| /* |
| * 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.servicecomb.bizkeeper; |
| |
| import org.apache.servicecomb.core.Const; |
| import org.apache.servicecomb.core.Invocation; |
| import org.apache.servicecomb.swagger.invocation.Response; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.netflix.config.DynamicPropertyFactory; |
| import com.netflix.hystrix.HystrixObservableCommand; |
| import com.netflix.hystrix.strategy.concurrency.HystrixRequestContext; |
| |
| import rx.Observable; |
| |
| /** |
| * 接管调用链的处理流程,处理完成后,将结果交给调用链。额外还提供了请求缓存的功能和容错/降级处理能力。 |
| * |
| */ |
| public abstract class BizkeeperCommand extends HystrixObservableCommand<Response> { |
| private static final Logger LOG = LoggerFactory.getLogger(BizkeeperCommand.class); |
| |
| private final Invocation invocation; |
| |
| private final String type; |
| |
| protected BizkeeperCommand(String type, Invocation invocation, HystrixObservableCommand.Setter setter) { |
| super(setter); |
| this.type = type; |
| this.invocation = invocation; |
| } |
| |
| @Override |
| protected String getCacheKey() { |
| if (HystrixRequestContext.isCurrentThreadInitialized()) { |
| StringBuilder sb = new StringBuilder(); |
| sb.append(this.getCommandGroup().name()); |
| sb.append("-"); |
| sb.append(this.getCommandKey().name()); |
| return sb.toString(); |
| } else { |
| return super.getCacheKey(); |
| } |
| } |
| |
| @Override |
| protected Observable<Response> resumeWithFallback() { |
| Throwable cause = getFailedExecutionException(); |
| Observable<Response> observable = Observable.create(f -> { |
| try { |
| f.onNext(FallbackPolicyManager.getFallbackResponse(type, cause, invocation)); |
| f.onCompleted(); |
| } catch (Exception e) { |
| if (DynamicPropertyFactory.getInstance().getBooleanProperty(Const.PRINT_SENSITIVE_ERROR_MESSAGE, |
| false).get()) { |
| LOG.warn("fallback failed.", e); |
| } else { |
| LOG.warn("fallback failed due to: {}", e.getMessage()); |
| } |
| throw e; |
| } |
| }); |
| return observable; |
| } |
| |
| @Override |
| protected Observable<Response> construct() { |
| Observable<Response> observable = Observable.create(f -> { |
| try { |
| invocation.next(resp -> { |
| if (isFailedResponse(resp)) { |
| LOG.warn("bizkeeper command {} failed, trace id {} result {}", |
| invocation.getInvocationQualifiedName(), |
| invocation.getTraceId(), |
| resp.getResult()); |
| f.onError(resp.getResult()); |
| FallbackPolicyManager.record(type, invocation, resp, false); |
| } else { |
| f.onNext(resp); |
| f.onCompleted(); |
| FallbackPolicyManager.record(type, invocation, resp, true); |
| } |
| }); |
| } catch (Exception e) { |
| LOG.warn("bizkeeper command {} execute failed, trace id {}, cause {}", |
| invocation.getInvocationQualifiedName(), |
| invocation.getTraceId(), |
| e.getClass().getName()); |
| f.onError(e); |
| } |
| }); |
| return observable; |
| } |
| |
| protected abstract boolean isFailedResponse(Response resp); |
| } |