upgrade to 1-9.15 caused block requests

[Maxim Dounin]

Hello!

On Wed, Nov 21, 2018 at 01:47:40PM -0500, Ortal wrote:

> Hi, 
> I am developing my own nginx module, I am getting a post requests, parse the
> data and send 204.
> I worked with nginx version release-1.9.15, and I am trying to upgrade to
> version release-1.15.5.
> After the upgrade post requests with payload larger then 1M are getting
> blocked. 
> From the nginx log:
> 2018/11/21 20:03:10 [debug] 13470#0: *2 http reading blocked

Most likely, this is a bug in your module which started to 
consistently manifest itself after the upgrade.

The "http reading blocked" message is printed by the 
ngx_http_block_reading() function, which is used as a request read 
event handler when nginx doesn't want read anything from the 
network.  If you see this message and think this is a problem, 
most likely you've forgot to update request event handlers at some 
point.

In particular, a common mistake is to try to read the request body 
in a phase handler, and then try to continue request processing by 
calling ngx_http_core_run_phases() without restoring the 
r->write_event_handler as well.

If you need further help with finding out what goes wrong, 
consider posting code of your module (preferably a minimal yet 
working test module) and a full debugging log which demonstrates 
the problem.

-- 
Maxim Dounin
http://mdounin.ru/