Pass base url or host as a param

I have a use case where I have a list of hosts, I need to loop over those hosts and make the same api call for each of them. I don’t want a hardcoded base url as that would mean creating a new feign client for each api call.

I would like to do something like:

public class FeignBaseUrlParamTest {

    @Test
    public void testIt() {
        MyClient client = Feign.builder().target(Target.EmptyTarget.create(MyClient.class));
        client.internalService("http://localhost:8080");
    }
}

interface MyClient {
    @RequestLine("GET {baseUrl}/internal-service")
    String internalService(@Param("baseUrl") String host);
}

However this encodes the base url part and the following exception occurs:

feign.RetryableException: no protocol: http%3A//localhost%3A8080/internal-service executing GET http%3A//localhost%3A8080/internal-service

I tried to create a Target implementation which gets the url out and decodes everything before the path. However it is not possible as you can only perform additions to the url from that context.

[codefromthecrypt]

I think you want to just add an unannotated URI param

interface MyClient { @RequestLine(“GET /internal-service”) String internalService(URI baseUrl); }

[tomradcliffe]

That works perfectly. Thanks