Fixing FixedRateSampling to work in old and new version of sampling (#540)

Overriding default sampling percentage when programatically specified sampling percentage by user.

Author: anandsugumaran

core/src/main/java/com/microsoft/applicationinsights/internal/channel/sampling/FixedRateTelemetrySampler.java

@@ -113,7 +113,7 @@ else if (!includeTypes.isEmpty() && !includeTypes.contains(telemetry.getClass())
 
                         return false;
                     }
-                    samplingSupportingTelemetry.setSamplingPercentage(telemetrySamplingScore);
+                    samplingSupportingTelemetry.setSamplingPercentage(testedPercentage);
                 }
             }
         }

core/src/main/java/com/microsoft/applicationinsights/internal/channel/samplingV2/FixedRateSamplingTelemetryProcessor.java

@@ -159,16 +159,21 @@ public boolean process(Telemetry telemetry) {
                 if (samplingSupportingTelemetry.getSamplingPercentage() == null) {
 
                     samplingSupportingTelemetry.setSamplingPercentage(samplingPercentage);
-
-                    if (SamplingScoreGeneratorV2.getSamplingScore(telemetry) >= samplingPercentage) {
-
-                        InternalLogger.INSTANCE.info("Item %s sampled out", telemetry.getClass());
-                        return false;
-                    }
+                                        
+                    
                 } else {
                     InternalLogger.INSTANCE.info("Item has sampling percentage already set to :"
                             + samplingSupportingTelemetry.getSamplingPercentage());
+                    
+                    samplingPercentage = samplingSupportingTelemetry.getSamplingPercentage();
+                }
+                
+                if (SamplingScoreGeneratorV2.getSamplingScore(telemetry) >= samplingPercentage) {
+
+                    InternalLogger.INSTANCE.info("Item %s sampled out", telemetry.getClass());
+                    return false;
                 }
+                
             } else {
                 InternalLogger.INSTANCE.trace("Skip sampling since %s type is not sampling applicable", telemetry.getClass());
             }

core/src/test/java/com/microsoft/applicationinsights/internal/channel/samplingV2/FixedRateSamplingTelemetryProcessorTest.java

@@ -56,16 +56,16 @@ public void telemetryItemHasSamplingPercentageSet() {
     }
 
     @Test
-    public void telemetryItemSamplingIsSkippedWhenSetByUser() {
+    public void telemetryItemSamplingWorksWhenSetByUser() {
         FixedRateSamplingTelemetryProcessor processor = new FixedRateSamplingTelemetryProcessor();
-        processor.setSamplingPercentage("0.0");
+        processor.setSamplingPercentage("100.0");
         Telemetry requestTelemetry = new RequestTelemetry();
-        ((SupportSampling)requestTelemetry).setSamplingPercentage(100.0);
+        ((SupportSampling)requestTelemetry).setSamplingPercentage(0.0);
         int sentCount = 0;
         if (processor.process(requestTelemetry)) {
             ++sentCount;
         }
-        Assert.assertEquals(1, sentCount);
+        Assert.assertEquals(0, sentCount);
     }
 
     @Test