code: /*
   * 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.skywalking.oap.server.receiver.log.provider.handler.grpc;
  
  import io.grpc.stub.StreamObserver;
  import lombok.extern.slf4j.Slf4j;
  import org.apache.skywalking.apm.network.common.v3.Commands;
  import org.apache.skywalking.apm.network.logging.v3.LogData;
  import org.apache.skywalking.apm.network.logging.v3.LogReportServiceGrpc;
  import org.apache.skywalking.oap.server.library.util.StringUtil;
  import org.apache.skywalking.oap.log.analyzer.module.LogAnalyzerModule;
  import org.apache.skywalking.oap.log.analyzer.provider.log.ILogAnalyzerService;
  import org.apache.skywalking.oap.server.library.module.ModuleManager;
  import org.apache.skywalking.oap.server.library.server.grpc.GRPCHandler;
  import org.apache.skywalking.oap.server.telemetry.TelemetryModule;
  import org.apache.skywalking.oap.server.telemetry.api.CounterMetrics;
  import org.apache.skywalking.oap.server.telemetry.api.HistogramMetrics;
  import org.apache.skywalking.oap.server.telemetry.api.MetricsCreator;
  import org.apache.skywalking.oap.server.telemetry.api.MetricsTag;
  
  /**
   * Collect log data
   */
  @Slf4j
  public class LogReportServiceGrpcHandler extends LogReportServiceGrpc.LogReportServiceImplBase implements GRPCHandler {
  
      private final HistogramMetrics histogram;
      private final CounterMetrics errorCounter;
      private final ILogAnalyzerService logAnalyzerService;
  
      public LogReportServiceGrpcHandler(final ModuleManager moduleManager) {
          MetricsCreator metricsCreator = moduleManager.find(TelemetryModule.NAME)
                                                       .provider()
                                                       .getService(MetricsCreator.class);
          this.logAnalyzerService = moduleManager.find(LogAnalyzerModule.NAME)
                                                 .provider()
                                                 .getService(ILogAnalyzerService.class);
  
          histogram = metricsCreator.createHistogramMetric(
              "log_in_latency", "The process latency of log",
              new MetricsTag.Keys("protocol"), new MetricsTag.Values("grpc")
          );
          errorCounter = metricsCreator.createCounter("log_analysis_error_count", "The error number of log analysis",
                                                      new MetricsTag.Keys("protocol"), new MetricsTag.Values("grpc")
          );
      }
  
      @Override
      public StreamObserver<LogData> collect(final StreamObserver<Commands> responseObserver) {
          return new StreamObserver<LogData>() {
  
              private String serviceName;
  
              /**
               * If this is not the first element of the streaming,
               * use the previous not-null name as the service name.
               */
              private void setServiceName(LogData.Builder builder) {
                  if (StringUtil.isEmpty(serviceName) && StringUtil.isNotEmpty(builder.getService())) {
                      serviceName = builder.getService();
                  } else if (StringUtil.isNotEmpty(serviceName)) {
                      builder.setService(serviceName);
                  }
              }
  
              @Override
              public void onNext(final LogData logData) {
                  if (log.isDebugEnabled()) {
                      log.debug("received log in streaming");
                  }
                  HistogramMetrics.Timer timer = histogram.createTimer();
                  try {
                      LogData.Builder builder = logData.toBuilder();
                      setServiceName(builder);
                      logAnalyzerService.doAnalysis(builder, null);
                  } catch (Exception e) {
                      errorCounter.inc();
                      log.error(e.getMessage(), e);
                  } finally {
                      timer.finish();
                  }
              }
  
              @Override
              public void onError(final Throwable throwable) {
                  log.error(throwable.getMessage(), throwable);
              }
  
              @Override
              public void onCompleted() {
                  responseObserver.onNext(Commands.newBuilder().build());
                  responseObserver.onCompleted();
              }
          };
      }
  }
  