Gson Codec

This module adds support for encoding and decoding JSON via the Gson library.

Add GsonEncoder and/or GsonDecoder to your Feign.Builder like so:

GitHub github = Feign.builder()
                     .encoder(new GsonEncoder())
                     .decoder(new GsonDecoder())
                     .target(GitHub.class, "https://api.github.com");

Map<String, Object> and Numbers

The default constructors of GsonEncoder and GsonDecoder decoder numbers in Map<String, Object> as Integer type. This prevents reading {"counter", "1"} as Map.of("counter", 1.0).

To change this, please use constructors that accept a Gson object.