8877 Make KeycloakMetricsHandler aware of context-path

Adapt KeycloakMetricsHandler to consider custom relative paths via `kc.http.relative-path`
or --http-relative-path=/auth. Previously only the fixed path /metrics was allowed which did not work
with custom context-paths.

- Adapted KeycloakProcessor to Pedros proposal from 0b28d71dd0
- Removed unnecessary KeycloakMetricsHandler
- Added MetricsDistTest

Fixes #8877

quarkus/deployment/src/main/java/org/keycloak/quarkus/deployment/KeycloakProcessor.java

@@ -67,6 +67,7 @@ import io.quarkus.hibernate.orm.deployment.PersistenceXmlDescriptorBuildItem;
 import io.quarkus.resteasy.server.common.deployment.ResteasyDeploymentCustomizerBuildItem;
 import io.quarkus.runtime.LaunchMode;
 import io.quarkus.smallrye.health.runtime.SmallRyeHealthHandler;
+import io.quarkus.vertx.http.deployment.NonApplicationRootPathBuildItem;
 import io.quarkus.vertx.http.deployment.RouteBuildItem;
 import io.vertx.core.Handler;
 import io.vertx.ext.web.RoutingContext;
@@ -117,7 +118,6 @@ import org.keycloak.representations.provider.ScriptProviderDescriptor;
 import org.keycloak.representations.provider.ScriptProviderMetadata;
 import org.keycloak.quarkus.runtime.integration.web.NotFoundHandler;
 import org.keycloak.services.ServicesLogger;
-import org.keycloak.quarkus.runtime.services.health.KeycloakMetricsHandler;
 import org.keycloak.theme.FolderThemeProviderFactory;
 import org.keycloak.transaction.JBossJtaTransactionManagerLookup;
 import org.keycloak.quarkus.runtime.Environment;
@@ -132,6 +132,7 @@ class KeycloakProcessor {
 
     private static final String JAR_FILE_SEPARATOR = "!/";
     private static final String DEFAULT_HEALTH_ENDPOINT = "/health";
+    private static final String DEFAULT_METRICS_ENDPOINT = "/metrics";
     private static final Map<String, Function<ScriptProviderMetadata, ProviderFactory>> DEPLOYEABLE_SCRIPT_PROVIDERS = new HashMap<>();
     private static final String KEYCLOAK_SCRIPTS_JSON_PATH = "META-INF/keycloak-scripts.json";
 
@@ -344,14 +345,16 @@ class KeycloakProcessor {
      *
      * @param routes
      */
+    @Record(ExecutionTime.STATIC_INIT)
     @BuildStep
-    void initializeMetrics(BuildProducer<RouteBuildItem> routes) {
+    void initializeMetrics(KeycloakRecorder recorder, BuildProducer<RouteBuildItem> routes, NonApplicationRootPathBuildItem nonAppRootPath) {
         Handler<RoutingContext> healthHandler;
         Handler<RoutingContext> metricsHandler;
 
         if (isMetricsEnabled()) {
             healthHandler = new SmallRyeHealthHandler();
-            metricsHandler = new KeycloakMetricsHandler();
+            String rootPath = nonAppRootPath.getNormalizedHttpRootPath();
+            metricsHandler = recorder.createMetricsHandler(rootPath.concat(DEFAULT_METRICS_ENDPOINT).replace("//", "/"));
         } else {
             healthHandler = new NotFoundHandler();
             metricsHandler = new NotFoundHandler();
@@ -360,7 +363,7 @@ class KeycloakProcessor {
         routes.produce(RouteBuildItem.builder().route(DEFAULT_HEALTH_ENDPOINT).handler(healthHandler).build());
         routes.produce(RouteBuildItem.builder().route(DEFAULT_HEALTH_ENDPOINT.concat("/live")).handler(healthHandler).build());
         routes.produce(RouteBuildItem.builder().route(DEFAULT_HEALTH_ENDPOINT.concat("/ready")).handler(healthHandler).build());
-        routes.produce(RouteBuildItem.builder().route(KeycloakMetricsHandler.DEFAULT_METRICS_ENDPOINT).handler(metricsHandler).build());
+        routes.produce(RouteBuildItem.builder().route(DEFAULT_METRICS_ENDPOINT).handler(metricsHandler).build());
     }
 
     @BuildStep

quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/KeycloakRecorder.java

@@ -27,6 +27,9 @@ import org.infinispan.configuration.parsing.ConfigurationBuilderHolder;
 import org.infinispan.configuration.parsing.ParserRegistry;
 import org.infinispan.jboss.marshalling.core.JBossUserMarshaller;
 import org.infinispan.manager.DefaultCacheManager;
+import io.quarkus.smallrye.metrics.runtime.SmallRyeMetricsHandler;
+import io.vertx.core.Handler;
+import io.vertx.ext.web.RoutingContext;
 import org.keycloak.common.Profile;
 import org.keycloak.quarkus.runtime.configuration.Configuration;
 import org.keycloak.quarkus.runtime.integration.QuarkusKeycloakSessionFactory;
@@ -152,4 +155,10 @@ public class KeycloakRecorder {
             }
         });
     }
+
+    public Handler<RoutingContext> createMetricsHandler(String path) {
+        SmallRyeMetricsHandler metricsHandler = new SmallRyeMetricsHandler();
+        metricsHandler.setMetricsPath(path);
+        return metricsHandler;
+    }
 }

quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/services/health/KeycloakMetricsHandler.java

@@ -1,29 +0,0 @@
-/*
- * Copyright 2020 Red Hat, Inc. and/or its affiliates
- * and other contributors as indicated by the @author tags.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.keycloak.quarkus.runtime.services.health;
-
-import io.quarkus.smallrye.metrics.runtime.SmallRyeMetricsHandler;
-
-public class KeycloakMetricsHandler extends SmallRyeMetricsHandler {
-
-    public static final String DEFAULT_METRICS_ENDPOINT = "/metrics";
-
-    public KeycloakMetricsHandler() {
-        setMetricsPath(DEFAULT_METRICS_ENDPOINT);
-    }
-}

quarkus/tests/integration/src/test/java/org/keycloak/it/cli/dist/MetricsDistTest.java

@@ -20,7 +20,6 @@ package org.keycloak.it.cli.dist;
 import static io.restassured.RestAssured.when;
 import static org.hamcrest.Matchers.containsString;
 
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 import org.keycloak.it.junit5.extension.DistributionTest;
 
@@ -37,7 +36,6 @@ public class MetricsDistTest {
                 .body(containsString("base_gc_total"));
     }
 
-    @Disabled("https://github.com/keycloak/keycloak/pull/8878")
     @Test
     @Launch({ "start-dev", "--http-relative-path=/auth", "--metrics-enabled=true" })
     void testMetricsEndpointUsingRelativePath() {