IterablePromisePublisher.java

/*
 * Copyright 2015 the original author or authors.
 *
 * 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.
 */

package ratpack.stream.internal;

import org.reactivestreams.Subscriber;
import ratpack.exec.Promise;
import ratpack.stream.Streams;
import ratpack.stream.TransformablePublisher;

public class IterablePromisePublisher<T> implements TransformablePublisher<T> {

  private final Promise<? extends Iterable<? extends T>> promise;

  public IterablePromisePublisher(Promise<? extends Iterable<? extends T>> promise) {
    this.promise = promise;
  }

  @Override
  public void subscribe(Subscriber<? super T> subscriber) {
    this.promise.onError(subscriber::onError).then(i ->
        Streams.publish(i).subscribe(subscriber)
    );
  }

}