chetanmeh commented on a change in pull request #2282: Distributed tracing support #2192 URL: https://github.com/apache/incubator-openwhisk/pull/2282#discussion_r194664618
########## File path: common/scala/src/main/scala/whisk/common/tracing/OpenTracingProvider.scala ########## @@ -0,0 +1,220 @@ +/* + * 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 whisk.common.tracing + +import scala.collection.mutable +import scala.collection.JavaConverters._ +import brave.Tracing +import brave.opentracing.BraveTracer +import brave.sampler.Sampler +import io.opentracing.{Span, SpanContext, Tracer} +import io.opentracing.util.GlobalTracer +import io.opentracing.propagation.{Format, TextMapExtractAdapter, TextMapInjectAdapter} +import zipkin2.reporter.{AsyncReporter, Sender} +import zipkin2.reporter.okhttp3.OkHttpSender +import pureconfig._ +import whisk.common.{LogMarkerToken, TransactionId} +import whisk.core.ConfigKeys + +import scala.ref.WeakReference + +/** + * OpenTracing based implementation for tracing + */ +class OpenTracer(val tracer: Tracer) extends WhiskTracer { + + /** + * Start a Trace for given service. + * + * @param transactionId transactionId to which this Trace belongs. + * @return TracedRequest which provides details about current service being traced. + */ + override def startSpan(logMarker: LogMarkerToken, transactionId: TransactionId): Unit = { + + val activeSpan: Option[Span] = + TracingCacheProvider.spanCache.get(transactionId.meta.id) match { + case Some(spanList) => { + //create a child span + val spanBuilder = tracer + .buildSpan(logMarker.action) + .withTag("transactionId", transactionId.meta.id) + + Some( + spanList.last.get + .map(spanBuilder.asChildOf(_).startActive(true).span()) + .getOrElse(spanBuilder.startActive(true).span())) + + } + case None => { + //initialize list for this transactionId + val list: mutable.ListBuffer[WeakReference[Span]] = mutable.ListBuffer() + TracingCacheProvider.spanCache.put(transactionId.meta.id, list) + + TracingCacheProvider.contextCache.get(transactionId.meta.id) match { + case Some(context) => { + //create child span if we have a tracing context + Some( + tracer + .buildSpan(logMarker.action) + .withTag("transactionId", transactionId.meta.id) + .asChildOf(context) + .startActive(true) + .span()) + } + case None => { + Some( + tracer + .buildSpan(logMarker.action) + .ignoreActiveSpan() + .withTag("transactionId", transactionId.meta.id) + .startActive(true) + .span()) + } + } + } + } + + //add active span to list + if (activeSpan.isDefined) + TracingCacheProvider.spanCache.get(transactionId.meta.id).map(_.+=:(new WeakReference(activeSpan.get))) + } + + /** + * Finish a Trace associated with given transactionId. + * + * @param transactionId + */ + override def finishSpan(transactionId: TransactionId): Unit = { + clear(transactionId) + } + + /** + * Register error + * + * @param transactionId + */ + override def error(transactionId: TransactionId): Unit = { + clear(transactionId) + } + + /** + * Get the current TraceContext which can be used for downstream services + * + * @param transactionId + * @return + */ + override def getTraceContext(transactionId: TransactionId): Option[Map[String, String]] = { + var contextMap: Option[Map[String, String]] = None + TracingCacheProvider.spanCache.get(transactionId.meta.id) match { + case Some(spanList) => { + var map: java.util.Map[String, String] = new java.util.HashMap() + //inject latest span context in map + spanList.last.get match { + case Some(span) => { + tracer.inject(span.context(), Format.Builtin.TEXT_MAP, new TextMapInjectAdapter(map)) + contextMap = Some(map.asScala.toMap) + } + case _ => + } + } + case None => None + } + contextMap + } + + /** + * Get the current TraceContext which can be used for downstream services + * + * @param transactionId + * @return + */ + override def setTraceContext(transactionId: TransactionId, context: Option[Map[String, String]]) = { + context match { + case Some(scalaMap) => { + var javaMap: java.util.Map[String, String] = + scala.collection.JavaConverters.mapAsJavaMapConverter(scalaMap).asJava + var ctx: SpanContext = tracer.extract(Format.Builtin.TEXT_MAP, new TextMapExtractAdapter(javaMap)) + TracingCacheProvider.contextCache.put(transactionId.meta.id, ctx) + } + case None => + } + } + + private def clear(transactionId: TransactionId): Unit = { + TracingCacheProvider.spanCache.get(transactionId.meta.id) match { + case Some(spanList) => { + spanList.last.get.map(_.finish) + spanList.remove(spanList.size - 1) + if (spanList.isEmpty) { + TracingCacheProvider.spanCache.invalidate(transactionId.meta.id) + TracingCacheProvider.contextCache.invalidate(transactionId.meta.id) + } + + } + case None => + } + } +} + +trait WhiskTracer { + def startSpan(logMarker: LogMarkerToken, transactionId: TransactionId): Unit = {} + def finishSpan(transactionId: TransactionId): Unit = {} + def error(transactionId: TransactionId): Unit = {} + def getTraceContext(transactionId: TransactionId): Option[Map[String, String]] = None + def setTraceContext(transactionId: TransactionId, context: Option[Map[String, String]]): Unit = {} +} + +object WhiskTracerProvider { + val tracingConfig = loadConfigOrThrow[TracingConfig](ConfigKeys.tracing) + + val tracer: WhiskTracer = createTracer(tracingConfig) + + private def createTracer(tracingConfig: TracingConfig): WhiskTracer = { + + tracingConfig.zipkin match { + case Some(zipkinConfig) => { + val zipkinConfig = tracingConfig.zipkin.get + if (!GlobalTracer.isRegistered) { + val sender: Sender = OkHttpSender.create(zipkinConfig.getUrl) + val spanReporter = AsyncReporter.create(sender) + val braveTracing = Tracing + .newBuilder() + .localServiceName(tracingConfig.component) + .spanReporter(spanReporter) + .sampler(Sampler.create(zipkinConfig.sampleRate.toFloat)) + .build(); + + //register with OpenTracing + GlobalTracer.register(BraveTracer.create(braveTracing)) + } + } + case None => + } + + if (GlobalTracer.isRegistered) + new OpenTracer(GlobalTracer.get()) + else + NoopTracer + } +} + +private object NoopTracer extends WhiskTracer +case class TracingConfig(component: String, cacheExpiry: Option[Int] = None, zipkin: Option[ZipkinConfig] = None) Review comment: Instead of using `Option[Int]` prefer using `Duration` then config can have values like `1 minute`. No need for making it `Option` as default value is specified in `application.conf`. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
