From 4125d8c9adbfc125aa8a36696489e595a3bce4d4 Mon Sep 17 00:00:00 2001
From: Emre Dincturk <74370953+mrdnctrk@users.noreply.github.com>
Date: Fri, 19 Apr 2024 17:43:19 -0400
Subject: [PATCH] added otel span for interceptors (#5853)

---
 hapi-fhir-base/pom.xml                        |  5 +++++
 .../executor/BaseInterceptorService.java      | 17 ++++++++++++++++-
 ...-opentelemetry-spans-for-interceptors.yaml |  6 ++++++
 pom.xml                                       | 19 +++++++++++++++++++
 4 files changed, 46 insertions(+), 1 deletion(-)
 create mode 100644 hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/7_2_0/5855-opentelemetry-spans-for-interceptors.yaml

diff --git a/hapi-fhir-base/pom.xml b/hapi-fhir-base/pom.xml
index 1db4476b4d3..c5ec6eee1f1 100644
--- a/hapi-fhir-base/pom.xml
+++ b/hapi-fhir-base/pom.xml
@@ -138,6 +138,11 @@
 			<artifactId>system-stubs-jupiter</artifactId>
 			<scope>test</scope>
 		</dependency>
+		<!-- OpenTelemetry -->
+		<dependency>
+			<groupId>io.opentelemetry</groupId>
+			<artifactId>opentelemetry-api</artifactId>
+		</dependency>
 	</dependencies>
 
 	<build>
diff --git a/hapi-fhir-base/src/main/java/ca/uhn/fhir/interceptor/executor/BaseInterceptorService.java b/hapi-fhir-base/src/main/java/ca/uhn/fhir/interceptor/executor/BaseInterceptorService.java
index d0ba36e44c3..22a196850ea 100644
--- a/hapi-fhir-base/src/main/java/ca/uhn/fhir/interceptor/executor/BaseInterceptorService.java
+++ b/hapi-fhir-base/src/main/java/ca/uhn/fhir/interceptor/executor/BaseInterceptorService.java
@@ -31,6 +31,8 @@ import ca.uhn.fhir.util.ReflectionUtil;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.collect.ArrayListMultimap;
 import com.google.common.collect.ListMultimap;
+import io.opentelemetry.api.trace.Span;
+import io.opentelemetry.instrumentation.annotations.WithSpan;
 import jakarta.annotation.Nonnull;
 import jakarta.annotation.Nullable;
 import org.apache.commons.lang3.Validate;
@@ -547,7 +549,7 @@ public abstract class BaseInterceptorService<POINTCUT extends Enum<POINTCUT> & I
 
 			// Invoke the method
 			try {
-				return myMethod.invoke(getInterceptor(), args);
+				return invokeMethod(args);
 			} catch (InvocationTargetException e) {
 				Throwable targetException = e.getTargetException();
 				if (myPointcut.isShouldLogAndSwallowException(targetException)) {
@@ -566,6 +568,19 @@ public abstract class BaseInterceptorService<POINTCUT extends Enum<POINTCUT> & I
 				throw new InternalErrorException(Msg.code(1911) + e);
 			}
 		}
+
+		@WithSpan("hapifhir.interceptor")
+		private Object invokeMethod(Object[] args) throws InvocationTargetException, IllegalAccessException {
+			// Add attributes to the opentelemetry span
+			Span currentSpan = Span.current();
+			currentSpan.setAttribute("hapifhir.interceptor.pointcut_name", myPointcut.name());
+			currentSpan.setAttribute(
+					"hapifhir.interceptor.class_name",
+					myMethod.getDeclaringClass().getName());
+			currentSpan.setAttribute("hapifhir.interceptor.method_name", myMethod.getName());
+
+			return myMethod.invoke(getInterceptor(), args);
+		}
 	}
 
 	protected class HookDescriptor {
diff --git a/hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/7_2_0/5855-opentelemetry-spans-for-interceptors.yaml b/hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/7_2_0/5855-opentelemetry-spans-for-interceptors.yaml
new file mode 100644
index 00000000000..52e71439b05
--- /dev/null
+++ b/hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/7_2_0/5855-opentelemetry-spans-for-interceptors.yaml
@@ -0,0 +1,6 @@
+---
+type: add
+issue: 5855
+title: "If using an OpenTelemetry agent, a span is now generated for each interceptor method call. The span is named 
+as 'hapifhir.interceptor' and it has the following attributes about the interceptor:
+'hapifhir.interceptor.pointcut_name','hapifhir.interceptor.class_name', 'hapifhir.interceptor.method_name'"
diff --git a/pom.xml b/pom.xml
index c6ef616a573..0ffabdf9385 100644
--- a/pom.xml
+++ b/pom.xml
@@ -165,6 +165,11 @@
 			<artifactId>mockito-junit-jupiter</artifactId>
 			<scope>test</scope>
 		</dependency>
+		<!-- OpenTelemetry Annotations-->
+		<dependency>
+			<groupId>io.opentelemetry.instrumentation</groupId>
+			<artifactId>opentelemetry-instrumentation-annotations</artifactId>
+		</dependency>
 	</dependencies>
 
 	<developers>
@@ -977,6 +982,7 @@
 		<maven_assembly_plugin_version>3.3.0</maven_assembly_plugin_version>
 		<maven_license_plugin_version>1.8</maven_license_plugin_version>
 		<okhttp_version>4.10.0</okhttp_version>
+		<otel.version>1.32.0</otel.version> <!-- BOM Version -->
 		<poi_version>4.1.2</poi_version>
 		<poi_ooxml_schemas_version>1.4</poi_ooxml_schemas_version>
 		<resteasy_version>6.2.5.Final</resteasy_version>
@@ -2264,6 +2270,19 @@
 				<scope>provided</scope>
 				<optional>true</optional>
 			</dependency>
+			<!-- OpenTelemetry -->
+			<dependency>
+				<groupId>io.opentelemetry</groupId>
+				<artifactId>opentelemetry-bom</artifactId>
+				<version>${otel.version}</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+			<dependency>
+				<groupId>io.opentelemetry.instrumentation</groupId>
+				<artifactId>opentelemetry-instrumentation-annotations</artifactId>
+				<version>${otel.version}</version>
+			</dependency>
 		</dependencies>
 	</dependencyManagement>