package kamon.trace
import java.util.concurrent.ThreadLocalRandom
import com.typesafe.scalalogging.Logger
import io.opentracing.propagation.{TextMap, Format}
import io.opentracing.propagation.Format.Builtin.{BINARY, HTTP_HEADERS, TEXT_MAP}
import io.opentracing.util.ThreadLocalActiveSpanSource
import kamon.ReporterRegistryImpl
import kamon.util.Clock
class Tracer(metrics: Any, reporterRegistry: ReporterRegistryImpl) extends io.opentracing.Tracer {
private val logger = Logger(classOf[Tracer])
///private val metricsRecorder = new TracerMetricsRecorder(metrics.getRecorder(Entity("tracer", "tracer", Map.empty)))
private val activeSpanSource = new ThreadLocalActiveSpanSource()
@volatile private var sampler: Sampler = Sampler.never
@volatile private var textMapSpanContextCodec = SpanContextCodec.TextMap
@volatile private var httpHeaderSpanContextCodec = SpanContextCodec.ZipkinB3
override def buildSpan(operationName: String): io.opentracing.Tracer.SpanBuilder =
new SpanBuilder(operationName)
override def extract[C](format: Format[C], carrier: C): io.opentracing.SpanContext = format match {
case HTTP_HEADERS => httpHeaderSpanContextCodec.extract(carrier.asInstanceOf[TextMap], sampler)
case TEXT_MAP => textMapSpanContextCodec.extract(carrier.asInstanceOf[TextMap], sampler)
case BINARY => null // TODO: Implement Binary Encoding
case _ => null
}
override def inject[C](spanContext: io.opentracing.SpanContext, format: Format[C], carrier: C): Unit = format match {
case HTTP_HEADERS => httpHeaderSpanContextCodec.inject(spanContext.asInstanceOf[SpanContext], carrier.asInstanceOf[TextMap])
case TEXT_MAP => textMapSpanContextCodec.inject(spanContext.asInstanceOf[SpanContext], carrier.asInstanceOf[TextMap])
case BINARY =>
case _ =>
}
override def activeSpan(): io.opentracing.ActiveSpan =
activeSpanSource.activeSpan()
override def makeActive(span: io.opentracing.Span): io.opentracing.ActiveSpan =
activeSpanSource.makeActive(span)
def setTextMapSpanContextCodec(codec: SpanContextCodec[TextMap]): Unit =
this.textMapSpanContextCodec = codec
def setHttpHeaderSpanContextCodec(codec: SpanContextCodec[TextMap]): Unit =
this.httpHeaderSpanContextCodec = codec
private class SpanBuilder(operationName: String) extends io.opentracing.Tracer.SpanBuilder {
private var parentContext: SpanContext = _
private var startTimestamp = 0L
private var initialTags = Map.empty[String, String]
private var useActiveSpanAsParent = true
override def asChildOf(parent: io.opentracing.SpanContext): io.opentracing.Tracer.SpanBuilder = parent match {
case spanContext: kamon.trace.SpanContext =>
this.parentContext = spanContext
this
case _ => logger.error("Can't extract the parent ID from a non-Kamon SpanContext"); this
}
override def asChildOf(parent: io.opentracing.BaseSpan[_]): io.opentracing.Tracer.SpanBuilder =
asChildOf(parent.context())
override def addReference(referenceType: String, referencedContext: io.opentracing.SpanContext): io.opentracing.Tracer.SpanBuilder = {
if(referenceType != null && referenceType.equals(io.opentracing.References.CHILD_OF)) {
asChildOf(referencedContext)
} else this
}
override def withTag(key: String, value: String): io.opentracing.Tracer.SpanBuilder = {
this.initialTags = this.initialTags + (key -> value)
this
}
override def withTag(key: String, value: Boolean): io.opentracing.Tracer.SpanBuilder = {
this.initialTags = this.initialTags + (key -> value.toString)
this
}
override def withTag(key: String, value: Number): io.opentracing.Tracer.SpanBuilder = {
this.initialTags = this.initialTags + (key -> value.toString)
this
}
override def withStartTimestamp(microseconds: Long): io.opentracing.Tracer.SpanBuilder = {
this.startTimestamp = microseconds
this
}
override def ignoreActiveSpan(): io.opentracing.Tracer.SpanBuilder = {
this.useActiveSpanAsParent = false
this
}
override def start(): io.opentracing.Span =
startManual()
override def startActive(): io.opentracing.ActiveSpan =
makeActive(startManual())
override def startManual(): Span = {
val startTimestampMicros = if(startTimestamp != 0L) startTimestamp else Clock.microTimestamp()
if(parentContext == null && useActiveSpanAsParent) {
val possibleParent = activeSpan()
if(possibleParent != null)
parentContext = possibleParent.context().asInstanceOf[SpanContext]
}
val spanContext =
if(parentContext != null)
new SpanContext(parentContext.traceID, createID(), parentContext.spanID, parentContext.sampled, initialTags)
else {
val traceID = createID()
new SpanContext(traceID, traceID, 0L, sampler.decide(traceID), initialTags)
}
//metricsRecorder.createdSpans.increment()
new Span(spanContext, operationName, initialTags, startTimestampMicros, ???, reporterRegistry)
}
private def createID(): Long =
ThreadLocalRandom.current().nextLong()
}
}