content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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 org.apache.beam.runners.dataflow.worker.windmill;
  
  import com.google.auto.value.AutoValue;
  import java.util.Optional;
  import java.util.function.Function;
  import java.util.function.Supplier;
  import org.apache.beam.runners.dataflow.worker.windmill.CloudWindmillServiceV1Alpha1Grpc.CloudWindmillServiceV1Alpha1Stub;
  import org.apache.beam.runners.dataflow.worker.windmill.WindmillEndpoints.Endpoint;
  import org.apache.beam.sdk.annotations.Internal;
  
  @AutoValue
  @Internal
  public abstract class WindmillConnection {
    private static final String NO_BACKEND_WORKER_TOKEN = "";
  
    public static WindmillConnection from(
        Endpoint windmillEndpoint,
        Function<Endpoint, CloudWindmillServiceV1Alpha1Stub> endpointToStubFn) {
      WindmillConnection.Builder windmillWorkerConnection = WindmillConnection.builder();
  
      windmillEndpoint.workerToken().ifPresent(windmillWorkerConnection::setBackendWorkerToken);
      windmillEndpoint.directEndpoint().ifPresent(windmillWorkerConnection::setDirectEndpoint);
      windmillWorkerConnection.setStubSupplier(() -> endpointToStubFn.apply(windmillEndpoint));
  
      return windmillWorkerConnection.build();
    }
  
    public static Builder builder() {
      return new AutoValue_WindmillConnection.Builder()
          .setBackendWorkerToken(NO_BACKEND_WORKER_TOKEN);
    }
  
    public abstract String backendWorkerToken();
  
    abstract Optional<WindmillServiceAddress> directEndpoint();
  
    abstract Supplier<CloudWindmillServiceV1Alpha1Stub> stubSupplier();
  
    public final CloudWindmillServiceV1Alpha1Stub currentStub() {
      return stubSupplier().get();
    }
  
    @AutoValue.Builder
    public abstract static class Builder {
      abstract Builder setBackendWorkerToken(String backendWorkerToken);
  
      abstract Builder setDirectEndpoint(WindmillServiceAddress value);
  
      public abstract Builder setStubSupplier(
          Supplier<CloudWindmillServiceV1Alpha1Stub> stubSupplier);
  
      public abstract WindmillConnection build();
    }
  }
  