Metrics gauge example fixed

examples/mp-metrics-counted/src/main/java/org/superbiz/rest/WeatherService.java

@@ -18,7 +18,8 @@ public class WeatherService {
     @Path("/day/status")
     @Counted(monotonic = true, name = "weather_day_status", absolute = true,
             displayName = "Weather Day Status",
-            description = "This metric shows the weather status of the day.")
+            description = "This metric shows the weather status of the day.",
+            tags = {"weather=day"})
     @GET
     @Produces(MediaType.TEXT_PLAIN)
     public String dayStatus() {

examples/mp-metrics-gauge/README.adoc

@@ -0,0 +1,125 @@
+= MicroProfile Metrics Gauge
+
+:index-group: MicroProfile
+:jbake-type: page
+:jbake-status: published
+
+This is an example on how to use MicroProfile metrics in TomEE.
+
+.Run the application:
+ mvn clean install tomee:run
+
+Within the application there is an endpoint that will give you the weather temperature in celsius for the day.
+
+.For the day temperature call:
+ GET http://localhost:8080/mp-metrics-gauge/weather/day/temperature
+
+.Response:
+ 30
+
+[discrete]
+==== Gauge Feature
+
+MicroProfile metrics has a gauge feature. The gauge value and type is equal to the annotated method return value and type.
+
+To use this feature you need to annotate the JAX-RS resource method with @Gauge.
+
+....
+@Path("/weather")
+@Produces(MediaType.APPLICATION_JSON)
+@Consumes(MediaType.APPLICATION_JSON)
+@ApplicationScoped
+public class WeatherService {
+
+    @Path("/day/temperature")
+    @Gauge(name = "weather_day_temperature", absolute = true, unit = "celsius",
+            displayName = "Weather Day Temperature",
+            description = "This metric shows the day temperature.",
+            tags = {"weather=temperature"})
+    @GET
+    @Produces(MediaType.TEXT_PLAIN)
+    public Integer dayTemperature() {
+        return 30;
+    }
+}
+....
+
+There are some configurations, as part of @Gauge, that you need to know:
+
+*String name*
+Optional. Sets the name of the metric. If not explicitly given the name of the annotated object is used.
+
+*boolean absolute*
+If true, uses the given name as the absolute name of the metric. If false, prepends the package name and class name before the given name. Default value is false.
+
+*String displayName*
+Optional. A human-readable display name for metadata.
+
+*String description*
+Optional. A description of the metric.
+
+*String[] tags*
+Optional. Array of Strings in the +++<key>+++=+++<value>+++format to supply special tags to a metric.+++</value>++++++</key>+++
+
+*String unit*
+Unit of the metric. Check the MetricUnits class for a set of pre-defined units.
+
+[discrete]
+==== Metric data
+
+Check the gauge metric doing a _GET_ request:
+
+.Prometheus format:
+ GET http://localhost:8080/mp-metrics-gauge/metrics/application/weather_day_temperature
+
+.Response:
+ # TYPE application:weather_day_temperature_celsius gauge
+ application:weather_day_temperature_celsius{weather="temperature"} 30.0
+
+[discrete]
+===== JSON Format:
+
+For json format add the header _Accept=application/json_ to the request.
+
+ {
+     "weather_day_temperature": 30
+ }
+
+[discrete]
+==== Metric metadata
+
+A metric will have a metadata so you can know more information about it, like displayName, description, tags e etc.
+
+Check the metric metadata doing a _OPTIONS_ request:
+
+.Request
+ OPTIONS http://localhost:8080/mp-metrics-gauge/metrics/application/weather_day_temperature
+
+.Response:
+ {
+     "weather_day_temperature": {
+         "unit": "celsius",
+         "displayName": "Weather Day Temperature",
+         "name": "weather_day_temperature",
+         "typeRaw": "GAUGE",
+         "description": "This metric shows the day temperature.",
+         "type": "gauge",
+         "value": {
+             "unit": "celsius",
+             "displayName": "Weather Day Temperature",
+             "name": "weather_day_temperature",
+             "tagsAsString": "weather=\"temperature\"",
+             "typeRaw": "GAUGE",
+             "description": "This metric shows the day temperature.",
+             "type": "gauge",
+             "reusable": false,
+             "tags": {
+                 "weather": "temperature"
+             }
+         },
+         "reusable": false,
+         "tags": "weather=temperature"
+     }
+ }
+
+You can also try it out using the WeatherServiceTest.java available in the project.

examples/mp-metrics-gauge/pom.xml

@@ -0,0 +1,69 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>examples</artifactId>
+        <groupId>org.apache.tomee</groupId>
+        <version>8.0.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>mp-metrics-gauge</artifactId>
+    <packaging>war</packaging>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.tomee</groupId>
+            <artifactId>javaee-api</artifactId>
+            <version>${version.javaee-api}</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.eclipse.microprofile.metrics</groupId>
+            <artifactId>microprofile-metrics-api</artifactId>
+            <version>${microprofile.metrics.version}</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.tomee</groupId>
+            <artifactId>openejb-cxf-rs</artifactId>
+            <version>${tomee.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.jboss.arquillian.junit</groupId>
+            <artifactId>arquillian-junit-container</artifactId>
+            <version>${version.arquillian.bom}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.tomee</groupId>
+            <artifactId>arquillian-tomee-remote</artifactId>
+            <version>${tomee.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.tomee</groupId>
+            <artifactId>apache-tomee</artifactId>
+            <version>${tomee.version}</version>
+            <type>zip</type>
+            <classifier>microprofile</classifier>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.tomee.maven</groupId>
+                <artifactId>tomee-maven-plugin</artifactId>
+                <version>${project.version}</version>
+                <configuration>
+                    <tomeeClassifier>microprofile</tomeeClassifier>
+                    <context>${artifactId}</context>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+</project>

examples/mp-metrics-gauge/src/main/java/org/superbiz/rest/WeatherService.java

@@ -0,0 +1,28 @@
+package org.superbiz.rest;
+
+import org.eclipse.microprofile.metrics.annotation.Gauge;
+
+import javax.enterprise.context.ApplicationScoped;
+import javax.ws.rs.Consumes;
+import javax.ws.rs.GET;
+import javax.ws.rs.Path;
+import javax.ws.rs.Produces;
+import javax.ws.rs.core.MediaType;
+
+@Path("/weather")
+@Produces(MediaType.APPLICATION_JSON)
+@Consumes(MediaType.APPLICATION_JSON)
+@ApplicationScoped
+public class WeatherService {
+
+    @Path("/day/temperature")
+    @Gauge(name = "weather_day_temperature", absolute = true, unit = "celsius",
+            displayName = "Weather Day Temperature",
+            description = "This metric shows the day temperature.",
+            tags = {"weather=temperature"})
+    @GET
+    @Produces(MediaType.TEXT_PLAIN)
+    public Integer dayTemperature() {
+        return 30;
+    }
+}

examples/mp-metrics-gauge/src/test/java/org/superbiz/rest/WeatherServiceTest.java

@@ -0,0 +1,139 @@
+package org.superbiz.rest; /**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ * <p/>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p/>
+ * 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.
+ */
+
+import org.jboss.arquillian.container.test.api.Deployment;
+import org.jboss.arquillian.junit.Arquillian;
+import org.jboss.arquillian.test.api.ArquillianResource;
+import org.jboss.shrinkwrap.api.ShrinkWrap;
+import org.jboss.shrinkwrap.api.asset.StringAsset;
+import org.jboss.shrinkwrap.api.spec.WebArchive;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import javax.json.Json;
+import javax.json.JsonObject;
+import javax.ws.rs.client.Client;
+import javax.ws.rs.client.ClientBuilder;
+import javax.ws.rs.client.WebTarget;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+import java.io.StringReader;
+import java.net.URL;
+import java.util.stream.Stream;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
+@RunWith(Arquillian.class)
+public class WeatherServiceTest {
+
+    @Deployment(testable = false)
+    public static WebArchive createDeployment() {
+        final WebArchive webArchive = ShrinkWrap.create(WebArchive.class, "test.war")
+                .addClass(WeatherService.class)
+                .addAsWebInfResource(new StringAsset("<beans/>"), "beans.xml");
+        return webArchive;
+    }
+
+    @ArquillianResource
+    private URL base;
+
+    private Client client;
+
+    @Before
+    public void before() {
+        this.client = ClientBuilder.newClient();
+    }
+
+    @After
+    public void after() {
+        this.client.close();
+    }
+
+    @Test
+    public void testGaugeMetric() {
+        WebTarget webTarget = this.client.target(this.base.toExternalForm());
+        final Integer temperature = webTarget
+                .path("/weather/day/temperature")
+                .request()
+                .get(Integer.class);
+        assertEquals(Integer.valueOf(30), temperature);
+
+        final String metricPath = "/metrics/application/weather_day_temperature";
+        assertPrometheusFormat(metricPath);
+        assertJsonFormat(metricPath);
+    }
+
+    private void assertPrometheusFormat(final String metricPath) {
+        WebTarget webTarget = this.client.target(this.base.toExternalForm());
+        final String metric = webTarget
+                .path(metricPath)
+                .request()
+                .accept(MediaType.TEXT_PLAIN)
+                .get(String.class);
+        assertEquals("# TYPE application:weather_day_temperature_celsius gauge\napplication:weather_day_temperature_celsius{weather=\"temperature\"} 30.0\n", metric);
+    }
+
+    private void assertJsonFormat(final String metricPath) {
+        WebTarget webTarget = this.client.target(this.base.toExternalForm());
+        final String metric = webTarget
+                .path(metricPath)
+                .request()
+                .accept(MediaType.APPLICATION_JSON)
+                .get(String.class);
+
+        assertNotNull(metric);
+
+        JsonObject metricJson = Json.createReader(new StringReader(metric)).readObject();
+        JsonObject weatherDayTemperature = metricJson.getJsonObject("weather_day_temperature");
+        assertNotNull(weatherDayTemperature);
+        assertEquals(weatherDayTemperature.getInt("value"), 30);
+    }
+
+    @Test
+    public void testGaugeMetricMetadata() {
+        WebTarget webTarget = this.client.target(this.base.toExternalForm());
+        final Response response = webTarget
+                .path("/metrics/application/weather_day_temperature")
+                .request()
+                .accept(MediaType.APPLICATION_JSON)
+                .options();
+
+        final String metaData = response.readEntity(String.class);
+        JsonObject metadataJson = Json.createReader(new StringReader(metaData)).readObject();
+
+        String[] expectedKeys = {
+                "description",
+                "displayName",
+                "name",
+                "reusable",
+                "tags",
+                "type",
+                "typeRaw",
+                "unit"
+        };
+
+        Stream.of(expectedKeys)
+                .forEach(text ->
+                        assertTrue(
+                                "Expected: " + text + " to be present in " + metaData,
+                                metadataJson.getJsonObject("weather_day_temperature").get(text) != null));
+    }
+}