filter-json-jackson-jaxrs

Partial Response - JAX-RS Jackson JSON Filter

This project makes it easy to add partial response filtering to your JAX-RS based REST API.

If your REST api is built using JAX-RS 2.0 and uses Jackson to do the JSON serialisation from Java POJOs then this library should be able to help you.

Usage

To use this library in your Maven project simply include the dependency

<dependency>
  <groupId>com.pressassociation.partial-response</groupId>
  <artifactId>filter-json-jackson-jaxrs</artifactId>
  <version>1.0</version>
</dependency>

Depending on your JAX-RS implementation you may also need to configure your JAX-RS environment so that it is aware of the FilteredObjectMapperResolver. In general this involves including an instance of this class in your Application providers list.

The FilteredObjectMapperResolver is annotated with JSR-330 @Inject annotations as a mechanism to resolve it's dependencies, if you are using a container or environment that doesn't support JSR-330 then you will need to configure the FilteredObjectMapperResolver manually. You may also need to do this if you plan on changing the default fields request parameter that is used to populate the partial response pattern from the incoming request.

Advanced Usage

If you are already customising the ObjectMapper for your JAX-RS Jackson application then you should look at the JacksonRequestParamFilter. This class encapsulates the configuration of ObjectMapper for re-use without the baggage brought by a full JAX-RS filter. To use you should obtain an instance of JacksonRequestParamFilter via your favourite DI method and call its configurePartialResponse method on the ObjectMapper instance.

@Provider
@Singleton
public class IndentedObjectMapperResolver implements ContextResolver<ObjectMapper> {

  private final JacksonRequestParamFilter paramFilter;

  @Inject
  public IndentedObjectMapperResolver(JacksonRequestParamFilter paramFilter) {
    this.paramFilter = checkNotNull(paramFilter);
  }

  @Override
  public ObjectMapper getContext(Class<?> type) {
    ObjectMapper mapper = new ObjectMapper();

    // do my own customisation
    mapper.enable(SerializationFeature.INDENT_OUTPUT);

    // configure the partial response filter
    paramFilter.configurePartialResponse(mapper);

    return mapper;
  }
}