Retrofit integration

Retrofit is a library that simplifies the access to RESTful services by turning an HTTP API into a Java interface.

Armeria provides a builder class called ArmeriaRetrofit that builds an alternative Retrofit implementation that replaces the networking engine of Retrofit from OkHttp to Armeria. By doing so, you get the following benefits:

  • Better performance, thanks to Netty and its JNI-based I/O and TLS implementation
  • Leverage other advanced features of Armeria, such as client-side load-balancing and service discovery
  • Cleartext HTTP/2 support, as known as h2c

First, you need armeria-retrofit2 dependency:

build.gradle
dependencies {
    implementation platform('com.linecorp.armeria:armeria-bom:1.28.2')

    ...
    implementation 'com.linecorp.armeria:armeria-retrofit2'
}

Now, you can build Retrofit using ArmeriaRetrofit.builder():

import com.linecorp.armeria.client.retrofit2.ArmeriaRetrofit;

import retrofit2.Retrofit;
import retrofit2.converter.jackson.JacksonConverterFactory;
import retrofit2.http.GET;
import retrofit2.http.Path;

class UserInfo { ... }

interface MyService {
    @GET("/userInfo/{id}")
    CompletableFuture<UserInfo> getUserInfo(@Path("id") String id);
}

Retrofit retrofit = ArmeriaRetrofit.builder("http://localhost:8080/")
                                   .addConverterFactory(JacksonConverterFactory.create())
                                   .build();

MyService service = retrofit.create(MyService.class);
UserInfo userInfo = service.getUserInfo("foo").get();

For more information, please refer to the API documentation of the com.linecorp.armeria.client.retrofit2 package.