public interface ApplicationContext<T extends Config> {
  T getConfig();
}

public interface Application<T extends Config> {
  void configure(ApplicationConfigurer configurer, ApplicationContext<T> context);
}
 
public abstract class AbstractApplication<T> implements Application<T extends Config> {
  ...
  protected final ApplicationContext<T> getContext() { return context; }
}
 
public class MyApp extends AbstractApplication<MyApp.MyConfig> {
 
  public static class MyConfig extends Config {
    @Nullable
    private String stream;
 
    @Nullable
    private String table;
    private MyFlowConfig flowOptions;
 
    private MyConfig() {
      this.stream = "A";
      this.table = "X";
    }
  }
 
  public void configure() {
    // ApplicationContext now has a method to get a custom config object whose fields will
    // be injected using the values given in the RESTful API
    MyConfig config = getContext().getConfig();
    addStream(new Stream(config.stream));
    createDataset(config.table, Table.class);
    addFlow(new MyFlow(config.stream, config.table, config.flowOptions));
  }
}

PUT /namespaces/default/apps/myapp2 -H "Content-Type: application/json" -d '{ "artifact": { "name": "myapp", "version": "1.0.0" }, "config": { "stream": "B", "table": "X" } }'

PUT /namespaces/default/apps/myapp3 -H "Content-Type: application/json" -d '{ "artifact": { "name": "my-app", "version": "1.0.1" }, "config": {"stream": "C", "table": "X"} }'

PUT /namespaces/default/apps/myapp/properties -H "Content-Type: application/json" -d '{ "artifact": { "name":"myapp", "version":"1.0.1" }, "config": { "stream": "A", "table": "X" } }'

PUT /namespaces/default/apps/somePipeline -H "Content-Type: application/json" -d '{ "artifact": { "namespace": "system", "name":"ETLBatch", "version":"3.1.0" }, "config": { ... } }'