CAMEL-21118: Adds rest-cxf-opentelemetry (#142)

README.adoc

@@ -27,7 +27,7 @@ readme's instructions.
 === Examples
 
 // examples: START
-Number of Examples: 58 (0 deprecated)
+Number of Examples: 59 (0 deprecated)
 
 [width="100%",cols="4,2,4",options="header"]
 |===
@@ -77,6 +77,8 @@ Number of Examples: 58 (0 deprecated)
 
 | link:master/readme.adoc[Master] (master) | Clustering | An example showing how to work with Camel's Master component and Spring Boot
 
+| link:rest-cxf-opentelemetry/README.adoc[Rest Cxf Opentelemetry] (rest-cxf-opentelemetry) | CXF | An example showing Camel REST using CXF and OpenTelemetry with Spring Boot
+
 | link:soap-cxf/README.adoc[Soap Cxf] (soap-cxf) | CXF | An example showing the Camel SOAP CXF
 
 | link:arangodb/README.adoc[Arangodb] (arangodb) | Database | An example showing the Camel ArangoDb component with Spring Boot

pom.xml

@@ -69,6 +69,7 @@
 		<module>reactive-streams</module>
 		<module>resilience4j</module>
 		<module>rest-cxf</module>
+		<module>rest-cxf-opentelemetry</module>
 		<module>rest-openapi</module>
 		<module>rest-openapi-simple</module>
 		<module>rest-openapi-springdoc</module>

rest-cxf-opentelemetry/README.adoc

@@ -0,0 +1,145 @@
+== Spring Boot Example with Camel exposing REST services using Apache CXF, collecting distributed tracing using OpenTelemetry
+
+=== Introduction
+
+This example illustrates how to use https://projects.spring.io/spring-boot/[Spring Boot] with http://camel.apache.org[Camel] and https://cxf.apache.org/[Apache CXF] implementing REST services using bottom-up approach.
+
+If you are using REST services directly from Camel and you want to use https://opentelemetry.io/[OpenTelemetry] please refer to link:../opentelemetry/README.adoc[the dedicated example]
+
+There are 3 services which communicate each other, starting from the `random` service:
+
+- random: the main service, exposes the entry point REST service and store the results
+- even: the service that verifies the even numbers
+- odd: the service that verifies the odd numbers
+
+moreover there is a common module containing common classes
+
+image::docs/overview.png[]
+
+=== Build
+
+You can build this example using the following command; it will also download the OpenTelemetry agent used to instrument the applications:
+
+    $ mvn package -Potel-agent
+
+=== Run
+
+Run docker-compose to start all the needed services:
+
+    $ docker-compose -f containers/docker-compose.yml up -d
+
+the command runs:
+
+- https://github.com/minio/minio[minio] as application storage
+- https://github.com/open-telemetry/opentelemetry-collector[opentelemetry-collector] to receive the generated Trace/Span
+- https://github.com/jaegertracing/jaeger[Jaeger] to visualize the traces
+
+Run each services on separated terminals:
+
+    $ source containers/env.sh \
+        && java -javaagent:target/opentelemetry-javaagent.jar \
+        -Dotel.service.name=random \
+        -jar rest-cxf-otel-random/target/*.jar
+
+    $ source containers/env.sh \
+        && java -javaagent:target/opentelemetry-javaagent.jar \
+        -Dotel.service.name=even \
+        -Dserver.port=8081 \
+        -jar rest-cxf-otel-even/target/*.jar
+
+    $ source containers/env.sh \
+        && java -javaagent:target/opentelemetry-javaagent.jar \
+        -Dotel.service.name=odd \
+        -Dserver.port=8082 \
+        -jar rest-cxf-otel-odd/target/*.jar
+
+After the Spring Boot applications have been started, you can open the following URL in your web browser http://localhost:8080/services/ to access the list of services,  including WADL definition
+
+You can also access the REST endpoint from the command line:
+
+i.e. to generate 5 random numbers run:
+
+    $ curl -X POST http://localhost:8080/services/api/play/5 -s | jq .
+
+The command will produce an output like:
+
+[source,json]
+----
+{
+  "result": {
+    "ODD": [
+      {
+        "number": 229,
+        "type": "ODD"
+      },
+      {
+        "number": 585,
+        "type": "ODD"
+      }
+    ],
+    "EVEN": [
+      {
+        "number": 648,
+        "type": "EVEN"
+      },
+      {
+        "number": 670,
+        "type": "EVEN"
+      },
+      {
+        "number": 846,
+        "type": "EVEN"
+      }
+    ]
+  },
+  "evenCount": 3,
+  "oddCount": 2
+}
+----
+
+Now in the Jaeger UI http://localhost:16686 the traces will be available, both from Camel and from CXF instrumentation
+
+image::docs/jaeger.png[]
+
+The services can be stopped pressing `[CTRL] + [C]` in the shell, and the containers can be stopped with
+
+    $ docker-compose -f containers/docker-compose.yml down
+
+=== Explain the code
+
+The dependency `org.apache.cxf:cxf-integration-tracing-opentelemetry` provides `org.apache.cxf.tracing.opentelemetry.jaxrs.OpenTelemetryFeature` that instruments the OpenTelemetry API implemented in the java agent.
+
+The feature is injected in the Spring context
+
+[source,java]
+----
+include::rest-cxf-otel-common/src/main/java/org/apache/camel/example/springboot/cxf/otel/CxfConfig.java[lines=35..38]
+----
+
+and then it is configured in the Camel route as provider in the `cxfrs` endpoint
+
+[source,java]
+----
+include::rest-cxf-otel-random/src/main/java/org/apache/camel/example/springboot/cxf/otel/CamelRouter.java[lines=51]
+----
+
+When the feature is enabled it is possible to add custom tags or logs using `TracerContext` from CXF
+[source,java]
+----
+include::rest-cxf-otel-random/src/main/java/org/apache/camel/example/springboot/cxf/otel/RandomService.java[lines=56..58]
+----
+
+[source,java]
+----
+include::rest-cxf-otel-random/src/main/java/org/apache/camel/example/springboot/cxf/otel/RandomServiceImpl.java[lines=43..45]
+----
+
+=== Help and contributions
+
+If you hit any problem using Camel or have some feedback, then please
+https://camel.apache.org/community/support/[let us know].
+
+We also love contributors, so
+https://camel.apache.org/community/contributing/[get involved] :-)
+
+The Camel riders!

rest-cxf-opentelemetry/containers/docker-compose.yml

@@ -0,0 +1,35 @@
+version: "3.9"
+
+services:
+
+  minio:
+    image: "quay.io/minio/minio:latest"
+    environment:
+      - MINIO_ROOT_USER=admin
+      - MINIO_ROOT_PASSWORD=admin123
+    ports:
+      - "9000:9000"
+      - "9001:9001"
+    command:
+      - server
+      - /data
+      - --console-address
+      - :9001
+
+  otel-collector:
+    image: otel/opentelemetry-collector:latest
+    command:
+      - --config=/etc/otelcol-cont/otel-collector.yml
+    volumes:
+      - ./otel-collector.yml:/etc/otelcol-cont/otel-collector.yml
+    ports:
+      - "4318:4318" # OTLP http receiver
+      - "4317:4317" # OTLP grpc receiver
+    depends_on:
+      - jaeger-all-in-one
+
+  jaeger-all-in-one:
+    image: quay.io/jaegertracing/all-in-one:latest
+    restart: always
+    ports:
+      - "16686:16686"

rest-cxf-opentelemetry/containers/env.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/bash
+
+export OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4317
+export OTEL_EXPORTER_OTLP_TRACES_ENDPOINT=http://localhost:4318/v1/traces
+export OTEL_TRACES_EXPORTER=otlp
+export OTEL_METRICS_EXPORTER=none
+export OTEL_LOGS_EXPORTER=none
+#export OTEL_JAVAAGENT_DEBUG=true

rest-cxf-opentelemetry/containers/otel-collector.yml

@@ -0,0 +1,25 @@
+receivers:
+  otlp:
+    protocols:
+      grpc:
+        endpoint: 0.0.0.0:4317
+      http:
+        endpoint: 0.0.0.0:4318
+
+processors:
+  batch:
+
+exporters:
+  debug:
+    verbosity: detailed
+  otlp/jaeger:
+    endpoint: jaeger-all-in-one:4317
+    tls:
+      insecure: true
+
+service:
+  pipelines:
+    traces:
+      receivers: [otlp]
+      processors: [batch]
+      exporters: [debug,otlp/jaeger]