Header authentication bundle for Dropwizard

This bundle provides the ability to define a header to take a user (or 'principal') ID from, and use as an authenticated user throughout the application. This is mainly intended for use in applications that sit behind a reverse proxy that will extract or provide the user information as required. This bundle also registers the RolesAllowedDynamic feature, meaning you can add @RolesAllowed annotations to restrict calls as needed.

It's important that any application that relies on authentication done in this manner is properly secured from malicious requests (for example, by locking down the application to only accept connections from the upstream proxy)

Maven Setup

<dependency>
  <groupId>engineer.nightowl</groupId>
  <artifactId>dw-header-auth-bundle</artifactId>
  <version>1.3.5-1</version>
</dependency>

Getting Started

Implement the HeaderAuthConfiguration:

public class SampleConfiguration extends Configuration implements HeaderAuthConfiguration {

  @NotNull
  @JsonProperty("authentication")
  private HeaderAuthConfiguration headerAuthConfiguration;

  @Override
  public HeaderAuthConfiguration getHeaderAuthConfiguration() {
    return headerAuthConfiguration;
  }
}

Add the bundle:

public class SampleService extends Application<SampleConfiguration> {
    public static void main(String[] args) throws Exception {
        new SampleService().run(args);
    }

    @Override
    public void initialize(Bootstrap<SampleConfiguration> bootstrap) {
        
        // User represents your internal user representation which extends Principal
        // UserService represents your internal user information source which extends PrincipalService
        final HeaderAuthBundle<User, UserService> headerAuthBundle =
            new HeaderAuthBundle<>(User.class, new UserService());
        
        bootstrap.addBundle(headerAuthBundle);
    }

    @Override
    public void run(SampleConfiguration configuration, Environment environment) {
        ...
    }
}

Inside your service's configuration yml file, add the header name that should be inspected:

authentication:
  headerName: USER_ID

And that's it! Any request that is sent to your service will inspect the header USER_ID and use this to return a single user and their roles from your UserService.