how to construct a response dynamically?

ming.zhang.china · 2014-02-10T11:30:24+00:00

Hello agentzhAs usual thank you for your prompt and valuable responses. Let me see how much I can assist in adding the comments to the codeOn Saturday, March...

how to construct a response dynamically?

ming.zhang.china

Hi All

Wonder how to implement this in lua?

when get a POST/GET request, I need to send multiple different HEAD requests to various upstream servers. Then base on the results, pick one upstream server for the actual request.

I checked this http://sosedoff.com/2012/06/11/dynamic-nginx-upstreams-with-lua-and-redis.html, which might be close. Wonder how to send multiple HEAD requests at same time? Looks like I shall use http://wiki.nginx.org/HttpLuaModule#ngx.location.capture_multi. But the example uses locations. In my case, the servers' IP are dynamically generated.

Thanks.

Ming

bjornar.ness

kl. 04:30:24 UTC+1 mandag 10. februar 2014 skrev ming zhang følgende:

Hi All

Wonder how to implement this in lua?

when get a POST/GET request, I need to send multiple different HEAD requests to various upstream servers. Then base on the results, pick one upstream server for the actual request.

Hi

use ngx.thread and resty.http

--
Bj(/)rnar

ming.zhang.china

Thanks for your reply.. Wonder why could not use ngx.location.capture_multi? if it can work, certainly it is more cleaner & simpler than using these two modules.

Ming

On Mon, Feb 10, 2014 at 5:10 PM, Bjørnar Ness <bjorn...@gmail.com> wrote:

kl. 04:30:24 UTC+1 mandag 10. februar 2014 skrev ming zhang følgende:

Hi All

Wonder how to implement this in lua?

when get a POST/GET request, I need to send multiple different HEAD requests to various upstream servers. Then base on the results, pick one upstream server for the actual request.

Hi

use ngx.thread and resty.http

--
Bj(/)rnar

.

agentzh

Hello!

On Mon, Feb 10, 2014 at 7:13 PM, ming zhang wrote:
> Thanks for your reply.. Wonder why could not use ngx.location.capture_multi?

Yes you could. You can just pass your IP address into your
subrequest's location and use an Nginx variable in your proxy_pass for
the place of the hostname. This should be similar to the following
sample:

    http://openresty.org/#DynamicRoutingBasedOnRedis

You just need to pass the host names to your subrequest and make it
end up in the $target variable, for example.

Regards,
-agentzh

ming.zhang.china

nice! this will be an elegant solution. thanks!

ming

On Tue, Feb 11, 2014 at 3:22 PM, Yichun Zhang (agentzh) <age...@gmail.com> wrote:

Hello!

On Mon, Feb 10, 2014 at 7:13 PM, ming zhang wrote:
> Thanks for your reply.. Wonder why could not use ngx.location.capture_multi?

Yes you could. You can just pass your IP address into your
subrequest's location and use an Nginx variable in your proxy_pass for
the place of the hostname. This should be similar to the following
sample:

http://openresty.org/#DynamicRoutingBasedOnRedis

You just need to pass the host names to your subrequest and make it
end up in the $target variable, for example.

Regards,
-agentzh

.