add a double length trace identifier implementation of IdentityProvider

2 files changed, 128 insertions, 3 deletions

diff --git a/kamon-core/src/main/scala/kamon/trace/IdentityProvider.scala b/kamon-core/src/main/scala/kamon/trace/IdentityProvider.scala
index 25e8f3c0..0e7d3e7d 100644
--- a/kamon-core/src/main/scala/kamon/trace/IdentityProvider.scala
+++ b/kamon-core/src/main/scala/kamon/trace/IdentityProvider.scala
@@ -25,7 +25,7 @@ object IdentityProvider {
 
 
   class Default extends IdentityProvider {
-    private val generator = new Generator {
+    protected val longGenerator = new Generator {
       override def generate(): Identifier = {
         val data = ByteBuffer.wrap(new Array[Byte](8))
         val random = ThreadLocalRandom.current().nextLong()
@@ -50,11 +50,50 @@ object IdentityProvider {
       } getOrElse(IdentityProvider.NoIdentifier)
     }
 
-    override def traceIdentifierGenerator(): Generator = generator
-    override def spanIdentifierGenerator(): Generator = generator
+    override def traceIdentifierGenerator(): Generator = longGenerator
+    override def spanIdentifierGenerator(): Generator = longGenerator
   }
 
   object Default {
     def apply(): Default = new Default()
   }
+
+
+  class DoubleSizeTraceID extends Default {
+    private val doubleLongGenerator = new Generator {
+      override def generate(): Identifier = {
+        val data = ByteBuffer.wrap(new Array[Byte](16))
+        val highLong = ThreadLocalRandom.current().nextLong()
+        val lowLong = ThreadLocalRandom.current().nextLong()
+        data.putLong(highLong)
+        data.putLong(lowLong)
+
+        Identifier(HexCodec.toLowerHex(highLong) + HexCodec.toLowerHex(lowLong), data.array())
+      }
+
+      override def from(string: String): Identifier =  Try {
+        val highPart = HexCodec.lowerHexToUnsignedLong(string.substring(0, 16))
+        val lowPart = HexCodec.lowerHexToUnsignedLong(string.substring(16, 32))
+        val data = ByteBuffer.allocate(16)
+        data.putLong(highPart)
+        data.putLong(lowPart)
+
+        Identifier(string, data.array())
+      } getOrElse(IdentityProvider.NoIdentifier)
+
+      override def from(bytes: Array[Byte]): Identifier = Try {
+        val buffer = ByteBuffer.wrap(bytes)
+        val highLong = buffer.getLong
+        val lowLong = buffer.getLong
+
+        Identifier(HexCodec.toLowerHex(highLong) + HexCodec.toLowerHex(lowLong), bytes)
+      } getOrElse(IdentityProvider.NoIdentifier)
+    }
+
+    override def traceIdentifierGenerator(): Generator = doubleLongGenerator
+  }
+
+  object DoubleSizeTraceID {
+    def apply(): DoubleSizeTraceID = new DoubleSizeTraceID()
+  }
 }
\ No newline at end of file
diff --git a/kamon-core/src/test/scala/kamon/trace/DoubleLengthTraceIdentityGeneratorSpec.scala b/kamon-core/src/test/scala/kamon/trace/DoubleLengthTraceIdentityGeneratorSpec.scala
new file mode 100644
index 00000000..54e590ad
--- /dev/null
+++ b/kamon-core/src/test/scala/kamon/trace/DoubleLengthTraceIdentityGeneratorSpec.scala
@@ -0,0 +1,86 @@
+package kamon.trace
+
+import kamon.trace.IdentityProvider.Identifier
+import org.scalactic.TimesOnInt._
+import org.scalatest.{Matchers, OptionValues, WordSpecLike}
+
+class DoubleLengthTraceIdentityGeneratorSpec extends WordSpecLike with Matchers with OptionValues {
+  val idProvider = IdentityProvider.DoubleSizeTraceID()
+  val traceGenerator = idProvider.traceIdentifierGenerator()
+  val spanGenerator = idProvider.spanIdentifierGenerator()
+
+  "The DoubleSizeTraceID identity provider" when {
+    "generating trace identifiers" should {
+      "generate random longs (16 byte) identifiers" in {
+        100 times {
+          val Identifier(string, bytes) = traceGenerator.generate()
+
+          string.length should be(32)
+          bytes.length should be(16)
+        }
+      }
+
+      "decode the string representation back into a identifier" in {
+        100 times {
+          val identifier = traceGenerator.generate()
+          val decodedIdentifier = traceGenerator.from(identifier.string)
+
+          identifier.string should equal(decodedIdentifier.string)
+          identifier.bytes should equal(decodedIdentifier.bytes)
+        }
+      }
+
+      "decode the bytes representation back into a identifier" in {
+        100 times {
+          val identifier = traceGenerator.generate()
+          val decodedIdentifier = traceGenerator.from(identifier.bytes)
+
+          identifier.string should equal(decodedIdentifier.string)
+          identifier.bytes should equal(decodedIdentifier.bytes)
+        }
+      }
+
+      "return IdentityProvider.NoIdentifier if the provided input cannot be decoded into a Identifier" in {
+        traceGenerator.from("zzzz") shouldBe (IdentityProvider.NoIdentifier)
+        traceGenerator.from(Array[Byte](1)) shouldBe (IdentityProvider.NoIdentifier)
+      }
+    }
+
+    "generating span identifiers" should {
+      "generate random longs (8 byte) identifiers" in {
+        100 times {
+          val Identifier(string, bytes) = spanGenerator.generate()
+
+          string.length should be(16)
+          bytes.length should be(8)
+        }
+      }
+
+      "decode the string representation back into a identifier" in {
+        100 times {
+          val identifier = spanGenerator.generate()
+          val decodedIdentifier = spanGenerator.from(identifier.string)
+
+          identifier.string should equal(decodedIdentifier.string)
+          identifier.bytes should equal(decodedIdentifier.bytes)
+        }
+      }
+
+      "decode the bytes representation back into a identifier" in {
+        100 times {
+          val identifier = spanGenerator.generate()
+          val decodedIdentifier = spanGenerator.from(identifier.bytes)
+
+          identifier.string should equal(decodedIdentifier.string)
+          identifier.bytes should equal(decodedIdentifier.bytes)
+        }
+      }
+
+      "return IdentityProvider.NoIdentifier if the provided input cannot be decoded into a Identifier" in {
+        spanGenerator.from("zzzz") shouldBe (IdentityProvider.NoIdentifier)
+        spanGenerator.from(Array[Byte](1)) shouldBe (IdentityProvider.NoIdentifier)
+      }
+    }
+  }
+
+}