Library that adapts interface created by Retrofit using annotations on declared methods to define response mocks.

• Requirements
• Getting started
• Usage
• Contributing
• License
• Credits

• Retrofit 3.0.0 or higher
• Kotlin 1.9.0 or higher (if using Kotlin)
• Java 17 or higher
• Gradle 7.6.3 or higher

To include Retromock in your project, you have to add buildscript dependencies in your project level build.gradle or build.gradle.kts:

Groovy

buildscript {
    repositories {
        mavenCentral()
    }
}

KotlinDSL

buildscript {
    repositories {
        mavenCentral()
    }
}

Then, you can include the library in your module's build.gradle or build.gradle.kts:

Groovy

implementation 'com.infinum:retromock:1.3.0'

KotlinDSL

implementation("com.infinum:retromock:1.3.0")

Some examples are in Java, but Kotlin examples (including coroutine support) can be found in the full specification.

Java

Retromock retromock = new Retromock.Builder()
  .retrofit(retrofit)
  .build();

Kotlin

val retromock = Retromock.Builder()
 .retrofit(retrofit)
 .build()

Java

Service service = retromock.create(Service.class);

Kotlin

val service = retromock.create(Service::class.java)

Java

public interface Service {

  @Mock
  @MockResponse(body = "{\"name\":\"John\", \"surname\":\"Doe\"}")
  @GET("/endpoint")
  Call<User> getUser();
}

Kotlin

interface Service {
    @Mock
    @MockResponse(body = "{\"name\":\"John\", \"surname\":\"Doe\"}")
    @GET("/endpoint")
    suspend fun getUser(): User
}

Java

Call<User> = service.getUser();

Kotlin

val user = service.getUser()

If you would like to load response from a stream set a default body factory that loads a response stream by a body parameter(response.json) in annotation.

Java

Retromock retromock = new Retromock.Builder()
  .retrofit(retrofit)
  .defaultBodyFactory(...)
  .build();

public interface Service {

  @Mock
  @MockResponse(body = "response.json")
  @GET("/endpoint")
  Call<User> getUser();
}

For more complex scenarios where you need to generate responses based on method parameters or apply custom logic, use @MockResponseProvider:

Java

public interface Service {
  @Mock
  @MockResponseProvider(UserProvider.class)
  @GET("/users")
  Call<User> getUser(String userId);
}

public class UserProvider {
  @ProvidesMock
  public Response getUser(String userId) {
    String body = "{\"id\":\"" + userId + "\", \"name\":\"User " + userId + "\"}";
    return new Response.Builder()
        .body(body)
        .build();
  }
}

Java

Retromock retromock = new Retromock.Builder()
  .retrofit(retrofit)
  .defaultBodyFactory(context.getAssets()::open)
  .build();

public interface Service {

  @Mock
  @MockResponse(body = "retromock/response.json")
  @GET("/endpoint")
  Call<User> getUser();
}

Save a response body content in file named retromock/response.json.

If you use Retromock only in some variants you can exclude files with mock responses from final .apk with configuration similar to:

applicationVariants.all { variant ->
  if (variant.buildType.name.contains('production')) {
    variant.mergeAssets.doLast {
      delete(fileTree(dir: variant.mergeAssets.outputDir, includes: ['**/retromock/*']))
    }
  }
}

Note: if you set custom default body factory and do not declare a bodyFactory parameter in @MockResponse annotation your body factory will be called with value of body parameter. That also applies if you don't specificaly set a body - in that case body is empty by default. If you wouldn't like to handle the case of empty body wrap your default body factory into NonEmptyBodyFactory class as follows:

Java

Retromock retromock = new Retromock.Builder()
  .retrofit(retrofit)
  .defaultBodyFactory(new NonEmptyBodyFactory(...))
  .build();

The library does not require any ProGuard rules.

However, you might need rules for Retrofit and its dependencies.

We believe that the community can help us improve and build better a product. Please refer to our contributing guide to learn about the types of contributions we accept and the process for submitting them.

To ensure that our community remains respectful and professional, we defined a code of conduct that we expect all contributors to follow.

For easier developing a samples with proper implementations are provided.

We appreciate your interest and look forward to your contributions.

Copyright 2019 Infinum

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

Maintained and sponsored by Infinum.