php server side events [sse]
mdounin at mdounin.ru
Wed Aug 26 21:08:18 UTC 2015
On Wed, Aug 26, 2015 at 12:33:48PM -0700, dmiller at amfes.com wrote:
> I have several virtual servers operating with php-fpm perfectly fine.
> Buffering/caching with Wordpress is great. But now...
> I'm trying to implement a new site that uses php for server-side events to
> stream live updates to clients. This is, I believe, properly done with an
> infinite loop in php that will send events as they occur. The problem is
> the events seem to be getting buffered and don't appear.
> If I write the php program to end after sending an event then it works. If
> I restart php-fpm then it works - at least for a while.
> I've tried numerous config options - obviously what I'm trying isn't
> working. Any suggestions?
By default, nginx only starts sending data to a client once it has
a full buffer ready. If you want to stream data immediately,
you have to switch off buffering - either with the fastcgi_buffering
directive, or using the X-Accel-Buffering header in a response.
See http://nginx.org/r/fastcgi_buffering for details.
Additionally, there are some buffering option in PHP. I'm not a
PHP expert, but likely flush() function will help if the problem
is on PHP side, see http://php.net/manual/en/function.flush.php.
More information about the nginx