Add azure_monitor to metrics exporter for AKS

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/init/AiConfigCustomizer.java

@@ -5,6 +5,8 @@
 
 import static java.util.concurrent.TimeUnit.SECONDS;
 
+import com.azure.monitor.opentelemetry.autoconfigure.implementation.AzureMonitorExporterProviderKeys;
+import com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.Strings;
 import com.microsoft.applicationinsights.agent.internal.configuration.Configuration;
 import com.microsoft.applicationinsights.agent.internal.legacyheaders.DelegatingPropagatorProvider;
 import io.opentelemetry.sdk.autoconfigure.spi.ConfigProperties;
@@ -115,7 +117,14 @@ public Map<String, String> apply(ConfigProperties otelConfig) {
     }
 
     String metricsExporter = otelConfig.getString("otel.metrics.exporter");
-    if (metricsExporter == null) {
+    String aksNamespaceId = System.getenv("AKS_ARM_NAMESPACE_ID");
+    String metricsToLogAnalyticsEnabled =
+        otelConfig.getString("applicationinsights.metrics.to.loganalytics.enabled");
+    if (isAksAttach(aksNamespaceId)) {
+      properties.put(
+          "otel.metrics.exporter",
+          updateMetricsExporter(metricsExporter, metricsToLogAnalyticsEnabled));
+    } else if (metricsExporter == null) {
       // this overrides the default "otlp" so the exporter can be configured later
       properties.put("otel.metrics.exporter", "none");
     }
@@ -343,4 +352,55 @@ private static <T> String join(List<T> values, char separator) {
     }
     return sb.toString();
   }
+
+  // visible for tests
+  static boolean isAksAttach(String aksNamespaceId) {
+    return !Strings.isNullOrEmpty(aksNamespaceId);
+  }
+
+  static String updateMetricsExporter(String metricsExporter, String metricsToLogAnalyticsEnabled) {
+    String azureMonitorName = AzureMonitorExporterProviderKeys.EXPORTER_NAME;
+    // If AMLE is true, configure both otlp and azure monitor exporters
+    if (Boolean.parseBoolean(metricsToLogAnalyticsEnabled)) {
+      // 1. Set default to "azure_monitor,otlp"
+      // 2. If exporter is "none", change to "azure_monitor,otlp" (AMLE true has higher priority
+      // than none)
+      if (metricsExporter == null
+          || metricsExporter.isEmpty()
+          || metricsExporter.equalsIgnoreCase("none")) {
+        return azureMonitorName + ",otlp";
+      }
+      // 3. If either azure monitor or otlp is missing, add them
+      if (!metricsExporter.contains(azureMonitorName)) {
+        metricsExporter += "," + azureMonitorName;
+      }
+      if (!metricsExporter.contains("otlp")) {
+        metricsExporter += ",otlp";
+      }
+      return metricsExporter;
+    }
+
+    // If AMLE is unset:
+    if (metricsToLogAnalyticsEnabled == null || metricsToLogAnalyticsEnabled.isEmpty()) {
+      if (metricsExporter == null || metricsExporter.isEmpty()) {
+        // Set default to "azure_monitor,otlp"
+        return azureMonitorName + ",otlp";
+      } else if (metricsExporter.contains(azureMonitorName) && !metricsExporter.contains("otlp")) {
+        // if azure monitor is already present and otlp is not, add otlp
+        metricsExporter += ",otlp";
+      }
+      return metricsExporter;
+    }
+
+    // If AMLE is false, configure only azure monitor exporter.
+    // 1. Default is azure monitor
+    // 2. If otlp is set, cancel it and replace with azure monitor (AMLE false has higher priority
+    // than otlp setting)
+    if (metricsExporter == null
+        || metricsExporter.isEmpty()
+        || metricsExporter.contains(azureMonitorName)) {
+      return azureMonitorName;
+    }
+    return metricsExporter;
+  }
 }

agent/agent-tooling/src/test/java/com/microsoft/applicationinsights/agent/internal/init/AiConfigCustomizerTest.java

@@ -0,0 +1,92 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+package com.microsoft.applicationinsights.agent.internal.init;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.stream.Stream;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+class AiConfigCustomizerTest {
+
+  @Test
+  void isAksAttach() {
+    assertThat(AiConfigCustomizer.isAksAttach("dummy-aks-namespace")).isTrue();
+
+    assertThat(AiConfigCustomizer.isAksAttach(null)).isFalse();
+    assertThat(AiConfigCustomizer.isAksAttach("")).isFalse();
+  }
+
+  @Test
+  void updateMetricsExporter_ExporterUnset() {
+
+    assertThat(AiConfigCustomizer.updateMetricsExporter(null, null))
+        .isEqualTo("azure_monitor,otlp");
+
+    assertThat(AiConfigCustomizer.updateMetricsExporter("", null)).isEqualTo("azure_monitor,otlp");
+
+    assertThat(AiConfigCustomizer.updateMetricsExporter(null, "true"))
+        .isEqualTo("azure_monitor,otlp");
+
+    assertThat(AiConfigCustomizer.updateMetricsExporter(null, "True"))
+        .isEqualTo("azure_monitor,otlp");
+  }
+
+  static Stream<Arguments> stringPairs() {
+    return Stream.of(
+        Arguments.of("none", "none"),
+        Arguments.of("azure_monitor", "azure_monitor,otlp"),
+        Arguments.of("azure_monitor,otlp", "azure_monitor,otlp"),
+        Arguments.of("otlp", "otlp"));
+  }
+
+  @ParameterizedTest
+  @MethodSource("stringPairs")
+  void updateMetricsExporter_ExporterSet_AMLE_Unset(
+      String metricsExporter, String expectAzureMonitor) {
+    assertThat(AiConfigCustomizer.updateMetricsExporter(metricsExporter, null))
+        .isEqualTo(expectAzureMonitor);
+    assertThat(AiConfigCustomizer.updateMetricsExporter(metricsExporter, ""))
+        .isEqualTo(expectAzureMonitor);
+  }
+
+  static Stream<Arguments> stringPairs2() {
+    return Stream.of(
+        Arguments.of("none", "azure_monitor,otlp"),
+        Arguments.of("azure_monitor", "azure_monitor,otlp"),
+        Arguments.of("azure_monitor,otlp", "azure_monitor,otlp"),
+        Arguments.of("otlp", "otlp,azure_monitor"));
+  }
+
+  @ParameterizedTest
+  @MethodSource("stringPairs2")
+  void updateMetricsExporter_ExporterSet_AMLE_True(
+      String metricsExporter, String expectAzureMonitor) {
+    assertThat(AiConfigCustomizer.updateMetricsExporter(metricsExporter, "true"))
+        .isEqualTo(expectAzureMonitor);
+    assertThat(AiConfigCustomizer.updateMetricsExporter(metricsExporter, "True"))
+        .isEqualTo(expectAzureMonitor);
+  }
+
+  static Stream<Arguments> stringPairs3() {
+    return Stream.of(
+        Arguments.of("none", "none"),
+        Arguments.of("azure_monitor", "azure_monitor"),
+        Arguments.of("azure_monitor,otlp", "azure_monitor"),
+        Arguments.of("otlp", "otlp"));
+  }
+
+  @ParameterizedTest
+  @MethodSource("stringPairs3")
+  void updateMetricsExporter_ExporterSet_AMLE_False(
+      String metricsExporter, String expectAzureMonitor) {
+    assertThat(AiConfigCustomizer.updateMetricsExporter(metricsExporter, "false"))
+        .isEqualTo(expectAzureMonitor);
+    assertThat(AiConfigCustomizer.updateMetricsExporter(metricsExporter, "False"))
+        .isEqualTo(expectAzureMonitor);
+  }
+}