=1234)
             server.start = MagicMock()
             server.stop = MagicMock()
             self.assertEqual("ok", server.jsonrpc.any_method())
             server.start.assert_called_once_with()
         with patch("uiautomator.JsonRPCMethod") as JsonRPCMethod:
             JsonRPCMethod.return_value.side_effect = JsonRPCError(-32000-2, "error msg")
-            server = AutomatorServer()
+            server = AutomatorServer(local_port=1234)
             server.start = MagicMock()
             server.stop = MagicMock()
             with self.assertRaises(JsonRPCError):
@@ -105,15 +101,15 @@ def side_effect():
     def test_start_ping(self):
         with patch("uiautomator.JsonRPCClient") as JsonRPCClient:
             JsonRPCClient.return_value.ping.return_value = "pong"
-            server = AutomatorServer()
+            server = AutomatorServer(local_port=1234)
             server.adb = MagicMock()
             server.adb.forward.return_value = 0
             self.assertEqual(server.ping(), "pong")
 
     def test_start_ping_none(self):
         with patch("uiautomator.JsonRPCClient") as JsonRPCClient:
             JsonRPCClient.return_value.ping.side_effect = Exception("error")
-            server = AutomatorServer()
+            server = AutomatorServer(local_port=1234)
             self.assertEqual(server.ping(), None)
 
 
@@ -132,7 +128,7 @@ def tearDown(self):
         self.urlopen_patch.stop()
 
     def test_screenshot(self):
-        server = AutomatorServer()
+        server = AutomatorServer(local_port=1234)
         server.sdk_version = MagicMock()
         server.sdk_version.return_value = 17
         self.assertEqual(server.screenshot(), None)
@@ -145,15 +141,15 @@ def test_screenshot(self):
 
     def test_push(self):
         jars = ["bundle.jar", "uiautomator-stub.jar"]
-        server = AutomatorServer()
+        server = AutomatorServer(local_port=1234)
         server.adb = MagicMock()
         self.assertEqual(set(server.push()), set(jars))
         for args in server.adb.cmd.call_args_list:
             self.assertEqual(args[0][0], "push")
             self.assertEqual(args[0][2], "/data/local/tmp/")
 
     def test_stop_started_server(self):
-        server = AutomatorServer()
+        server = AutomatorServer(local_port=1234)
         server.adb = MagicMock()
         server.uiautomator_process = process = MagicMock()
         process.poll.return_value = None
@@ -174,7 +170,7 @@ def test_stop(self):
             b"USER     PID   PPID  VSIZE  RSS     WCHAN    PC         NAME\rsystem    372   126   635596 104808 ffffffff 00000000 S uiautomator"
         ]
         for r in results:
-            server = AutomatorServer()
+            server = AutomatorServer(local_port=1234)
             server.adb = MagicMock()
             server.adb.cmd.return_value.communicate.return_value = (r, "")
             server.stop()

uiautomator/__init__.py

@@ -312,9 +312,13 @@ def devices(self):
             raise EnvironmentError("adb is not working.")
         return dict([s.split("\t") for s in out[index + len(match):].strip().splitlines() if s.strip()])
 
-    def forward(self, local_port, device_port):
+    def forward(self, local_port, device_port, rebind=True):
         '''adb port forward. return 0 if success, else non-zero.'''
-        return self.cmd("forward", "tcp:%d" % local_port, "tcp:%d" % device_port).wait()
+        cmd = ["forward"]
+        if not rebind:
+            cmd.append("--no-rebind")
+        cmd += ["tcp:%d" % local_port, "tcp:%d" % device_port]
+        return self.cmd(*cmd).wait()
 
     def forward_list(self):
         '''adb forward --list'''
@@ -380,17 +384,11 @@ def __init__(self, serial=None, local_port=None, device_port=None, adb_server_ho
         self.adb = Adb(serial=serial, adb_server_host=adb_server_host, adb_server_port=adb_server_port)
         self.device_port = int(device_port) if device_port else DEVICE_PORT
         if local_port:
-            self.local_port = local_port
+            # Assume that the caller acquired the port correctly.
+            self.__local_port = local_port
         else:
-            try:  # first we will try to use the local port already adb forwarded
-                for s, lp, rp in self.adb.forward_list():
-                    if s == self.adb.device_serial() and rp == 'tcp:%d' % self.device_port:
-                        self.local_port = int(lp[4:])
-                        break
-                else:
-                    self.local_port = next_local_port(adb_server_host)
-            except:
-                self.local_port = next_local_port(adb_server_host)
+            # Port will be assigned later when communication actually starts.
+            self.__local_port = None
 
     def push(self):
         base_dir = os.path.dirname(__file__)
@@ -404,6 +402,31 @@ def install(self):
         for apk in self.__apk_files:
             self.adb.cmd("install", "-r -t", os.path.join(base_dir, apk)).wait()
 
+    def get_forwarded_port(self):
+        for s, lp, rp in self.adb.forward_list():
+            if s == self.adb.device_serial() and rp == 'tcp:%d' % self.device_port:
+                return int(lp[4:])
+        return None
+
+    @property
+    def local_port(self):
+        # If the port was already assigned, just return it.
+        if self.__local_port:
+            return self.__local_port
+
+        # Otherwise, find and acquire an available port.
+        while True:
+            # First, check whether there is an already set up port.
+            forwarded_port = self.get_forwarded_port()
+            if forwarded_port:
+                self.__local_port = forwarded_port
+                return self.__local_port
+
+            # If port is not set up yet, try to set it up.
+            port = next_local_port(self.adb.adb_server_host)
+            # Try to acquire the port, so that other processes don't take it.
+            self.adb.forward(port, self.device_port, rebind=False)
+
     @property
     def jsonrpc(self):
         return self.jsonrpc_wrap(timeout=int(os.environ.get("jsonrpc_timeout", 90)))