Add logging and noop tracers

2 files changed, 53 insertions, 0 deletions

diff --git a/src/main/scala/LoggingTracer.scala b/src/main/scala/LoggingTracer.scala
new file mode 100644
index 0000000..b22d22a
--- /dev/null
+++ b/src/main/scala/LoggingTracer.scala
@@ -0,0 +1,48 @@
+package xyz.driver.tracing
+
+import java.util.UUID
+import java.time.{Instant, ZoneId}
+import java.time.format.DateTimeFormatter
+import akka.event.LoggingAdapter
+import spray.json._
+
+class LoggingTracer(implicit logger: LoggingAdapter) extends Tracer {
+  import LoggingTracer.JsonProtocol._
+
+  override def submit(span: Span): Unit = logger.debug(
+    span.toJson.compactPrint
+  )
+}
+
+object LoggingTracer {
+
+  object JsonProtocol extends DefaultJsonProtocol {
+    implicit def uuidFormat: JsonFormat[UUID] = jsonFormat(
+      { (js: JsValue) =>
+        js match {
+          case JsString(str) => UUID.fromString(str)
+          case other         => deserializationError("expected string as UUID")
+        }
+      }, { (uuid: UUID) =>
+        JsString(uuid.toString)
+      }
+    )
+
+    private val timeFormatter = DateTimeFormatter
+      .ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSSX")
+      .withZone(ZoneId.of("UTC"))
+
+    implicit def instantFormat: JsonFormat[Instant] = jsonFormat(
+      { (js: JsValue) =>
+        js match {
+          case JsString(str) => Instant.parse(str)
+          case other         => deserializationError(s"`$other` is not a valid instant")
+        }
+      }, { (instant: Instant) =>
+        JsString(timeFormatter.format(instant))
+      }
+    )
+    implicit def spanFormat: RootJsonFormat[Span] = jsonFormat7(Span.apply)
+  }
+
+}
diff --git a/src/main/scala/NoTracer.scala b/src/main/scala/NoTracer.scala
new file mode 100644
index 0000000..904f28f
--- /dev/null
+++ b/src/main/scala/NoTracer.scala
@@ -0,0 +1,5 @@
+package xyz.driver.tracing
+
+object NoTracer extends Tracer {
+  override def submit(span: Span): Unit = ()
+}