| /* |
| * 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.htrace.impl; |
| |
| import java.io.IOException; |
| import java.nio.charset.Charset; |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.concurrent.ArrayBlockingQueue; |
| import java.util.concurrent.BlockingQueue; |
| import java.util.concurrent.ExecutorService; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.ThreadFactory; |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| import java.util.concurrent.atomic.AtomicLong; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.flume.Event; |
| import org.apache.flume.FlumeException; |
| import org.apache.flume.api.RpcClient; |
| import org.apache.flume.api.RpcClientFactory; |
| import org.apache.flume.event.EventBuilder; |
| import org.apache.htrace.core.HTraceConfiguration; |
| import org.apache.htrace.core.Span; |
| import org.apache.htrace.core.SpanReceiver; |
| import org.apache.htrace.core.TracerId; |
| |
| public class FlumeSpanReceiver extends SpanReceiver { |
| private static final Log LOG = LogFactory.getLog(FlumeSpanReceiver.class); |
| |
| public static final String NUM_THREADS_KEY = "htrace.flume.num-threads"; |
| public static final int DEFAULT_NUM_THREADS = 1; |
| public static final String FLUME_HOSTNAME_KEY = "htrace.flume.hostname"; |
| public static final String DEFAULT_FLUME_HOSTNAME = "localhost"; |
| public static final String FLUME_PORT_KEY = "htrace.flume.port"; |
| public static final String FLUME_BATCHSIZE_KEY = "htrace.flume.batchsize"; |
| public static final int DEFAULT_FLUME_BATCHSIZE = 100; |
| |
| /** |
| * How long this receiver will try and wait for all threads to shutdown. |
| */ |
| private static final int SHUTDOWN_TIMEOUT = 30; |
| |
| /** |
| * How many errors in a row before we start dropping traces on the floor. |
| */ |
| private static final int MAX_ERRORS = 10; |
| |
| /** |
| * The queue that will get all HTrace spans that are to be sent. |
| */ |
| private final BlockingQueue<Span> queue; |
| |
| /** |
| * Boolean used to signal that the threads should end. |
| */ |
| private final AtomicBoolean running = new AtomicBoolean(true); |
| |
| /** |
| * The thread factory used to create new ExecutorService. |
| * <p/> |
| * This will be the same factory for the lifetime of this object so that |
| * no thread names will ever be duplicated. |
| */ |
| private final ThreadFactory tf; |
| |
| //////////////////// |
| /// Variables that will change on each call to configure() |
| /////////////////// |
| private ExecutorService service; |
| private int maxSpanBatchSize; |
| private String flumeHostName; |
| private int flumePort; |
| |
| public FlumeSpanReceiver(HTraceConfiguration conf) { |
| this.queue = new ArrayBlockingQueue<Span>(1000); |
| this.tf = new SimpleThreadFactory(); |
| configure(conf); |
| } |
| |
| private class SimpleThreadFactory implements ThreadFactory { |
| final AtomicLong count = new AtomicLong(0); |
| @Override |
| public Thread newThread(Runnable arg0) { |
| String name = String.format("flumeSpanReceiver-%d", count.getAndIncrement()); |
| Thread t = new Thread(arg0, name); |
| t.setDaemon(true); |
| return t; |
| } |
| } |
| |
| private void configure (HTraceConfiguration conf) { |
| |
| // Read configuration |
| int numThreads = conf.getInt(NUM_THREADS_KEY, DEFAULT_NUM_THREADS); |
| this.flumeHostName = conf.get(FLUME_HOSTNAME_KEY, DEFAULT_FLUME_HOSTNAME); |
| this.flumePort = conf.getInt(FLUME_PORT_KEY, 0); |
| if (this.flumePort == 0) { |
| throw new IllegalArgumentException(FLUME_PORT_KEY + " is required in configuration."); |
| } |
| this.maxSpanBatchSize = conf.getInt(FLUME_BATCHSIZE_KEY, DEFAULT_FLUME_BATCHSIZE); |
| |
| // Initialize executors |
| // If there are already threads running tear them down. |
| if (this.service != null) { |
| this.service.shutdownNow(); |
| this.service = null; |
| } |
| this.service = Executors.newFixedThreadPool(numThreads, tf); |
| for (int i = 0; i < numThreads; i++) { |
| this.service.submit(new WriteSpanRunnable()); |
| } |
| } |
| |
| private class WriteSpanRunnable implements Runnable { |
| private RpcClient flumeClient = null; |
| |
| /** |
| * This runnable sends a HTrace span to the Flume. |
| */ |
| @Override |
| public void run() { |
| List<Span> dequeuedSpans = new ArrayList<Span>(maxSpanBatchSize); |
| long errorCount = 0; |
| |
| while (running.get() || queue.size() > 0) { |
| Span firstSpan = null; |
| try { |
| // Block for up to a second. to try and get a span. |
| // We only block for a little bit in order to notice |
| // if the running value has changed |
| firstSpan = queue.poll(1, TimeUnit.SECONDS); |
| |
| // If the poll was successful then it's possible that there |
| // will be other spans to get. Try and get them. |
| if (firstSpan != null) { |
| // Add the first one that we got |
| dequeuedSpans.add(firstSpan); |
| // Try and get up to 100 queues |
| queue.drainTo(dequeuedSpans, maxSpanBatchSize - 1); |
| } |
| } catch (InterruptedException ie) { |
| // Ignored. |
| } |
| |
| startClient(); |
| if (dequeuedSpans.isEmpty()) { |
| continue; |
| } |
| |
| try { |
| List<Event> events = new ArrayList<Event>(dequeuedSpans.size()); |
| for (Span span : dequeuedSpans) { |
| // Headers allow Flume to filter |
| Map<String, String> headers = new HashMap<String, String>(); |
| headers.put("SpanId", span.toString()); |
| headers.put("TracerId", span.getTracerId()); |
| headers.put("Description", span.getDescription()); |
| |
| String body = span.toJson(); |
| |
| Event evt = EventBuilder.withBody(body, Charset.forName("UTF-8"), headers); |
| events.add(evt); |
| } |
| flumeClient.appendBatch(events); |
| |
| // clear the list for the next time through. |
| dequeuedSpans.clear(); |
| // reset the error counter. |
| errorCount = 0; |
| } catch (Exception e) { |
| errorCount += 1; |
| // If there have been ten errors in a row start dropping things. |
| if (errorCount < MAX_ERRORS) { |
| try { |
| queue.addAll(dequeuedSpans); |
| } catch (IllegalStateException ex) { |
| LOG.error("Drop " + dequeuedSpans.size() + |
| " span(s) because writing to HBase failed."); |
| } |
| } |
| closeClient(); |
| try { |
| // Since there was an error sleep just a little bit to try and allow the |
| // HBase some time to recover. |
| Thread.sleep(500); |
| } catch (InterruptedException e1) { |
| // Ignored |
| } |
| } |
| } |
| closeClient(); |
| } |
| |
| /** |
| * Close Flume RPC client |
| */ |
| private void closeClient() { |
| if (flumeClient != null) { |
| try { |
| flumeClient.close(); |
| } catch (FlumeException ex) { |
| LOG.warn("Error while trying to close Flume Rpc Client.", ex); |
| } finally { |
| flumeClient = null; |
| } |
| } |
| } |
| |
| /** |
| * Create / reconnect Flume RPC client |
| */ |
| private void startClient() { |
| // If current client is inactive, close it |
| if (flumeClient != null && !flumeClient.isActive()) { |
| flumeClient.close(); |
| flumeClient = null; |
| } |
| // Create client if needed |
| if (flumeClient == null) { |
| try { |
| flumeClient = RpcClientFactory.getDefaultInstance(flumeHostName, flumePort, maxSpanBatchSize); |
| } catch (FlumeException e) { |
| LOG.warn("Failed to create Flume RPC Client. " + e.getMessage()); |
| } |
| } |
| } |
| } |
| |
| /** |
| * Close the receiver and shut down the thread pool. |
| * |
| * @throws IOException On error. |
| */ |
| @Override |
| public void close() throws IOException { |
| running.set(false); |
| service.shutdown(); |
| try { |
| if (!service.awaitTermination(SHUTDOWN_TIMEOUT, TimeUnit.SECONDS)) { |
| LOG.error("Was not able to process all remaining spans upon closing in: " + |
| SHUTDOWN_TIMEOUT + " " + TimeUnit.SECONDS + |
| ". Left Spans could be dropped."); |
| } |
| } catch (InterruptedException e1) { |
| LOG.warn("Thread interrupted when terminating executor.", e1); |
| } |
| } |
| |
| @Override |
| public void receiveSpan(Span span) { |
| if (running.get()) { |
| try { |
| this.queue.add(span); |
| } catch (IllegalStateException e) { |
| LOG.error("Error trying to append span (" + |
| span.getDescription() + |
| ") to the queue. Blocking Queue was full."); |
| } |
| } |
| } |
| } |