| /** |
| * 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 |
| * <p> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p> |
| * 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.hadoop.hdds.tracing; |
| |
| import java.lang.reflect.Proxy; |
| |
| import io.jaegertracing.Configuration; |
| import io.jaegertracing.internal.JaegerTracer; |
| import io.opentracing.Scope; |
| import io.opentracing.Span; |
| import io.opentracing.SpanContext; |
| import io.opentracing.Tracer; |
| import io.opentracing.util.GlobalTracer; |
| |
| import org.apache.hadoop.hdds.scm.ScmConfigKeys; |
| |
| /** |
| * Utility class to collect all the tracing helper methods. |
| */ |
| public final class TracingUtil { |
| |
| private static final String NULL_SPAN_AS_STRING = ""; |
| |
| private TracingUtil() { |
| } |
| |
| /** |
| * Initialize the tracing with the given service name. |
| * |
| * @param serviceName |
| */ |
| public static void initTracing(String serviceName) { |
| if (!GlobalTracer.isRegistered()) { |
| Configuration config = Configuration.fromEnv(serviceName); |
| JaegerTracer tracer = config.getTracerBuilder() |
| .registerExtractor(StringCodec.FORMAT, new StringCodec()) |
| .registerInjector(StringCodec.FORMAT, new StringCodec()) |
| .build(); |
| GlobalTracer.register(tracer); |
| } |
| } |
| |
| /** |
| * Export the active tracing span as a string. |
| * |
| * @return encoded tracing context. |
| */ |
| public static String exportCurrentSpan() { |
| if (GlobalTracer.get().activeSpan() != null) { |
| StringBuilder builder = new StringBuilder(); |
| GlobalTracer.get().inject(GlobalTracer.get().activeSpan().context(), |
| StringCodec.FORMAT, builder); |
| return builder.toString(); |
| } |
| return NULL_SPAN_AS_STRING; |
| } |
| |
| /** |
| * Export the specific span as a string. |
| * |
| * @return encoded tracing context. |
| */ |
| public static String exportSpan(Span span) { |
| if (span != null) { |
| StringBuilder builder = new StringBuilder(); |
| GlobalTracer.get().inject(span.context(), StringCodec.FORMAT, builder); |
| return builder.toString(); |
| } |
| return NULL_SPAN_AS_STRING; |
| } |
| |
| /** |
| * Create a new scope and use the imported span as the parent. |
| * |
| * @param name name of the newly created scope |
| * @param encodedParent Encoded parent span (could be null or empty) |
| * |
| * @return OpenTracing scope. |
| */ |
| public static Scope importAndCreateScope(String name, String encodedParent) { |
| Tracer.SpanBuilder spanBuilder; |
| Tracer tracer = GlobalTracer.get(); |
| SpanContext parentSpan = null; |
| if (encodedParent != null && encodedParent.length() > 0) { |
| StringBuilder builder = new StringBuilder(); |
| builder.append(encodedParent); |
| parentSpan = tracer.extract(StringCodec.FORMAT, builder); |
| |
| } |
| |
| if (parentSpan == null) { |
| spanBuilder = tracer.buildSpan(name); |
| } else { |
| spanBuilder = |
| tracer.buildSpan(name).asChildOf(parentSpan); |
| } |
| return spanBuilder.startActive(true); |
| } |
| |
| /** |
| * Creates a proxy of the implementation and trace all the method calls. |
| * |
| * @param delegate the original class instance |
| * @param interfce the interface which should be implemented by the proxy |
| * @param <T> the type of the interface |
| * @param conf configuration |
| * |
| * @return A new interface which implements interfce but delegate all the |
| * calls to the delegate and also enables tracing. |
| */ |
| public static <T> T createProxy(T delegate, Class<T> interfce, |
| org.apache.hadoop.conf.Configuration conf) { |
| boolean isTracingEnabled = conf.getBoolean( |
| ScmConfigKeys.HDDS_TRACING_ENABLED, |
| ScmConfigKeys.HDDS_TRACING_ENABLED_DEFAULT); |
| if (!isTracingEnabled) { |
| return delegate; |
| } |
| Class<?> aClass = delegate.getClass(); |
| return (T) Proxy.newProxyInstance(aClass.getClassLoader(), |
| new Class<?>[] {interfce}, |
| new TraceAllMethod<T>(delegate, interfce.getSimpleName())); |
| } |
| |
| } |