Option to disable buffering in uwsgi module

[Peter Smit]

(This is my first message to this list, please let me know if I'm
doing something wrong!)

In developing a comet style application in a uwsgi/nginx setup I
noticed that nginx always buffers the response when uwsgi_pass is
used.

I'm not sure or there is any particular reason why this is done,
except for the fact that the uwsgi code is originally based on the
fastcgi module where indeed buffering is unavoidable. I think however
that it makes sense to give the option of disabling buffering with
uwsgi.

I actually already went ahead and wrote a patch that does exactly
this. It introduces a uwsgi_buffering flag and now adheres to the
"X-Accel-Buffering" header. I have only limited capabilities to test
this patch, but for me it does exactly that, disabling the buffer.

Could some of you review this patch and if it is ok, could it be
introduced in nginx?

I made the patch on the 1.1.0 source. I attached it and included it
inline below this message. Let me know if I should give it in a
different format.

Regards,

Peter Smit



--- nginx-1.1.0/src/http/modules/ngx_http_uwsgi_module.c	2011-07-29
18:33:03.000000000 +0300
+++ nginx-1.1.0-uwsgi_buffering/src/http/modules/ngx_http_uwsgi_module.c	2011-08-04
13:16:54.381528459 +0300
@@ -123,6 +123,13 @@
       offsetof(ngx_http_uwsgi_loc_conf_t, upstream.store_access),
       NULL },

+    { ngx_string("uwsgi_buffering"),
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE123,
+      ngx_conf_set_flag_slot,
+      NGX_HTTP_LOC_CONF_OFFSET,
+      offsetof(ngx_http_uwsgi_loc_conf_t, upstream.buffering),
+      NULL },
+
     { ngx_string("uwsgi_ignore_client_abort"),
       NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
       ngx_conf_set_flag_slot,
@@ -445,7 +452,7 @@
     u->abort_request = ngx_http_uwsgi_abort_request;
     u->finalize_request = ngx_http_uwsgi_finalize_request;

-    u->buffering = 1;
+    u->buffering = uwcf->upstream.buffering;

     u->pipe = ngx_pcalloc(r->pool, sizeof(ngx_event_pipe_t));
     if (u->pipe == NULL) {
@@ -1083,6 +1090,8 @@
     /* "uwsgi_cyclic_temp_file" is disabled */
     conf->upstream.cyclic_temp_file = 0;

+    conf->upstream.change_buffering = 1;
+
     ngx_str_set(&conf->upstream.module, "uwsgi");

     return conf;
-------------- next part --------------
A non-text attachment was scrubbed...
Name: nginx-1.1.0_uwsgi_buffering_patch
Type: application/octet-stream
Size: 1252 bytes
Desc: not available
URL: <http://mailman.nginx.org/pipermail/nginx-devel/attachments/20110804/fd81b635/attachment.obj>