[libmicrohttpd] Connection: Keep-Alive

[Derrick Bradbury]

Hi all...

I've been putting together an app that requires a persistant connection for 30 seconds, drop and re-establish.

Everything is working except for the keepalive...

>From everything I've read, HTTP/1.1 should have keepalive enabled by default, and in MHD, you must close it by adding the header (Connection: close).

Problem is, that when I get a request, the header has a "keep-alive" request, but MHD returns a "Connection: close"...

* About to connect() to 127.0.0.1 port 5000 (#0)
*   Trying 127.0.0.1... connected
* Connected to 127.0.0.1 (127.0.0.1) port 5000 (#0)
> GET /ready.html HTTP/1.1
> User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.14.0.0 zlib/1.2.3 libidn/1.18 libssh2/1.4.2
> Host: 127.0.0.1:5000
> Accept: */*
> Connection: Keep-Alive
>
< HTTP/1.1 200 OK
< Connection: close
< Content-Length: 2
<
1
* Closing connection #0
* About to connect() to 127.0.0.1 port 5000 (#0)
*   Trying 127.0.0.1... connected
* Connected to 127.0.0.1 (127.0.0.1) port 5000 (#0)
> GET /classify.html?url="" HTTP/1.1
> User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.14.0.0 zlib/1.2.3 libidn/1.18 libssh2/1.4.2
> Host: 127.0.0.1:5000
> Accept: */*
> Connection: Keep-Alive
>
< HTTP/1.1 200 OK
< Connection: close
< Content-Length: 6
<
33
66
* Closing connection #0


If I manually add a "Connection: Keep-Alive" header, the client thinks there should be a persistant connection, but the server still closes the connection:

* About to connect() to 127.0.0.1 port 5000 (#0)
*   Trying 127.0.0.1... connected
* Connected to 127.0.0.1 (127.0.0.1) port 5000 (#0)
> GET /ready.html HTTP/1.1
> User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.14.0.0 zlib/1.2.3 libidn/1.18 libssh2/1.4.2
> Host: 127.0.0.1:5000
> Accept: */*
> Connection: Keep-Alive
>
< HTTP/1.1 200 OK
< Content-Length: 2
< Connection: keep-alive
<
1
* Connection #0 to host 127.0.0.1 left intact
* Connection #0 seems to be dead!
* Closing connection #0
* About to connect() to 127.0.0.1 port 5000 (#0)
*   Trying 127.0.0.1... connected
* Connected to 127.0.0.1 (127.0.0.1) port 5000 (#0)
> GET /classify.html?url="" HTTP/1.1
> User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.14.0.0 zlib/1.2.3 libidn/1.18 libssh2/1.4.2
> Host: 127.0.0.1:5000
> Accept: */*
> Connection: Keep-Alive
>
< HTTP/1.1 200 OK
< Content-Length: 4
< Connection: keep-alive
<
998
* Connection #0 to host 127.0.0.1 left intact
* Connection #0 seems to be dead!
* Closing connection #0



Here is my daemon definition:
  daemon = MHD_start_daemon (MHD_USE_SELECT_INTERNALLY | MHD_SUPPRESS_DATE_NO_CLOCK
                        | MHD_USE_EPOLL_LINUX_ONLY | MHD_USE_EPOLL_TURBO,
                        options.port,
                        NULL, NULL, &answer_to_connection, NULL,
                        MHD_OPTION_THREAD_POOL_SIZE, (unsigned int) options.threads,
                        MHD_OPTION_CONNECTION_LIMIT, (unsigned int) 12000, MHD_OPTION_END);
 

and my response being built:

 response = MHD_create_response_from_buffer (strlen (page), (void*) page, MHD_RESPMEM_PERSISTENT);
  ret = MHD_add_response_header(response,"Connection","keep-alive");

  ret = MHD_queue_response (connection, MHD_HTTP_OK, response);
 
  MHD_destroy_response (response);


Am I needing a different response, or setting?

Thanks!
Derrick