Add checks for exemplars in metrics

Covers QUARKUS-5424

monitoring/opentelemetry-reactive/src/test/java/io/quarkus/ts/opentelemetry/reactive/MetricsIT.java

@@ -0,0 +1,106 @@
+package io.quarkus.ts.opentelemetry.reactive;
+
+import static io.quarkus.test.bootstrap.Protocol.HTTP;
+import static io.restassured.RestAssured.given;
+import static org.awaitility.Awaitility.await;
+import static org.hamcrest.text.IsEqualIgnoringCase.equalToIgnoringCase;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+
+import org.apache.http.HttpStatus;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Tag;
+import org.junit.jupiter.api.Test;
+
+import io.quarkus.test.bootstrap.RestService;
+import io.quarkus.test.scenarios.QuarkusScenario;
+import io.quarkus.test.services.Dependency;
+import io.quarkus.test.services.QuarkusApplication;
+import io.restassured.response.Response;
+
+@QuarkusScenario
+public class MetricsIT {
+    private static final String OTEL_PING_SERVICE_NAME = "pingservice";
+
+    @QuarkusApplication(classes = { PongResource.class, SchedulerResource.class,
+            SchedulerService.class }, properties = "pong.properties")
+    static final RestService pongservice = new RestService()
+            .withProperty("quarkus.application.name", "pongservice");
+
+    @QuarkusApplication(classes = { PingResource.class, PingPongService.class, AdminResource.class }, dependencies = {
+            // Required for metrics. TODO: replace when OTLP gets its own metrics provider
+            @Dependency(artifactId = "quarkus-micrometer-registry-prometheus")
+    })
+    static final RestService pingservice = new RestService()
+            .withProperty("pongservice.url", () -> pongservice.getURI(HTTP).getRestAssuredStyleUri())
+            .withProperty("pongservice.port", () -> Integer.toString(pongservice.getURI(HTTP).getPort()))
+            // verify OTEL service name has priority over default Quarkus application name
+            .withProperty("quarkus.otel.service.name", OTEL_PING_SERVICE_NAME);
+
+    @BeforeAll
+    static void beforeAll() {
+        pingPongRequest();
+        pingPongRequest();
+    }
+
+    private static void pingPongRequest() {
+        given().when()
+                .get(pingservice.getURI(HTTP).withPath("/ping/pong").toString())
+                .then()
+                .statusCode(HttpStatus.SC_OK).body(equalToIgnoringCase("ping pong"));
+    }
+
+    @Test
+    @Tag("QUARKUS-5424")
+    public void testExemplars() {
+        await().ignoreExceptions().atMost(30, TimeUnit.SECONDS)
+                .pollInterval(5, TimeUnit.SECONDS)
+                .untilAsserted(() -> {
+                    Response response = pingservice.given().get("/q/metrics");
+                    assertEquals(HttpStatus.SC_OK, response.statusCode());
+                    final String metricName = "http_server_requests_seconds_count";
+                    final String body = response.body().asString();
+                    String metric = Arrays.stream(body.split("\n"))
+                            .filter(line -> line.startsWith(metricName))
+                            .findFirst()
+                            .orElseThrow(() -> new AssertionError(metricName + " was not found in " + body));
+                    String[] content = metric.split(" ");
+                    assertEquals(6, content.length, "Some values are missing from " + metric);
+                    assertEquals("""
+                            http_server_requests_seconds_count{method="GET",outcome="SUCCESS",status="200",uri="/ping/pong"}
+                            """.strip(), content[0]);
+
+                    assertEquals("2.0", content[1], "Amount of events is wrong");
+                    assertEquals("#", content[2], "Unexpected exemplar separator!");
+                    assertTrue(content[3].contains("span_id"), "Exemplar doesn't contain span ID");
+                    assertTrue(content[3].contains("trace_id"), "Exemplar doesn't contain trace ID");
+                    assertEquals("1.0", content[4], "Unexpected exemplar value!");
+                });
+    }
+
+    @Test
+    public void testNetty() {
+        await().ignoreExceptions().atMost(30, TimeUnit.SECONDS)
+                .pollInterval(5, TimeUnit.SECONDS)
+                .untilAsserted(() -> {
+                    Response response = pingservice.given().get("/q/metrics");
+                    assertEquals(HttpStatus.SC_OK, response.statusCode());
+                    final String metricName = "netty_allocator_memory_used";
+                    final String body = response.body().asString();
+                    List<String> metrics = Arrays.stream(body.split("\n"))
+                            .filter(line -> line.startsWith(metricName))
+                            .toList();
+                    assertNotEquals(0, metrics.size(), "No Netty metrics");
+                    for (String metric : metrics) {
+                        String type = metric.split(" ")[0];
+                        List<String> params = Arrays.asList(type.substring(type.indexOf('{'), type.indexOf('}')).split(","));
+
+                    }
+                });
+    }
+}

monitoring/opentelemetry-reactive/src/test/java/io/quarkus/ts/opentelemetry/reactive/OpentelemetryReactiveIT.java

@@ -10,14 +10,14 @@
 import static org.hamcrest.Matchers.greaterThanOrEqualTo;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.text.IsEqualIgnoringCase.equalToIgnoringCase;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.time.Duration;
 import java.util.ArrayList;
 import java.util.concurrent.TimeUnit;
 
 import org.apache.http.HttpStatus;
 import org.hamcrest.Matcher;
-import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
 import io.quarkus.test.bootstrap.JaegerService;
@@ -69,8 +69,8 @@ public void testContextPropagation() {
             ArrayList<String> spanKinds = resp.body().path(
                     "data[0].spans.findAll { it.operationName == '%s' }.tags.flatten().findAll { it.key == 'span.kind' }.value.flatten()",
                     "GET /hello");
-            Assertions.assertTrue(spanKinds.contains("client"));
-            Assertions.assertTrue(spanKinds.contains("server"));
+            assertTrue(spanKinds.contains("client"));
+            assertTrue(spanKinds.contains("server"));
         });
     }
 
@@ -108,7 +108,7 @@ public void testSchedulerTracing() {
                 .extract()
                 .body()
                 .asString());
-        Assertions.assertTrue(invocations >= 2);
+        assertTrue(invocations >= 2);
     }
 
     public void whenDoPingPongRequest() {