modeldb-main/backend/server/src/main/java/ai/verta/modeldb/health/HealthStatusManager.java
/*
 * Copyright 2016 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.
 *
 * Modified class io.grpc.services.HealthStatusManager
 * Verta changes: use custom health service
 */

package ai.verta.modeldb.health;

import static com.google.common.base.Preconditions.checkNotNull;

import io.grpc.BindableService;
import io.grpc.health.v1.HealthCheckResponse.ServingStatus;

/**
 * A {@code HealthStatusManager} object manages a health check service. A health check service is
 * created in the constructor of {@code HealthStatusManager}, and it can be retrieved by the {@link
 * #getHealthService()} method. The health status manager can update the health statuses of the
 * server.
 */
public class HealthStatusManager {

  private final HealthServiceImpl healthService;

  /** Creates a new health service instance. */
  public HealthStatusManager(HealthServiceImpl healthService) {
    this.healthService = healthService;
  }

  /** Gets the health check service created in the constructor. */
  public BindableService getHealthService() {
    return healthService;
  }

  /**
   * Updates the status of the server.
   *
   * @param service the name of some aspect of the server that is associated with a health status.
   *     This name can have no relation with the gRPC services that the server is running with. It
   *     can also be an empty String {@code ""} per the gRPC specification.
   * @param status is one of the values {@link ServingStatus#SERVING}, {@link
   *     ServingStatus#NOT_SERVING} and {@link ServingStatus#UNKNOWN}.
   */
  public void setStatus(String service, ServingStatus status) {
    checkNotNull(status, "status");
    healthService.setStatus(service, status);
  }

  /**
   * Clears the health status record of a service. The health service will respond with NOT_FOUND
   * error on checking the status of a cleared service.
   *
   * @param service the name of some aspect of the server that is associated with a health status.
   *     This name can have no relation with the gRPC services that the server is running with. It
   *     can also be an empty String {@code ""} per the gRPC specification.
   */
  public void clearStatus(String service) {
    healthService.clearStatus(service);
  }
}
