如何使用AsyncRestTemplate拦截AsyncClientHttpRequest？

Question

I'm developing an asynchronous REST client using the spring AsyncRestTemplate helper class.

The client needs to send a token in the header of every requests.

It is possible to add an interceptor when using the HttpAsyncClient (of http://hc.apache.org/httpcomponents-asyncclient-4.0.x/index.html ) as the underlying http client of the rest template :

HttpRequestInterceptor interceptor = (request, context) -> request.addHeader("token", "value");

CloseableHttpAsyncClient client = HttpAsyncClients.custom()
  .addInterceptorLast(interceptor)
  .build();

HttpComponentsAsyncClientHttpRequestFactory factory = new HttpComponentsAsyncClientHttpRequestFactory(client);

AsyncRestTemplate template = new AsyncRestTemplate(factory);

However, if for some reason I need to change the underlying client, this interceptor can no longer be used.

Is there any other way to intercept an AsyncClientHttpRequest using an interceptor agnostic of the underlying http client ?

Answer 1

No, not through the AsyncRestTemplate and not through the HttpAsyncClient . Neither of those interfaces provide a mutator for adding HttpRequestInterceptor instances.

As far as I know, only the builders for these are mutable. So even if you could get the request factory or the client, you'd still not be able to change them.

You have to intercept their actual creation, which, depending on your setup, may not be possible.