introduce the SpanCustomizer API

2 files changed, 64 insertions, 61 deletions

diff --git a/kamon-testkit/src/main/scala/kamon/testkit/SpanInspection.scala b/kamon-testkit/src/main/scala/kamon/testkit/SpanInspection.scala
new file mode 100644
index 00000000..c4a83a73
--- /dev/null
+++ b/kamon-testkit/src/main/scala/kamon/testkit/SpanInspection.scala
@@ -0,0 +1,64 @@
+package kamon.testkit
+
+import kamon.trace.{Span, SpanContext}
+import kamon.trace.Span.FinishedSpan
+import kamon.util.Clock
+
+import scala.reflect.ClassTag
+import scala.util.Try
+
+trait SpanInspection {
+
+  def inspect(span: Span): SpanInspection.Inspector =
+    new SpanInspection.Inspector(span)
+}
+
+object SpanInspection {
+
+  class Inspector(span: Span) {
+    private val (realSpan, spanData) = Try {
+      val realSpan = span match {
+        case _: Span.Local => span
+      }
+
+      val spanData = invoke[Span.Local, FinishedSpan](realSpan, "toFinishedSpan", classOf[Long] -> Long.box(Clock.microTimestamp()))
+      (realSpan, spanData)
+    }.getOrElse((null, null))
+
+    def isEmpty: Boolean =
+      realSpan == null
+
+    def spanTag(key: String): Option[Span.TagValue] =
+      spanData.tags.get(key)
+
+    def spanTags(): Map[String, Span.TagValue] =
+      spanData.tags
+
+    def metricTags(): Map[String, String] =
+      getField[Span.Local, Map[String, String]](realSpan, "customMetricTags")
+
+    def startTimestamp(): Long =
+      getField[Span.Local, Long](realSpan, "startTimestampMicros")
+
+    def context(): SpanContext =
+      spanData.context
+
+    def operationName(): String =
+      spanData.operationName
+
+
+    private def getField[T, R](target: Any, fieldName: String)(implicit classTag: ClassTag[T]): R = {
+      val toFinishedSpanMethod = classTag.runtimeClass.getDeclaredFields.find(_.getName.contains(fieldName)).get
+      toFinishedSpanMethod.setAccessible(true)
+      toFinishedSpanMethod.get(target).asInstanceOf[R]
+    }
+
+    private def invoke[T, R](target: Any, fieldName: String, parameters: (Class[_], AnyRef)*)(implicit classTag: ClassTag[T]): R = {
+      val parameterClasses = parameters.map(_._1)
+      val parameterInstances = parameters.map(_._2)
+      val toFinishedSpanMethod = classTag.runtimeClass.getDeclaredMethod(fieldName, parameterClasses: _*)
+      toFinishedSpanMethod.setAccessible(true)
+      toFinishedSpanMethod.invoke(target, parameterInstances: _*).asInstanceOf[R]
+    }
+  }
+}
\ No newline at end of file
diff --git a/kamon-testkit/src/main/scala/kamon/testkit/SpanInspector.scala b/kamon-testkit/src/main/scala/kamon/testkit/SpanInspector.scala
deleted file mode 100644
index 25f7ee06..00000000
--- a/kamon-testkit/src/main/scala/kamon/testkit/SpanInspector.scala
+++ /dev/null
@@ -1,61 +0,0 @@
-package kamon.testkit
-
-import kamon.trace.{Span, SpanContext}
-import kamon.trace.Span.FinishedSpan
-import kamon.util.Clock
-
-import scala.reflect.ClassTag
-import scala.util.Try
-
-class SpanInspector(span: Span) {
-  private val (realSpan, spanData) = Try {
-    val realSpan = span match {
-      case _: Span.Local => span
-    }
-
-    val spanData = invoke[Span.Local, FinishedSpan](realSpan, "toFinishedSpan", classOf[Long] -> Long.box(Clock.microTimestamp()))
-    (realSpan, spanData)
-  }.getOrElse((null, null))
-
-  def isEmpty: Boolean =
-    realSpan == null
-
-  def spanTag(key: String): Option[Span.TagValue] =
-    spanData.tags.get(key)
-
-  def spanTags(): Map[String, Span.TagValue] =
-    spanData.tags
-
-  def metricTags(): Map[String, String] =
-    getField[Span.Local, Map[String, String]](realSpan, "customMetricTags")
-
-  def startTimestamp(): Long =
-    getField[Span.Local, Long](realSpan, "startTimestampMicros")
-
-  def context(): SpanContext =
-    spanData.context
-
-  def operationName(): String =
-    spanData.operationName
-
-
-
-
-  private def getField[T, R](target: Any, fieldName: String)(implicit classTag: ClassTag[T]): R = {
-    val toFinishedSpanMethod = classTag.runtimeClass.getDeclaredFields.find(_.getName.contains(fieldName)).get
-    toFinishedSpanMethod.setAccessible(true)
-    toFinishedSpanMethod.get(target).asInstanceOf[R]
-  }
-
-  private def invoke[T, R](target: Any, fieldName: String, parameters: (Class[_], AnyRef)*)(implicit classTag: ClassTag[T]): R = {
-    val parameterClasses = parameters.map(_._1)
-    val parameterInstances = parameters.map(_._2)
-    val toFinishedSpanMethod = classTag.runtimeClass.getDeclaredMethod(fieldName, parameterClasses: _*)
-    toFinishedSpanMethod.setAccessible(true)
-    toFinishedSpanMethod.invoke(target, parameterInstances: _*).asInstanceOf[R]
-  }
-}
-
-object SpanInspector {
-  def apply(span: Span): SpanInspector = new SpanInspector(span)
-}