diff options
Diffstat (limited to 'kamon-core/src/main/scala/kamon/util')
-rw-r--r-- | kamon-core/src/main/scala/kamon/util/BaggageOnMDC.scala | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/kamon-core/src/main/scala/kamon/util/BaggageOnMDC.scala b/kamon-core/src/main/scala/kamon/util/BaggageOnMDC.scala new file mode 100644 index 00000000..885a73d9 --- /dev/null +++ b/kamon-core/src/main/scala/kamon/util/BaggageOnMDC.scala @@ -0,0 +1,72 @@ +/* + * ========================================================================================= + * Copyright © 2013-2015 the kamon project <http://kamon.io/> + * + * 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 kamon.util + +import java.util.function.Supplier + +import kamon.trace.{SpanContext => KamonSpanContext} +import kamon.Kamon +import org.slf4j.MDC + +import scala.collection.JavaConverters._ + +object BaggageOnMDC { + + /** + * Copy all baggage keys into SLF4J's MDC, evaluates the provided piece of code and removes the baggage keys + * afterwards, only when there is a currently active span. Optionally adds the Trace ID as well. + * + */ + def withBaggageOnMDC[T](includeTraceID: Boolean, code: => T): T = { + val activeSpan = Kamon.activeSpan() + if(activeSpan == null) + code + else { + val baggageItems = activeSpan.context().baggageItems().asScala + baggageItems.foreach(entry => MDC.put(entry.getKey, entry.getValue)) + if(includeTraceID) + addTraceIDToMDC(activeSpan.context()) + + val evaluatedCode = code + + baggageItems.foreach(entry => MDC.remove(entry.getKey)) + if(includeTraceID) + removeTraceIDFromMDC() + + evaluatedCode + + } + } + + def withBaggageOnMDC[T](code: Supplier[T]): T = + withBaggageOnMDC(true, code.get()) + + def withBaggageOnMDC[T](includeTraceID: Boolean, code: Supplier[T]): T = + withBaggageOnMDC(includeTraceID, code.get()) + + def withBaggageOnMDC[T](code: => T): T = + withBaggageOnMDC(true, code) + + private val TraceIDKey = "trace_id" + + private def addTraceIDToMDC(context: io.opentracing.SpanContext): Unit = context match { + case ctx: KamonSpanContext => MDC.put(TraceIDKey, HexCodec.toLowerHex(ctx.traceID)) + case _ => + } + + private def removeTraceIDFromMDC(): Unit = + MDC.remove(TraceIDKey) +} |