WS02 API Manager malformed request to endpoint URL

Question

We have our API being managed by WS02 API manager, but there seems to be some issue with the way it constructs the outgoing request into the configured endpoint URL. We see this sort of error from our endpoint when we make a request to the API manager:

Cannot bind to address "http://<HOST>:<PORT>http://<HOST>:<PORT>/<RESOURCE>

The URL is clearly incorrect as it is prepending the host part of the URL twice. We've put a debugging proxy in between the API manager and our endpoint and it shows the outgoing request looks like this:

GET http://<HOST>:<PORT>/<RESOURCE> HTTP/1.1
...
Host: <HOST>:<PORT>

It isn't normal for the host to be included in the first line; that should come from the "Host" header. But as it is, it makes sense we are getting the above error. Note, when we proxy this through something like Nginx, it works fine, but the server we are actually using for our endpoint doesn't like it. I'm guessing Nginx has been written in such a way so that it can resolve this kind of (technically incorrect) request.

Answer 1

We are adding propery 'POST_TO_URI' to our synapse API configuration in order to make the outgoing URL a complete URL [1]. This is useful when sending the messages through a proxy server. You can remove that property by modifying your API in AM_HOME/repository/deployment/server/synapse-configs/default/api/ directory. Remove the below property in your relevant APIs which sending requests to such backend servers.

<property name="POST_TO_URI" value="true" scope="axis2"/>

[1]https://docs.wso2.org/display/ESB460/HTTP+Transport+Properties