Add common OTLP configuration for endpoint and headers

module/spring-boot-actuator-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -151,6 +151,16 @@
       "description": "Whether auto-configuration of logging is enabled to export logs.",
       "defaultValue": true
     },
+    {
+      "name": "management.opentelemetry.otlp.endpoint",
+      "type": "java.lang.String",
+      "description": "OTLP target endpoint URL."
+    },
+    {
+      "name": "management.opentelemetry.otlp.headers",
+      "type": "java.util.Map<java.lang.String,java.lang.String>",
+      "description": "Custom headers to be appended to OTLP requests."
+    },
     {
       "name": "management.server.add-application-context-header",
       "type": "java.lang.Boolean",

module/spring-boot-micrometer-metrics/src/main/java/org/springframework/boot/micrometer/metrics/autoconfigure/export/otlp/OtlpMetricsExportAutoConfiguration.java

@@ -39,6 +39,7 @@
 import org.springframework.boot.micrometer.metrics.autoconfigure.export.ConditionalOnEnabledMetricsExport;
 import org.springframework.boot.micrometer.metrics.autoconfigure.export.simple.SimpleMetricsExportAutoConfiguration;
 import org.springframework.boot.opentelemetry.autoconfigure.OpenTelemetryProperties;
+import org.springframework.boot.opentelemetry.autoconfigure.OtlpProperties;
 import org.springframework.boot.ssl.SslBundle;
 import org.springframework.boot.ssl.SslBundles;
 import org.springframework.boot.thread.Threading;
@@ -61,7 +62,7 @@
 @ConditionalOnBean(Clock.class)
 @ConditionalOnClass({ OtlpMeterRegistry.class, OpenTelemetryProperties.class })
 @ConditionalOnEnabledMetricsExport("otlp")
-@EnableConfigurationProperties({ OtlpMetricsProperties.class, OpenTelemetryProperties.class })
+@EnableConfigurationProperties({ OtlpMetricsProperties.class, OpenTelemetryProperties.class, OtlpProperties.class })
 public final class OtlpMetricsExportAutoConfiguration {
 
 	private final OtlpMetricsProperties properties;
@@ -72,16 +73,17 @@ public final class OtlpMetricsExportAutoConfiguration {
 
 	@Bean
 	@ConditionalOnMissingBean
-	OtlpMetricsConnectionDetails otlpMetricsConnectionDetails(ObjectProvider<SslBundles> sslBundles) {
-		return new PropertiesOtlpMetricsConnectionDetails(this.properties, sslBundles.getIfAvailable());
+	OtlpMetricsConnectionDetails otlpMetricsConnectionDetails(OtlpProperties otlpProperties,
+			ObjectProvider<SslBundles> sslBundles) {
+		return new PropertiesOtlpMetricsConnectionDetails(this.properties, otlpProperties, sslBundles.getIfAvailable());
 	}
 
 	@Bean
 	@ConditionalOnMissingBean
-	OtlpConfig otlpConfig(OpenTelemetryProperties openTelemetryProperties,
+	OtlpConfig otlpConfig(OtlpProperties otlpProperties, OpenTelemetryProperties openTelemetryProperties,
 			OtlpMetricsConnectionDetails connectionDetails, Environment environment) {
-		return new OtlpMetricsPropertiesConfigAdapter(this.properties, openTelemetryProperties, connectionDetails,
-				environment);
+		return new OtlpMetricsPropertiesConfigAdapter(this.properties, otlpProperties, openTelemetryProperties,
+				connectionDetails, environment);
 	}
 
 	@Bean
@@ -129,16 +131,27 @@ static class PropertiesOtlpMetricsConnectionDetails implements OtlpMetricsConnec
 
 		private final OtlpMetricsProperties properties;
 
+		private final OtlpProperties otlpProperties;
+
 		private final @Nullable SslBundles sslBundles;
 
-		PropertiesOtlpMetricsConnectionDetails(OtlpMetricsProperties properties, @Nullable SslBundles sslBundles) {
+		PropertiesOtlpMetricsConnectionDetails(OtlpMetricsProperties properties, OtlpProperties otlpProperties,
+				@Nullable SslBundles sslBundles) {
 			this.properties = properties;
+			this.otlpProperties = otlpProperties;
 			this.sslBundles = sslBundles;
 		}
 
 		@Override
 		public @Nullable String getUrl() {
-			return this.properties.getUrl();
+			if (StringUtils.hasLength(this.properties.getUrl())) {
+				return this.properties.getUrl();
+			}
+			String endpoint = this.otlpProperties.getEndpoint();
+			if (StringUtils.hasLength(endpoint)) {
+				return endpoint.endsWith("/") ? endpoint + "v1/metrics" : endpoint + "/v1/metrics";
+			}
+			return null;
 		}
 
 		@Override

module/spring-boot-micrometer-metrics/src/main/java/org/springframework/boot/micrometer/metrics/autoconfigure/export/otlp/OtlpMetricsPropertiesConfigAdapter.java

@@ -30,6 +30,7 @@
 import org.springframework.boot.micrometer.metrics.autoconfigure.export.properties.StepRegistryPropertiesConfigAdapter;
 import org.springframework.boot.opentelemetry.autoconfigure.OpenTelemetryProperties;
 import org.springframework.boot.opentelemetry.autoconfigure.OpenTelemetryResourceAttributes;
+import org.springframework.boot.opentelemetry.autoconfigure.OtlpProperties;
 import org.springframework.core.env.Environment;
 import org.springframework.util.CollectionUtils;
 
@@ -43,16 +44,19 @@
 class OtlpMetricsPropertiesConfigAdapter extends StepRegistryPropertiesConfigAdapter<OtlpMetricsProperties>
 		implements OtlpConfig {
 
+	private final OtlpProperties otlpProperties;
+
 	private final OpenTelemetryProperties openTelemetryProperties;
 
 	private final OtlpMetricsConnectionDetails connectionDetails;
 
 	private final Environment environment;
 
-	OtlpMetricsPropertiesConfigAdapter(OtlpMetricsProperties properties,
+	OtlpMetricsPropertiesConfigAdapter(OtlpMetricsProperties properties, OtlpProperties otlpProperties,
 			OpenTelemetryProperties openTelemetryProperties, OtlpMetricsConnectionDetails connectionDetails,
 			Environment environment) {
 		super(properties);
+		this.otlpProperties = otlpProperties;
 		this.connectionDetails = connectionDetails;
 		this.openTelemetryProperties = openTelemetryProperties;
 		this.environment = environment;
@@ -88,7 +92,9 @@ public Map<String, String> resourceAttributes() {
 
 	@Override
 	public Map<String, String> headers() {
-		return obtain(OtlpMetricsProperties::getHeaders, OtlpConfig.super::headers);
+		Map<String, String> headers = new LinkedHashMap<>(this.otlpProperties.getHeaders());
+		headers.putAll(obtain(OtlpMetricsProperties::getHeaders, OtlpConfig.super::headers));
+		return Collections.unmodifiableMap(headers);
 	}
 
 	@Override

module/spring-boot-micrometer-metrics/src/test/java/org/springframework/boot/micrometer/metrics/autoconfigure/export/otlp/OtlpMetricsExportAutoConfigurationTests.java

@@ -266,6 +266,17 @@ public SslBundle getSslBundle() {
 			});
 	}
 
+	@Test
+	void testUrlFallbackToCommonOtlpEndpoint() {
+		this.contextRunner.withUserConfiguration(BaseConfiguration.class)
+			.withPropertyValues("management.opentelemetry.otlp.endpoint=http://common-host:4318")
+			.run((context) -> {
+				assertThat(context).hasSingleBean(OtlpConfig.class);
+				OtlpConfig config = context.getBean(OtlpConfig.class);
+				assertThat(config.url()).isEqualTo("http://common-host:4318/v1/metrics");
+			});
+	}
+
 	private HttpClient extractHttpClient(OtlpHttpMetricsSender metricsSender) {
 		Object field = ReflectionTestUtils.getField(metricsSender, "httpSender");
 		assertThat(field).isNotNull();

module/spring-boot-micrometer-metrics/src/test/java/org/springframework/boot/micrometer/metrics/autoconfigure/export/otlp/OtlpMetricsPropertiesConfigAdapterTests.java

@@ -28,6 +28,7 @@
 import org.springframework.boot.micrometer.metrics.autoconfigure.export.otlp.OtlpMetricsExportAutoConfiguration.PropertiesOtlpMetricsConnectionDetails;
 import org.springframework.boot.micrometer.metrics.autoconfigure.export.otlp.OtlpMetricsProperties.Meter;
 import org.springframework.boot.opentelemetry.autoconfigure.OpenTelemetryProperties;
+import org.springframework.boot.opentelemetry.autoconfigure.OtlpProperties;
 import org.springframework.mock.env.MockEnvironment;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -44,6 +45,8 @@ class OtlpMetricsPropertiesConfigAdapterTests {
 
 	private OtlpMetricsProperties properties;
 
+	private OtlpProperties otlpProperties;
+
 	private OpenTelemetryProperties openTelemetryProperties;
 
 	private MockEnvironment environment;
@@ -53,9 +56,10 @@ class OtlpMetricsPropertiesConfigAdapterTests {
 	@BeforeEach
 	void setUp() {
 		this.properties = new OtlpMetricsProperties();
+		this.otlpProperties = new OtlpProperties();
 		this.openTelemetryProperties = new OpenTelemetryProperties();
 		this.environment = new MockEnvironment();
-		this.connectionDetails = new PropertiesOtlpMetricsConnectionDetails(this.properties, null);
+		this.connectionDetails = new PropertiesOtlpMetricsConnectionDetails(this.properties, this.otlpProperties, null);
 	}
 
 	@Test
@@ -238,8 +242,41 @@ void shouldUseDefaultApplicationGroupIfApplicationGroupIsNotSet() {
 	}
 
 	private OtlpMetricsPropertiesConfigAdapter createAdapter() {
-		return new OtlpMetricsPropertiesConfigAdapter(this.properties, this.openTelemetryProperties,
-				this.connectionDetails, this.environment);
+		return new OtlpMetricsPropertiesConfigAdapter(this.properties, this.otlpProperties,
+				this.openTelemetryProperties, this.connectionDetails, this.environment);
+	}
+
+	@Test
+	void whenPropertiesHeadersIsNotSetThenUseOtlpPropertiesHeadersAsFallback() {
+		this.otlpProperties.getHeaders().put("common-header", "common-value");
+		assertThat(createAdapter().headers()).containsEntry("common-header", "common-value");
+	}
+
+	@Test
+	void whenPropertiesHeadersIsSetThenMergeWithOtlpPropertiesHeaders() {
+		this.otlpProperties.getHeaders().put("common-header", "common-value");
+		this.properties.setHeaders(Map.of("signal-header", "signal-value"));
+		assertThat(createAdapter().headers()).containsEntry("common-header", "common-value")
+			.containsEntry("signal-header", "signal-value");
+	}
+
+	@Test
+	void whenPropertiesUrlIsNotSetThenUseOtlpPropertiesEndpointAsFallbackWithAppendix() {
+		this.otlpProperties.setEndpoint("http://common-endpoint:4318");
+		assertThat(createAdapter().url()).isEqualTo("http://common-endpoint:4318/v1/metrics");
+	}
+
+	@Test
+	void whenPropertiesUrlIsNotSetThenUseOtlpPropertiesEndpointAsFallbackWithAppendixAndTrailingSlash() {
+		this.otlpProperties.setEndpoint("http://common-endpoint:4318/");
+		assertThat(createAdapter().url()).isEqualTo("http://common-endpoint:4318/v1/metrics");
+	}
+
+	@Test
+	void whenPropertiesUrlIsSetThenItOverridesOtlpPropertiesEndpoint() {
+		this.otlpProperties.setEndpoint("http://common-endpoint:4318");
+		this.properties.setUrl("http://signal-endpoint:4318/custom/metrics");
+		assertThat(createAdapter().url()).isEqualTo("http://signal-endpoint:4318/custom/metrics");
 	}
 
 }

module/spring-boot-micrometer-tracing-opentelemetry/src/main/java/org/springframework/boot/micrometer/tracing/opentelemetry/autoconfigure/otlp/OtlpTracingAutoConfiguration.java

@@ -26,6 +26,7 @@
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.boot.opentelemetry.autoconfigure.OtlpProperties;
 import org.springframework.context.annotation.Import;
 
 /**
@@ -48,7 +49,7 @@
  */
 @AutoConfiguration
 @ConditionalOnClass({ OtelTracer.class, SdkTracerProvider.class, OpenTelemetry.class, OtlpHttpSpanExporter.class })
-@EnableConfigurationProperties(OtlpTracingProperties.class)
+@EnableConfigurationProperties({ OtlpTracingProperties.class, OtlpProperties.class })
 @Import({ OtlpTracingConfigurations.ConnectionDetails.class, OtlpTracingConfigurations.Exporters.class })
 public final class OtlpTracingAutoConfiguration {