[BEAM-10618] subprocess_server.py: Fallback to AF_INET6 family when finding free port (#12438)
* Use IPv6 socket when finding free port
* Only use AF_INET6 as a fallback
diff --git a/sdks/python/apache_beam/utils/subprocess_server.py b/sdks/python/apache_beam/utils/subprocess_server.py
index 0d40181..018a837 100644
--- a/sdks/python/apache_beam/utils/subprocess_server.py
+++ b/sdks/python/apache_beam/utils/subprocess_server.py
@@ -291,11 +291,20 @@
if port:
return port
else:
- s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+ try:
+ s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+ except OSError as e:
+ # [Errno 97] Address family not supported by protocol
+ # Likely indicates we are in an IPv6-only environment (BEAM-10618). Try
+ # again with AF_INET6.
+ if e.errno == 97:
+ s = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
+ else:
+ raise e
+
sockets.append(s)
s.bind(('localhost', 0))
- _, free_port = s.getsockname()
- return free_port
+ return s.getsockname()[1]
ports = list(map(find_free_port, ports))
# Close sockets only now to avoid the same port to be chosen twice
