Issue 26404: socketserver context manager (original) (raw)
Created on 2016-02-21 20:55 by palaviv, last changed 2022-04-11 14:58 by admin. This issue is now closed.
Messages (12)
Author: Aviv Palivoda (palaviv) *
Date: 2016-02-21 20:55
As Martin commented on my patch at issue 26392 the socketserver.server_close is like the file close. That made me think that we should add a context manager to the socketserver.
Author: Martin Panter (martin.panter) * 
Date: 2016-02-22 10:56
I would support this change, as long as we aren’t supporting using server_close() to stop the server loop at the same time.
It might be worth updating other example code that uses server_close(), in particular in the xmlrpc.server documentation.
Author: Aviv Palivoda (palaviv) *
Date: 2016-02-22 18:38
Only closing the server :).
- Did the changes requested in the CR.
- Changed the example's in xmlrpc.server, http.server to use context manager.
- Changed the xmlrpc.server, http.server server implementation when running python -m {xmlrpc.server, http.server} to use context manager.
Author: Martin Panter (martin.panter) *
Date: 2016-02-24 01:59
Thanks, the patch looks pretty good to me. I left some comments about minor things. Also, someone will need to write a What’s New entry.
Author: Aviv Palivoda (palaviv) *
Date: 2016-02-24 09:02
Updated the patch:
- Did the changes requested in the CR.
- Changed the example's in wsgiref.simple_server to use context manager.
- Added What's New entry.
Author: Aviv Palivoda (palaviv) *
Date: 2016-02-25 17:26
updated the patch according to the CR comments.
Author: Terry J. Reedy (terry.reedy) *
Date: 2016-02-27 09:37
This seems like an appropriate enhancement. I notice that the serve_forever examples did not previously have server_close(). Was this an oversight or will the server_close in exit just be a no-op?
Author: Aviv Palivoda (palaviv) *
Date: 2016-02-29 14:17
The examples did not close the server but I am not sure if that was a mistake. The server is not being closed only on examples where it is expected to run until there is a keyboard interrupt. However you can see that when you send keyboard interrupt to a server you start using python -m http.server you will do close the server.
Author: Martin Panter (martin.panter) *
Date: 2016-02-29 22:54
Server_close() was only documentated last year; see Issue 23254. For the examples that run until you interrupt them, the servers currently emit a resource warning (in addition to the KeyboardInterrupt traceback and the Python 2 bytes warnings):
$ python -bWall TCPServer.py 127.0.0.1 wrote: TCPServer.py:16: BytesWarning: str() on a bytes instance print(self.data) b'hello world with TCP' 127.0.0.1 wrote: TCPServer.py:16: BytesWarning: str() on a bytes instance print(self.data) b'python is nice' ^CTraceback (most recent call last): File "TCPServer.py", line 28, in server.serve_forever() File "/usr/lib/python3.5/socketserver.py", line 237, in serve_forever ready = selector.select(poll_interval) File "/usr/lib/python3.5/selectors.py", line 367, in select fd_event_list = self._poll.poll(timeout) KeyboardInterrupt sys:1: ResourceWarning: unclosed <socket.socket fd=3, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('127.0.0.1', 9999)> [Exit 1]
If you ignore the warning, there isn’t much effective difference, because the socket gets closed when the process exits, or if you are lucky, when Python garbage collects the global “server” object. But IMO it is bad practice not to clean up resources properly, especially in an API example.
Author: Terry J. Reedy (terry.reedy) *
Date: 2016-03-01 06:37
I agree and consider this is an argument for adding the context manager methods and using them with 'with' in the examples.
Author: Roundup Robot (python-dev) 
Date: 2016-04-13 02:41
New changeset 5c4303c46a18 by Martin Panter in branch 'default': Issue #26404: Add context manager to socketserver, by Aviv Palivoda https://hg.python.org/cpython/rev/5c4303c46a18
Author: Martin Panter (martin.panter) *
Date: 2016-04-13 04:00
Thanks for the patch Aviv. I made a few minor English grammar etc tweaks in the version I committed, as pointed out in the review comments.
History
Date
User
Action
Args
2022-04-11 14:58:27
admin
set
github: 70592
2016-04-13 04:00:06
martin.panter
set
status: open -> closed
resolution: fixed
messages: +
stage: patch review -> resolved
2016-04-13 02:41:30
python-dev
set
nosy: + python-dev
messages: +
2016-03-01 06:37:00
terry.reedy
set
messages: +
2016-02-29 22:54:51
martin.panter
set
messages: +
2016-02-29 14:17:57
palaviv
set
messages: +
2016-02-27 09:37:39
terry.reedy
set
nosy: + terry.reedy
messages: +
2016-02-25 17:26:50
palaviv
set
files: + socketserver_context_manager4.patch
messages: +
2016-02-24 09:02:59
palaviv
set
files: + socketserver_context_manager3.patch
messages: +
2016-02-24 01:59:14
martin.panter
set
messages: +
stage: patch review
2016-02-22 18:38:50
palaviv
set
files: + socketserver_context_manager2.patch
messages: +
2016-02-22 10:56:22
martin.panter
set
messages: +
2016-02-21 20:55:10
palaviv
create