Question about allowing a percentage of traffic

[Valentin V. Bartenev]

On Wednesday 21 March 2012 22:44:26 spacerobot wrote:
> This is about traffic control, in the case we get slammed by heavier
> traffic than expected we want to be able to gracefully only allow part
> of the users' requests to come through.
> 
> In my current nginx config, I have a white list based on a
> $http_x_user_id header in the request and only allow traffic from those
> users.
> 
> The way I did it was a condition in the location / block:
> 
> if ( $http_x_user_id !~ (THE_WHITE_LIST_OF_IDs) ) {
>   return 503;
> }
> 
> (We can control the white list dynamically and re-render the config with
> Chef.)
> 
> What I also need to do is to allow a certain percentage of requests from
> users whose id is not in the white list. For example, I need to be able
> to allow 30% of users in addition to those in the white list to get
> access. Based on my limited knowledge on nginx, I have no idea on what's
> the best way to do it.
> 
> Any insights?
> 

Perhaps the split clients module will be suitable for you:

http://nginx.org/en/docs/http/ngx_http_split_clients_module.html

 wbr, Valentin V. Bartenev