On Tue, Nov 19, 2013 at 3:27 PM, Yann Ylavic <ylavic....@gmail.com> wrote:
> On Mon, Nov 18, 2013 at 6:28 PM, William A. Rowe Jr.
> <wr...@rowe-clan.net>wrote:
>
>>
>> By closing our write-end of the connection, we can signal to the server
>> that we can't efficiently forward their response to the client (owing
>> to the fact that the server believes this to be a keep-alive connection,
>> and that we can't know where this specific response ends, until the
>> server has given up on receiving another keep-alive request).
>>
>
> This would be a good way to ensure the connection is closed by the origin,
> but half-closes are sometimes (and even often) mishandled, the origin might
> consider the connection is fully closed (unwritable) when the read-end is
> closed, that could be an issue too.
>
> Otherwise, the following patch could do the trick :
>
> Index: modules/http/http_filters.c
> ===================================================================
> --- modules/http/http_filters.c (revision 1541907)
> +++ modules/http/http_filters.c (working copy)
> @@ -291,13 +291,19 @@ apr_status_t ap_http_filter(ap_filter_t *f, apr_bu
> * denoted by C-L or T-E: chunked.
> *
> * Note that since the proxy uses this filter to handle the
> - * proxied *response*, proxy responses MUST be exempt.
> + * proxied *response*, proxy responses MUST be exempt, but
> + * ensure the connection is closed after the response.
> */
> - if (ctx->state == BODY_NONE && f->r->proxyreq !=
> PROXYREQ_RESPONSE) {
> - e = apr_bucket_eos_create(f->c->bucket_alloc);
> - APR_BRIGADE_INSERT_TAIL(b, e);
> - ctx->eos_sent = 1;
> - return APR_SUCCESS;
> + if (ctx->state == BODY_NONE) {
> + if (f->r->proxyreq != PROXYREQ_RESPONSE) {
> + e = apr_bucket_eos_create(f->c->bucket_alloc);
> + APR_BRIGADE_INSERT_TAIL(b, e);
> + ctx->eos_sent = 1;
> + return APR_SUCCESS;
> + }
> + f->r->
>
> connection->keepalive = AP_CONN_CLOSE;
> + apr_socket_shutdown(ap_get_conn_socket(f->r->connection),
> + APR_SHUTDOWN_WRITE);
> }
>
Actually the shutdown would break SSL (which may need to write during
read, ~roughly~).
Maybe just closing the connection at the end of the response is enough,
which is assured by setting connection->keepalive to AP_CONN_CLOSE here and
ap_proxy_http_response() setting the backend->close below in that case.
>
> /* Since we're about to read data, send 100-Continue if needed.
> Index: modules/proxy/mod_proxy_http.c
> ===================================================================
> --- modules/proxy/mod_proxy_http.c (revision 1541907)
> +++ modules/proxy/mod_proxy_http.c (working copy)
> @@ -1681,6 +1681,7 @@ int
>
> ap_proxy_http_process_response(apr_pool_t * p,
> continue;
> }
> else if (rv == APR_EOF) {
> + backend->close = 1;
> break;
> }
> else if (rv != APR_SUCCESS) {
> @@ -1825,6 +1826,11 @@ int ap_proxy_http_process_response(apr_pool_t * p,
> return DONE;
> }
>
> + /* If the underlying backend connection is to be closed, close it. */
> + if (origin->keepalive == AP_CONN_CLOSE) {
> + backend->close = 1;
> + }
> +
> return OK;
> }
>
> [END]
>
>
> Regards,
> Yann.
>
>
