Migrate Metrics extension to a vert.x route

extensions/smallrye-metrics/deployment/pom.xml

@@ -20,7 +20,7 @@
         </dependency>
         <dependency>
             <groupId>io.quarkus</groupId>
-            <artifactId>quarkus-undertow-deployment</artifactId>
+            <artifactId>quarkus-vertx-http-deployment</artifactId>
         </dependency>
         <dependency>
             <groupId>io.quarkus</groupId>

extensions/smallrye-metrics/deployment/src/main/java/io/quarkus/smallrye/metrics/deployment/SmallRyeMetricsProcessor.java

@@ -13,6 +13,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.function.Function;
 
 import javax.enterprise.context.Dependent;
 
@@ -31,6 +32,7 @@
 import io.quarkus.arc.deployment.AutoInjectAnnotationBuildItem;
 import io.quarkus.arc.deployment.BeanArchiveIndexBuildItem;
 import io.quarkus.arc.deployment.BeanContainerBuildItem;
+import io.quarkus.arc.deployment.UnremovableBeanBuildItem;
 import io.quarkus.arc.processor.AnnotationsTransformer;
 import io.quarkus.arc.processor.BuiltinScope;
 import io.quarkus.deployment.annotations.BuildProducer;
@@ -45,8 +47,8 @@
 import io.quarkus.smallrye.metrics.deployment.jandex.JandexBeanInfoAdapter;
 import io.quarkus.smallrye.metrics.deployment.jandex.JandexMemberInfoAdapter;
 import io.quarkus.smallrye.metrics.runtime.SmallRyeMetricsRecorder;
-import io.quarkus.smallrye.metrics.runtime.SmallRyeMetricsServlet;
-import io.quarkus.undertow.deployment.ServletBuildItem;
+import io.quarkus.vertx.http.deployment.RouteBuildItem;
+import io.quarkus.vertx.http.runtime.HandlerType;
 import io.smallrye.metrics.MetricProducer;
 import io.smallrye.metrics.MetricRegistries;
 import io.smallrye.metrics.MetricsRequestHandler;
@@ -57,6 +59,8 @@
 import io.smallrye.metrics.interceptors.MetricNameFactory;
 import io.smallrye.metrics.interceptors.MetricsInterceptor;
 import io.smallrye.metrics.interceptors.TimedInterceptor;
+import io.vertx.ext.web.Route;
+import io.vertx.ext.web.Router;
 
 public class SmallRyeMetricsProcessor {
     private static final Logger LOGGER = Logger.getLogger("io.quarkus.smallrye.metrics.deployment.SmallRyeMetricsProcessor");
@@ -65,7 +69,7 @@ public class SmallRyeMetricsProcessor {
     static final class SmallRyeMetricsConfig {
 
         /**
-         * The path to the metrics Servlet.
+         * The path to the metrics handler.
          */
         @ConfigItem(defaultValue = "/metrics")
         String path;
@@ -74,16 +78,16 @@ static final class SmallRyeMetricsConfig {
     SmallRyeMetricsConfig metrics;
 
     @BuildStep
-    ServletBuildItem createServlet() {
-        ServletBuildItem servletBuildItem = ServletBuildItem.builder("metrics", SmallRyeMetricsServlet.class.getName())
-                .addMapping(metrics.path + (metrics.path.endsWith("/") ? "*" : "/*"))
-                .addInitParam("metrics.path", metrics.path)
-                .build();
-        return servletBuildItem;
+    @Record(STATIC_INIT)
+    void createRoute(BuildProducer<RouteBuildItem> routes,
+            SmallRyeMetricsRecorder recorder) {
+        Function<Router, Route> route = recorder.route(metrics.path + (metrics.path.endsWith("/") ? "*" : "/*"));
+        routes.produce(new RouteBuildItem(route, recorder.handler(metrics.path), HandlerType.BLOCKING));
     }
 
     @BuildStep
-    void beans(BuildProducer<AdditionalBeanBuildItem> additionalBeans) {
+    void beans(BuildProducer<AdditionalBeanBuildItem> additionalBeans,
+            BuildProducer<UnremovableBeanBuildItem> unremovableBeans) {
         additionalBeans.produce(new AdditionalBeanBuildItem(MetricProducer.class,
                 MetricNameFactory.class,
                 MetricRegistries.class,
@@ -92,8 +96,9 @@ void beans(BuildProducer<AdditionalBeanBuildItem> additionalBeans) {
                 ConcurrentGaugeInterceptor.class,
                 CountedInterceptor.class,
                 TimedInterceptor.class,
-                MetricsRequestHandler.class,
-                SmallRyeMetricsServlet.class));
+                MetricsRequestHandler.class));
+        unremovableBeans.produce(new UnremovableBeanBuildItem(
+                new UnremovableBeanBuildItem.BeanClassNameExclusion(MetricsRequestHandler.class.getName())));
     }
 
     @BuildStep

extensions/smallrye-metrics/runtime/pom.xml

@@ -25,7 +25,7 @@
         </dependency>
         <dependency>
             <groupId>io.quarkus</groupId>
-            <artifactId>quarkus-undertow</artifactId>
+            <artifactId>quarkus-vertx-http</artifactId>
         </dependency>
         <dependency>
             <groupId>io.quarkus</groupId>
@@ -35,10 +35,6 @@
             <groupId>io.quarkus</groupId>
             <artifactId>quarkus-jsonp</artifactId>
         </dependency>
-        <dependency>
-            <groupId>org.jboss.spec.javax.servlet</groupId>
-            <artifactId>jboss-servlet-api_4.0_spec</artifactId>
-        </dependency>
     </dependencies>
 
     <build>

extensions/smallrye-metrics/runtime/src/main/java/io/quarkus/smallrye/metrics/runtime/SmallRyeMetricsHandler.java

@@ -0,0 +1,47 @@
+package io.quarkus.smallrye.metrics.runtime;
+
+import java.io.IOException;
+import java.util.stream.Stream;
+
+import javax.enterprise.inject.spi.CDI;
+
+import org.jboss.logging.Logger;
+
+import io.smallrye.metrics.MetricsRequestHandler;
+import io.vertx.core.Handler;
+import io.vertx.core.buffer.Buffer;
+import io.vertx.core.http.HttpServerRequest;
+import io.vertx.core.http.HttpServerResponse;
+import io.vertx.ext.web.RoutingContext;
+
+public class SmallRyeMetricsHandler implements Handler<RoutingContext> {
+
+    private String metricsPath;
+
+    private static final Logger LOGGER = Logger.getLogger(SmallRyeMetricsHandler.class.getName());
+
+    public void setMetricsPath(String metricsPath) {
+        this.metricsPath = metricsPath;
+    }
+
+    @Override
+    public void handle(RoutingContext routingContext) {
+        MetricsRequestHandler internalHandler = CDI.current().select(MetricsRequestHandler.class).get();
+        HttpServerResponse response = routingContext.response();
+        HttpServerRequest request = routingContext.request();
+        Stream<String> acceptHeaders = request.headers().getAll("Accept").stream();
+
+        try {
+            internalHandler.handleRequest(request.path(), metricsPath, request.rawMethod(), acceptHeaders,
+                    (status, message, headers) -> {
+                        response.setStatusCode(status);
+                        headers.forEach(response::putHeader);
+                        response.end(Buffer.buffer(message));
+                    });
+        } catch (IOException e) {
+            response.setStatusCode(503);
+            response.end();
+            LOGGER.error(e);
+        }
+    }
+}

extensions/smallrye-metrics/runtime/src/main/java/io/quarkus/smallrye/metrics/runtime/SmallRyeMetricsRecorder.java

@@ -10,6 +10,7 @@
 import java.lang.management.ThreadMXBean;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.function.Function;
 
 import org.eclipse.microprofile.metrics.Metadata;
 import org.eclipse.microprofile.metrics.MetricRegistry;
@@ -27,6 +28,8 @@
 import io.smallrye.metrics.elementdesc.MemberInfo;
 import io.smallrye.metrics.interceptors.MetricResolver;
 import io.smallrye.metrics.setup.MetricsMetadata;
+import io.vertx.ext.web.Route;
+import io.vertx.ext.web.Router;
 
 @Recorder
 public class SmallRyeMetricsRecorder {
@@ -63,6 +66,21 @@ public class SmallRyeMetricsRecorder {
     private static final String MEMORY_USED_HEAP = "memory.usedHeap";
     private static final String MEMORY_USED_NON_HEAP = "memory.usedNonHeap";
 
+    public Function<Router, Route> route(String name) {
+        return new Function<Router, Route>() {
+            @Override
+            public Route apply(Router router) {
+                return router.route(name);
+            }
+        };
+    }
+
+    public SmallRyeMetricsHandler handler(String metricsPath) {
+        SmallRyeMetricsHandler handler = new SmallRyeMetricsHandler();
+        handler.setMetricsPath(metricsPath);
+        return handler;
+    }
+
     public void registerVendorMetrics(ShutdownContext shutdown) {
         MetricRegistry registry = MetricRegistries.get(MetricRegistry.Type.VENDOR);
         List<String> names = new ArrayList<>();