Introduce explicit option for disabling ingestion sampling

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/configuration/Configuration.java

@@ -159,13 +159,19 @@ public static class Role {
 
   public static class Sampling {
 
-    // fixed percentage of requests
-    @Nullable public Double percentage;
-
     // default is 5 requests per second (set in ConfigurationBuilder if neither percentage nor
     // requestsPerSecond was configured)
     @Nullable public Double requestsPerSecond;
 
+    // fixed percentage of requests
+    @Nullable public Double percentage;
+
+    // in the future it would be nice for ingestion sampling to be an independent option
+    // from percentage (and to default to false), but currently ingestion sampling is enabled
+    // when percentage is set to 100, and this can be used to disable ingestion sampling even
+    // in that case (when percentage is 100)
+    @Nullable public Boolean ingestion;
+
     // this config option only existed in one BETA release (3.4.0-BETA)
     @Deprecated @Nullable public Double limitPerSecond;
 

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/configuration/ConfigurationBuilder.java

@@ -269,12 +269,18 @@ private static void logConfigurationWarnings(Configuration config) {
               + "If you're on premise, you can use APPLICATIONINSIGHTS_AUTHENTICATION_STRING environment variable to pass the client ID and secret, "
               + "e.g. APPLICATIONINSIGHTS_AUTHENTICATION_STRING=Authorization=AAD;ClientId={CLIENT_ID};ClientSecret={CLIENT_SECRET}.");
     }
-    if (config.sampling.percentage != null && config.sampling.requestsPerSecond != null) {
+    if (config.sampling.requestsPerSecond != null && config.sampling.percentage != null) {
       configurationLogger.warn(
           "Sampling \"requestsPerSecond\" and \"percentage\" should not be used at the same time."
               + " Please remove one of them.");
       config.sampling.percentage = null; // requestsPerSecond takes priority
     }
+    if (config.sampling.requestsPerSecond != null && config.sampling.ingestion != null) {
+      configurationLogger.warn(
+          "Sampling \"requestsPerSecond\" and \"ingestion\" should not be used at the same time."
+              + " Please remove one of them.");
+      config.sampling.ingestion = null; // requestsPerSecond takes priority
+    }
 
     logWarningIfUsingInternalAttributes(config);
   }

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/sampling/Samplers.java

@@ -21,12 +21,15 @@ public static Sampler getSampler(
       sampler = new AiSampler(requestSamplingPercentage, parentlessDependencySamplingPercentage);
     } else if (sampling.percentage != null) {
       SamplingPercentage samplingPercentage;
-      if (sampling.percentage == 100) {
+      if (sampling.percentage == 100 && !Boolean.FALSE.equals(sampling.ingestion)) {
         samplingPercentage = SamplingPercentage.useIngestionSampling();
       } else {
         samplingPercentage = SamplingPercentage.fixed(sampling.percentage);
       }
       sampler = new AiSampler(samplingPercentage, samplingPercentage);
+    } else if (Boolean.TRUE.equals(sampling.ingestion)) {
+      SamplingPercentage samplingPercentage = SamplingPercentage.useIngestionSampling();
+      sampler = new AiSampler(samplingPercentage, samplingPercentage);
     } else {
       throw new AssertionError("ConfigurationBuilder should have set the default sampling");
     }

smoke-tests/apps/Sampling/src/main/java/com/microsoft/applicationinsights/smoketestapp/NoSamplingServlet.java → smoke-tests/apps/Sampling/src/main/java/com/microsoft/applicationinsights/smoketestapp/SimpleServlet.java

@@ -13,10 +13,10 @@
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-@WebServlet("/no-sampling")
-public class NoSamplingServlet extends HttpServlet {
+@WebServlet("/simple")
+public class SimpleServlet extends HttpServlet {
 
-  private static final Logger logger = Logger.getLogger(NoSamplingServlet.class.getName());
+  private static final Logger logger = Logger.getLogger(SimpleServlet.class.getName());
 
   private final TelemetryClient client = new TelemetryClient();
 

smoke-tests/apps/Sampling/src/smokeTest/java/com/microsoft/applicationinsights/smoketest/IngestionSamplingTest.java

@@ -27,25 +27,25 @@ abstract class IngestionSamplingTest {
   @RegisterExtension static final SmokeTestExtension testing = SmokeTestExtension.create();
 
   @Test
-  @TargetUri(value = "/no-sampling", callCount = 1000)
-  void testNoSampling() throws Exception {
+  @TargetUri(value = "/simple", callCount = 100)
+  void testIngestionSampling() throws Exception {
     long start = System.nanoTime();
-    while (testing.mockedIngestion.getCountForType("RequestData") < 1000
+    while (testing.mockedIngestion.getCountForType("RequestData") < 100
         && NANOSECONDS.toSeconds(System.nanoTime() - start) < 10) {
       // just wait and do nothing
     }
     Thread.sleep(SECONDS.toMillis(10));
 
-    assertThat(testing.mockedIngestion.getCountForType("RequestData")).isEqualTo(1000);
+    assertThat(testing.mockedIngestion.getCountForType("RequestData")).isEqualTo(100);
 
     List<Envelope> requestEnvelopes =
         testing.mockedIngestion.getItemsEnvelopeDataType("RequestData");
-    assertThat(requestEnvelopes.size()).isEqualTo(1000);
+    assertThat(requestEnvelopes.size()).isEqualTo(100);
     List<Envelope> eventEnvelopes = testing.mockedIngestion.getItemsEnvelopeDataType("EventData");
-    assertThat(eventEnvelopes.size()).isEqualTo(1000);
+    assertThat(eventEnvelopes.size()).isEqualTo(100);
     List<Envelope> messageEnvelopes =
         testing.mockedIngestion.getItemsEnvelopeDataType("MessageData");
-    assertThat(messageEnvelopes.size()).isEqualTo(1000);
+    assertThat(messageEnvelopes.size()).isEqualTo(100);
 
     for (Envelope requestEnvelope : requestEnvelopes) {
       assertThat(requestEnvelope.getSampleRate()).isNull();

smoke-tests/apps/Sampling/src/smokeTest/java/com/microsoft/applicationinsights/smoketest/NoIngestionSamplingTest.java

@@ -0,0 +1,87 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+package com.microsoft.applicationinsights.smoketest;
+
+import static com.microsoft.applicationinsights.smoketest.EnvironmentValue.TOMCAT_8_JAVA_11;
+import static com.microsoft.applicationinsights.smoketest.EnvironmentValue.TOMCAT_8_JAVA_11_OPENJ9;
+import static com.microsoft.applicationinsights.smoketest.EnvironmentValue.TOMCAT_8_JAVA_17;
+import static com.microsoft.applicationinsights.smoketest.EnvironmentValue.TOMCAT_8_JAVA_21;
+import static com.microsoft.applicationinsights.smoketest.EnvironmentValue.TOMCAT_8_JAVA_21_OPENJ9;
+import static com.microsoft.applicationinsights.smoketest.EnvironmentValue.TOMCAT_8_JAVA_8;
+import static com.microsoft.applicationinsights.smoketest.EnvironmentValue.TOMCAT_8_JAVA_8_OPENJ9;
+import static com.microsoft.applicationinsights.smoketest.EnvironmentValue.WILDFLY_13_JAVA_8;
+import static com.microsoft.applicationinsights.smoketest.EnvironmentValue.WILDFLY_13_JAVA_8_OPENJ9;
+import static java.util.concurrent.TimeUnit.NANOSECONDS;
+import static java.util.concurrent.TimeUnit.SECONDS;
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.microsoft.applicationinsights.smoketest.schemav2.Envelope;
+import java.util.List;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+@UseAgent("applicationinsights-no-ingestion-sampling.json")
+abstract class NoIngestionSamplingTest {
+
+  @RegisterExtension static final SmokeTestExtension testing = SmokeTestExtension.create();
+
+  @Test
+  @TargetUri(value = "/simple", callCount = 100)
+  void testNoIngestionSampling() throws Exception {
+    long start = System.nanoTime();
+    while (testing.mockedIngestion.getCountForType("RequestData") < 100
+        && NANOSECONDS.toSeconds(System.nanoTime() - start) < 10) {
+      // just wait and do nothing
+    }
+    Thread.sleep(SECONDS.toMillis(10));
+
+    assertThat(testing.mockedIngestion.getCountForType("RequestData")).isEqualTo(100);
+
+    List<Envelope> requestEnvelopes =
+        testing.mockedIngestion.getItemsEnvelopeDataType("RequestData");
+    assertThat(requestEnvelopes.size()).isEqualTo(100);
+    List<Envelope> eventEnvelopes = testing.mockedIngestion.getItemsEnvelopeDataType("EventData");
+    assertThat(eventEnvelopes.size()).isEqualTo(100);
+    List<Envelope> messageEnvelopes =
+        testing.mockedIngestion.getItemsEnvelopeDataType("MessageData");
+    assertThat(messageEnvelopes.size()).isEqualTo(100);
+
+    for (Envelope requestEnvelope : requestEnvelopes) {
+      assertThat(requestEnvelope.getSampleRate()).isEqualTo(100);
+    }
+    for (Envelope eventEnvelope : eventEnvelopes) {
+      assertThat(eventEnvelope.getSampleRate()).isEqualTo(100);
+    }
+    for (Envelope messageEnvelope : messageEnvelopes) {
+      assertThat(messageEnvelope.getSampleRate()).isEqualTo(100);
+    }
+  }
+
+  @Environment(TOMCAT_8_JAVA_8)
+  static class Tomcat8Java8Test extends NoIngestionSamplingTest {}
+
+  @Environment(TOMCAT_8_JAVA_8_OPENJ9)
+  static class Tomcat8Java8OpenJ9Test extends NoIngestionSamplingTest {}
+
+  @Environment(TOMCAT_8_JAVA_11)
+  static class Tomcat8Java11Test extends NoIngestionSamplingTest {}
+
+  @Environment(TOMCAT_8_JAVA_11_OPENJ9)
+  static class Tomcat8Java11OpenJ9Test extends NoIngestionSamplingTest {}
+
+  @Environment(TOMCAT_8_JAVA_17)
+  static class Tomcat8Java17Test extends NoIngestionSamplingTest {}
+
+  @Environment(TOMCAT_8_JAVA_21)
+  static class Tomcat8Java21Test extends NoIngestionSamplingTest {}
+
+  @Environment(TOMCAT_8_JAVA_21_OPENJ9)
+  static class Tomcat8Java21OpenJ9Test extends NoIngestionSamplingTest {}
+
+  @Environment(WILDFLY_13_JAVA_8)
+  static class Wildfly13Java8Test extends NoIngestionSamplingTest {}
+
+  @Environment(WILDFLY_13_JAVA_8_OPENJ9)
+  static class Wildfly13Java8OpenJ9Test extends NoIngestionSamplingTest {}
+}

smoke-tests/apps/Sampling/src/smokeTest/java/com/microsoft/applicationinsights/smoketest/SamplingTest.java

@@ -27,7 +27,7 @@ abstract class SamplingTest {
   @RegisterExtension static final SmokeTestExtension testing = SmokeTestExtension.create();
 
   @Test
-  @TargetUri(value = "/sampling", callCount = 100)
+  @TargetUri(value = "/simple", callCount = 100)
   void testSampling() throws Exception {
     // super super low chance that number of sampled requests is less than 25
     long start = System.nanoTime();

smoke-tests/apps/Sampling/src/smokeTest/resources/applicationinsights-no-ingestion-sampling.json

@@ -0,0 +1,10 @@
+{
+  "role": {
+    "name": "testrolename",
+    "instance": "testroleinstance"
+  },
+  "sampling": {
+    "percentage": 100,
+    "ingestion": false
+  }
+}