Merge branch 'master' into 4951-request-vm

[arvados.git] / sdk / python / tests / run_test_server.py

diff --git a/sdk/python/tests/run_test_server.py b/sdk/python/tests/run_test_server.py
index dce1e73ef7dd13223ff1b22392fba7a2c2c2f4ea..5fee9eb0ec193d0cd4c3496480bf8b103727ea80 100644 (file)
--- a/sdk/python/tests/run_test_server.py
+++ b/sdk/python/tests/run_test_server.py
@@ -9,6 +9,7 @@ import random
 import re
 import shutil
 import signal
 import re
 import shutil
 import signal

+import socket

 import subprocess
 import string
 import sys
 import subprocess
 import string
 import sys


@@ -94,28 +95,22 @@ def kill_server_pid(pidfile, wait=10, passenger_root=False):
         pass
 
 def find_available_port():
         pass
 
 def find_available_port():

-    """Return a port number that is not in use right now.
+    """Return an IPv4 port number that is not in use right now.
+
+    We assume whoever needs to use the returned port is able to reuse
+    a recently used port without waiting for TIME_WAIT (see
+    SO_REUSEADDR / SO_REUSEPORT).

 
     Some opportunity for races here, but it's better than choosing
     something at random and not checking at all. If all of our servers
     (hey Passenger) knew that listening on port 0 was a thing, the OS
     would take care of the races, and this wouldn't be needed at all.
     """
 
     Some opportunity for races here, but it's better than choosing
     something at random and not checking at all. If all of our servers
     (hey Passenger) knew that listening on port 0 was a thing, the OS
     would take care of the races, and this wouldn't be needed at all.
     """

-    port = None
-    while port is None:
-        port = random.randint(20000, 40000)
-        port_hex = ':%04x ' % port
-        try:
-            with open('/proc/net/tcp', 'r') as f:
-                for line in f:
-                    if 0 <= string.find(line, port_hex):
-                        port = None
-                        break
-        except OSError:
-            # This isn't going so well. Just use the random port.
-            pass
-        except IOError:
-            pass
+
+    sock = socket.socket()
+    sock.bind(('0.0.0.0', 0))
+    port = sock.getsockname()[1]
+    sock.close()

     return port
 
 def run(leave_running_atexit=False):
     return port
 
 def run(leave_running_atexit=False):