| /** |
| * 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.camel.component.etcd; |
| |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.TimeoutException; |
| import java.util.concurrent.atomic.AtomicLong; |
| |
| import mousio.client.promises.ResponsePromise; |
| import mousio.etcd4j.requests.EtcdKeyGetRequest; |
| import mousio.etcd4j.responses.EtcdException; |
| import mousio.etcd4j.responses.EtcdKeysResponse; |
| import org.apache.camel.Exchange; |
| import org.apache.camel.Processor; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| public class EtcdWatchConsumer extends AbstractEtcdConsumer implements ResponsePromise.IsSimplePromiseResponseHandler<EtcdKeysResponse> { |
| private static final Logger LOGGER = LoggerFactory.getLogger(EtcdWatchConsumer.class); |
| |
| private final EtcdWatchEndpoint endpoint; |
| private final EtcdConfiguration configuration; |
| private final AtomicLong index; |
| |
| public EtcdWatchConsumer(EtcdWatchEndpoint endpoint, Processor processor, EtcdConfiguration configuration, EtcdNamespace namespace, String path) { |
| super(endpoint, processor, configuration, namespace, path); |
| |
| this.endpoint = endpoint; |
| this.configuration = configuration; |
| this.index = new AtomicLong(configuration.getFromIndex()); |
| } |
| |
| @Override |
| protected void doStart() throws Exception { |
| super.doStart(); |
| |
| watch(); |
| } |
| |
| @Override |
| protected void doStop() throws Exception { |
| super.doStop(); |
| } |
| |
| @Override |
| public void onResponse(ResponsePromise<EtcdKeysResponse> promise) { |
| if (!isRunAllowed()) { |
| return; |
| } |
| |
| Exchange exchange = null; |
| Throwable throwable = promise.getException(); |
| |
| if (throwable instanceof EtcdException) { |
| EtcdException exception = (EtcdException) throwable; |
| // Etcd only keeps the responses of the most recent 1000 events |
| // across all etcd keys so if we wait for a cleared index, we |
| // get "index is outdated response" like: |
| // |
| // { |
| // "errorCode" : 401, |
| // "message" : "The event in requested index is outdated and cleared", |
| // "cause" : "the requested history has been cleared [1008/8]", |
| // "index" : 2007 |
| // } |
| // |
| // So we set the index to the one returned by the exception + 1 |
| if (EtcdHelper.isOutdatedIndexException(exception)) { |
| LOGGER.debug("Outdated index, key: {}, cause={}", getPath(), exception.etcdCause); |
| |
| // We set the index to the one returned by the exception + 1. |
| index.set(exception.index + 1); |
| |
| // Clean-up the exception so it is not rethrown/handled |
| throwable = null; |
| } |
| } else { |
| try { |
| EtcdKeysResponse response = promise.get(); |
| |
| exchange = endpoint.createExchange(); |
| exchange.getIn().setHeader(EtcdConstants.ETCD_NAMESPACE, getNamespace()); |
| exchange.getIn().setHeader(EtcdConstants.ETCD_PATH, response.node.key); |
| exchange.getIn().setBody(response); |
| |
| // Watch from the modifiedIndex + 1 of the node we got for ensuring |
| // no events are missed between watch commands |
| index.set(response.node.modifiedIndex + 1); |
| } catch (TimeoutException e) { |
| LOGGER.debug("Timeout watching for {}", getPath()); |
| |
| if (configuration.isSendEmptyExchangeOnTimeout()) { |
| exchange = endpoint.createExchange(); |
| exchange.getIn().setHeader(EtcdConstants.ETCD_NAMESPACE, getNamespace()); |
| exchange.getIn().setHeader(EtcdConstants.ETCD_TIMEOUT, true); |
| exchange.getIn().setHeader(EtcdConstants.ETCD_PATH, getPath()); |
| exchange.getIn().setBody(null); |
| } |
| |
| throwable = null; |
| } catch (Exception e1) { |
| throwable = e1; |
| } |
| |
| if (exchange != null) { |
| try { |
| throwable = null; |
| getProcessor().process(exchange); |
| } catch (Exception e) { |
| getExceptionHandler().handleException("Error processing exchange", exchange, e); |
| } |
| } |
| } |
| |
| if (throwable != null) { |
| handleException("Error processing etcd response", throwable); |
| } |
| |
| try { |
| watch(); |
| } catch (Exception e) { |
| handleException("Error watching key " + getPath(), e); |
| } |
| } |
| |
| private void watch() throws Exception { |
| if (!isRunAllowed()) { |
| return; |
| } |
| |
| EtcdKeyGetRequest request = getClient().get(getPath()).waitForChange(index.get()); |
| if (configuration.isRecursive()) { |
| request.recursive(); |
| } |
| if (configuration.getTimeout() != null) { |
| request.timeout(configuration.getTimeout(), TimeUnit.MILLISECONDS); |
| } |
| |
| request.send().addListener(this); |
| } |
| } |