/*
 * Copyright 2020 The gRPC 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 io.grpc.internal;

import io.grpc.CallCredentials;
import io.grpc.Metadata;
import java.util.concurrent.Executor;

/**
 * CallCredentials that provides a single, fixed header.
 */
final class FakeCallCredentials extends CallCredentials {
  private final Metadata headers;

  public <T> FakeCallCredentials(Metadata.Key<T> key, T value) {
    headers = new Metadata();
    headers.put(key, value);
  }

  @Override
  public void applyRequestMetadata(
      CallCredentials.RequestInfo requestInfo,
      Executor appExecutor,
      CallCredentials.MetadataApplier applier) {
    applier.apply(headers);
  }

  @Override public void thisUsesUnstableApi() {}
}
