sandeep-paliwal commented on a change in pull request #2282: Distributed tracing support #2192 URL: https://github.com/apache/incubator-openwhisk/pull/2282#discussion_r120846504
########## File path: common/scala/src/main/scala/whisk/common/tracing/TraceUtil.scala ########## @@ -0,0 +1,130 @@ +/* + * Copyright 2015-2016 IBM Corporation + * + * Licensed 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 java.util +import java.util.{HashMap, Map} +import java.util.concurrent.atomic.AtomicInteger + +import akka.actor.ActorSystem +import com.github.levkhomich.akka.tracing._ +import whisk.common.{LoggingMarkers, TransactionId} + +/** + * Trace Utility Class which provides all methods to trace a given service. + */ +object TraceUtil{ + + private lazy val trace: TracingExtensionImpl = traceVar; + + private var traceVar: TracingExtensionImpl = null; + + private val traceMap : Map[Long, TracedRequest] = new util.HashMap[Long, TracedRequest]() + + var requestCounter: AtomicInteger = new AtomicInteger(1); + + def init (actorSystem: ActorSystem): TracingExtensionImpl = { + + if(traceVar == null) + traceVar = TracingExtension.apply(actorSystem); + + return trace; + } + + /** + * Start a Trace for given service. + * @param serviceName Name of Service to be traced + * @param transactionId transactionId to which this Trace belongs. + * @return TracedRequest which provides details about current service being traced. + */ + def startTrace(serviceName: String, transactionId: TransactionId): Unit = { + var tracedRequest: TracedRequest = traceMap.get(transactionId.meta.id) + if(tracedRequest == null){ + var tracedRequest = createTracedRequest(serviceName) + var metadata = trace.sample(tracedRequest.getRequest(), serviceName) + if(metadata != None){ + trace.start(tracedRequest.getRequest(), serviceName) + tracedRequest = new TracedRequest(tracedRequest.getRequest(), null, metadata) + traceMap.put(transactionId.meta.id, tracedRequest) + } + } + else + startChildTrace(serviceName, tracedRequest, transactionId) + } + + /** + * Start a Child Trace + * @param serviceName Name of service to be traced + * @param parent Parent TracedRequest to continue span propagation and create span hierarchy. + * @param transactionId transactionId to which this Trace belongs. + * @return TracedRequest which provides details about current service being traced. + */ + def startChildTrace(serviceName: String, parent: TracedRequest, transactionId: TransactionId): Unit = { + val request: TracedRequest = createTracedRequest(serviceName) + var metadata = trace.sample(request.getRequest(), serviceName) + if(metadata != None){ + trace.createChild(request.getRequest(), parent.getRequest()) + trace.start(request.getRequest(), serviceName) + val tracedRequest = new TracedRequest(request.getRequest(), parent, metadata) + traceMap.put(transactionId.meta.id, tracedRequest) + } + + } + + /** + * Finish a Trace associated with given transactionId. + * @param transactionId + */ + def finish(transactionId: TransactionId): Unit = { + val request: TracedRequest = traceMap.get(transactionId.meta.id) + if(request != null){ + trace.record(request.getRequest(), TracingAnnotations.ServerSend) + if(request.getParent() == null) + traceMap.remove(transactionId.meta.id) + else + traceMap.put(transactionId.meta.id, request.getParent()) + } + } + + def error(transactionId: TransactionId, t: Throwable) : Unit = { + val request: TracedRequest = traceMap.get(transactionId.meta.id) + if(request != null){ + trace.record(request.getRequest(), t) + } + } + + private def createTracedRequest(serviceName: String, metadata: Option[SpanMetadata] = None) : TracedRequest = { + val headers: Map[String, Integer] = new HashMap[String, Integer] Review comment: I had tried this earlier but looks like Akka-tracing lib manages headers internally and I cannot specify them as you have mentioned. Propagation is controlled by `SpanMetadata` and this needs to be passed on to downstream services. Although `SpanMetadata` has same fields as B3-Propagation headers. ---------------------------------------------------------------- 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: [email protected] With regards, Apache Git Services
