Use dynamic headers for otel-dc-llm

host/build.gradle

@@ -21,7 +21,7 @@ dependencies {
     implementation("io.opentelemetry.semconv:opentelemetry-semconv:1.23.1-alpha")
     implementation("com.fasterxml.jackson.dataformat:jackson-dataformat-yaml:2.16.0-rc1")
     implementation("org.snmp4j:snmp4j-agent:3.8.1")
-    implementation(files("libs/otel-dc-0.9.9.jar"))
+    implementation(files("libs/otel-dc-0.10.0.jar"))
     implementation(files("libs/simp-snmp-0.1.3.jar"))
 
     testImplementation("org.junit.jupiter:junit-jupiter-api:5.8.1")

internal/otel-dc/build.gradle

@@ -4,7 +4,7 @@ plugins {
 }
 
 group = "com.instana.dc"
-version = "0.9.9"
+version = "0.10.0"
 
 repositories {
     mavenCentral()

internal/otel-dc/src/main/java/com/instana/dc/AbstractDc.java

@@ -1,5 +1,12 @@
 package com.instana.dc;
 
+import java.time.Duration;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.TimeUnit;
+
+import static com.instana.dc.DcUtil.getCert;
+
 import io.opentelemetry.api.OpenTelemetry;
 import io.opentelemetry.api.metrics.Meter;
 import io.opentelemetry.exporter.otlp.http.metrics.OtlpHttpMetricExporter;
@@ -10,13 +17,6 @@
 import io.opentelemetry.sdk.metrics.export.PeriodicMetricReader;
 import io.opentelemetry.sdk.resources.Resource;
 
-import java.time.Duration;
-import java.util.Map;
-import java.util.concurrent.ConcurrentHashMap;
-import java.util.concurrent.TimeUnit;
-
-import static com.instana.dc.DcUtil.getCert;
-
 public abstract class AbstractDc implements IDc {
     private final Map<String, Meter> meters = new ConcurrentHashMap<>();
     private final Map<String, RawMetric> rawMetricsMap;
@@ -63,8 +63,10 @@ public static OtlpGrpcMetricExporter createOtlpGrpcMetricExporter(String otelBac
                 .setEndpoint(otelBackendUrl)
                 .setTimeout(timeout, TimeUnit.SECONDS);
 
+        HeadersSupplier supplier = HeadersSupplier.INSTANCE;
+        builder.setHeaders(supplier::getHeaders);
         if (headers != null) {
-            builder.setHeaders(() -> headers);
+            supplier.updateHeaders(headers);
         }
         if (cert != null) {
             builder.setTrustedCertificates(cert);
@@ -78,8 +80,10 @@ public static OtlpHttpMetricExporter createOtlpHttpMetricExporter(String otelBac
                 .setEndpoint(otelBackendUrl)
                 .setTimeout(timeout, TimeUnit.SECONDS);
 
+        HeadersSupplier supplier = HeadersSupplier.INSTANCE;
+        builder.setHeaders(supplier::getHeaders);
         if (headers != null) {
-            builder.setHeaders(() -> headers);
+            supplier.updateHeaders(headers);
         }
         if (cert != null) {
             builder.setTrustedCertificates(cert);

internal/otel-dc/src/main/java/com/instana/dc/HeadersSupplier.java

@@ -0,0 +1,23 @@
+/*
+ * (c) Copyright IBM Corp. 2024
+ * (c) Copyright Instana Inc.
+ */
+package com.instana.dc;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public enum HeadersSupplier {
+    INSTANCE;
+
+    private final Map<String, String> headers = new HashMap<>();
+
+    public synchronized void updateHeaders(Map<String, String> newHeaders) {
+        headers.clear();
+        headers.putAll(newHeaders);
+    }
+
+    public Map<String, String> getHeaders() {
+        return new HashMap<>(headers);
+    }
+}

llm/build.gradle

@@ -27,7 +27,7 @@ dependencies {
     implementation("com.google.protobuf:protobuf-java-util:3.23.4")
     implementation("com.linecorp.armeria:armeria:1.27.3")
     implementation("com.linecorp.armeria:armeria-grpc:1.27.3")
-    implementation(files("libs/otel-dc-0.9.9.jar"))
+    implementation(files("libs/otel-dc-0.10.0.jar"))
 
     testImplementation("org.junit.jupiter:junit-jupiter-api:5.8.1")
     testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.8.1")

llm/src/main/java/com/instana/dc/llm/impl/llm/MetricsCollectorService.java

@@ -1,11 +1,18 @@
 package com.instana.dc.llm.impl.llm;
 
+import static com.instana.dc.DcUtil.OTEL_EXPORTER_OTLP_HEADERS;
+
 import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.Objects;
 import java.util.logging.Logger;
 
 import com.google.common.collect.ImmutableList;
+import com.instana.dc.HeadersSupplier;
+import com.linecorp.armeria.common.HttpRequest;
+import com.linecorp.armeria.common.RequestContext;
+import com.linecorp.armeria.common.RequestHeaders;
 
 import io.grpc.stub.StreamObserver;
 import io.opentelemetry.proto.collector.metrics.v1.ExportMetricsServiceRequest;
@@ -190,6 +197,26 @@ public void export(
             ExportMetricsServiceRequest request,
             StreamObserver<ExportMetricsServiceResponse> responseObserver) {
 
+        if (System.getenv(OTEL_EXPORTER_OTLP_HEADERS) == null) {
+            HttpRequest httpRequest = RequestContext.current().request();
+            RequestHeaders headers = httpRequest!=null ? httpRequest.headers() : null;
+            if ( headers != null ) {
+                HeadersSupplier supplier = HeadersSupplier.INSTANCE;
+                Map<String, String> newHeaders = new HashMap<>();
+                String xInstanaKey = headers.get("x-instana-key");
+                if (xInstanaKey != null && !xInstanaKey.isEmpty()) {
+                    newHeaders.put("x-instana-key", xInstanaKey);
+                }
+                String xInstanaHost = headers.get("x-instana-host");
+                if (xInstanaHost != null && !xInstanaHost.isEmpty()) {
+                    newHeaders.put("x-instana-host", xInstanaHost);
+                }
+                if ( ! newHeaders.isEmpty() ) {
+                    supplier.updateHeaders(newHeaders);
+                }
+            }
+        }
+
         synchronized (mutex) {
             List<ResourceMetrics> allResourceMetrics = request.getResourceMetricsList();
             for (ResourceMetrics resourceMetrics : allResourceMetrics) {

rdb/build.gradle

@@ -20,7 +20,7 @@ dependencies {
     implementation("io.opentelemetry:opentelemetry-exporter-sender-okhttp:1.34.1")
     implementation("io.opentelemetry.semconv:opentelemetry-semconv:1.23.1-alpha")
     implementation("com.fasterxml.jackson.dataformat:jackson-dataformat-yaml:2.16.0-rc1")
-    implementation(files("libs/otel-dc-0.9.9.jar"))
+    implementation(files("libs/otel-dc-0.10.0.jar"))
     implementation(files("libs/ngdbc-2.4.64.jar"))
     implementation("org.apache.commons:commons-dbcp2:2.11.0")