Merge pull request #124 from DataDog/tyler/prevent-0-duration

Prevent traces from finishing with 0 duration

Author: tylerbenson

dd-trace/src/main/java/com/datadoghq/trace/DDBaseSpan.java

@@ -50,7 +50,9 @@ public final void finish() {
   }
 
   public final void finish(final long stoptimeMicros) {
-    this.durationNano = TimeUnit.MICROSECONDS.toNanos(stoptimeMicros - this.startTimeMicro);
+    // Ensure that duration is at least 1.  Less than 1 is possible due to our use of system clock instead of nano time.
+    this.durationNano =
+        Math.max(1, TimeUnit.MICROSECONDS.toNanos(stoptimeMicros - this.startTimeMicro));
     afterFinish();
   }
 

dd-trace/src/main/java/com/datadoghq/trace/DDTracer.java

@@ -223,15 +223,16 @@ private DDSpan startSpan() {
 
     @Override
     public ActiveSpan startActive() {
-      final ActiveSpan activeSpan = spanSource.makeActive(startSpan());
-      log.debug("{} - Starting a new active span.", activeSpan);
+      final DDSpan span = startSpan();
+      final ActiveSpan activeSpan = spanSource.makeActive(span);
+      log.debug("Starting a new active span: {}", span);
       return activeSpan;
     }
 
     @Override
     public DDSpan startManual() {
       final DDSpan span = startSpan();
-      log.debug("{} - Starting a new manuel span.", span);
+      log.debug("Starting a new manual span: {}", span);
       return span;
     }
 

dd-trace/src/main/java/com/datadoghq/trace/writer/DDAgentWriter.java

@@ -141,11 +141,13 @@ public void run() {
       final Future<Long> future = executor.submit(new SendingTask());
       try {
         final long nbTraces = future.get(API_TIMEOUT_SECONDS, TimeUnit.SECONDS);
-        log.debug("Successfully sending {} traces to the API", nbTraces);
+        if (nbTraces > 0) {
+          log.debug("Successfully sent {} traces to the API", nbTraces);
+        }
       } catch (final TimeoutException e) {
-        log.debug("Timeout! Fail to send traces to the API: {}", e.getMessage());
+        log.debug("Timeout! Failed to send traces to the API: {}", e.getMessage());
       } catch (final Throwable e) {
-        log.debug("Fail to send traces to the API: {}", e.getMessage());
+        log.debug("Failed to send traces to the API: {}", e.getMessage());
       }
     }