content: /*
   * Copyright 2024-2025 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
   *
   *      https://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 com.alibaba.cloud.ai.graph.observation.node;
  
  import com.alibaba.cloud.ai.graph.observation.GraphMetricsGenerator;
  import io.micrometer.core.instrument.MeterRegistry;
  import io.micrometer.observation.Observation;
  import io.micrometer.observation.ObservationHandler;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Handler for graph node observation events. Processes node observation lifecycle events
   * and generates metrics for node operations. Logs node execution details and delegates
   * metric generation to GraphMetricsGenerator.
   *
   * @author XiaoYunTao
   * @since 2025/6/28
   */
  public class GraphNodeObservationHandler implements ObservationHandler<GraphNodeObservationContext> {
  
  	private static final Logger logger = LoggerFactory.getLogger(GraphNodeObservationHandler.class);
  
  	private final MeterRegistry meterRegistry;
  
  	/**
  	 * Constructs a new GraphNodeObservationHandler with the specified meter registry.
  	 * @param meterRegistry the meter registry for metric collection
  	 */
  	public GraphNodeObservationHandler(MeterRegistry meterRegistry) {
  		this.meterRegistry = meterRegistry;
  	}
  
  	/**
  	 * Handles the completion of a graph node observation. Logs successful node execution
  	 * details and generates success metrics.
  	 * @param context the node observation context containing execution details
  	 */
  	@Override
  	public void onStop(GraphNodeObservationContext context) {
  		GraphMetricsGenerator.generate(context, meterRegistry, true);
  	}
  
  	/**
  	 * Handles errors during graph node observation. Logs error details and generates
  	 * failure metrics.
  	 * @param context the node observation context containing error details
  	 */
  	@Override
  	public void onError(GraphNodeObservationContext context) {
  		GraphMetricsGenerator.generate(context, meterRegistry, false);
  	}
  
  	/**
  	 * Determines if this handler supports the given observation context. Returns true if
  	 * the context is an instance of GraphNodeObservationContext.
  	 * @param context the observation context to check
  	 * @return true if this handler supports the context, false otherwise
  	 */
  	@Override
  	public boolean supportsContext(Observation.Context context) {
  		return context instanceof GraphNodeObservationContext;
  	}
  
  }
  