Question

Is it possible to configure nginx to query a service (not DNS) to determine the proxy_pass destination based on the currently-requested URI?

For example:

1. Client requests http://somesite.tld/somepage, which needs to be proxied.
2. nginx connects to the resolving service and sends the request URI which is used to determine the proxy destination.
3. The resolving service responds, providing the hostname of the destination.
4. The client’s request is redirected to the given destination.

If this is not supported, what would be a good way to do this? I could proxy_pass to a resolver+proxy, but would prefer to let nginx handle the proxying directly to the destination. Note that the resolver needs to be queried because the destinations for each URI may change.

Thanks 🙂

Answer 1

I don’t see a way to achieve what you are asking.

However if you are simply looking to map request args to hostnames (and they don’t change a lot), then you could probably use Nginx’s map module.

You might also be able to do something using mod_lua, but it would likely be terribly hackish.