Monitoring API - write framework adapters

Change-Id: Iaba9c4ef6022d01c1f572055316700a3a4dfa8f2
Issue-ID: DCAEGEN2-1589
Signed-off-by: Piotr Jaszczyk <piotr.jaszczyk@nokia.com>

5 files changed, 325 insertions, 0 deletions

diff --git a/standardization/moher-api/server-adapters/spring-webflux/pom.xml b/standardization/moher-api/server-adapters/spring-webflux/pom.xml
new file mode 100644
index 00000000..7eff97aa
--- /dev/null
+++ b/standardization/moher-api/server-adapters/spring-webflux/pom.xml
@@ -0,0 +1,81 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ ============LICENSE_START=======================================================
+  ~ DCAEGEN2-SERVICES-SDK
+  ~ ================================================================================
+  ~ Copyright (C) 2019 Nokia
+  ~ ================================================================================
+  ~ 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.
+  ~ ============LICENSE_END=========================================================
+  -->
+<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">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <artifactId>dcaegen2-sdk-moher-server-adapters</artifactId>
+        <groupId>org.onap.dcaegen2.services.sdk</groupId>
+        <version>1.2.0-SNAPSHOT</version>
+    </parent>
+
+    <name>Monitoring and Healthcheck :: Server Adapters :: Spring Webflux</name>
+    <description>MoHeR Spring server adapter</description>
+    <artifactId>dcae-sdk-moher-spring-webflux</artifactId>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-failsafe-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-webflux</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.onap.dcaegen2.services.sdk</groupId>
+            <artifactId>dcaegen2-sdk-moher-metrics</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.onap.dcaegen2.services.sdk</groupId>
+            <artifactId>dcaegen2-sdk-moher-healthstate</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>hamcrest-core</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-test</artifactId>
+        </dependency>
+        <dependency>
+            <artifactId>spring-boot-starter-webflux</artifactId>
+            <groupId>org.springframework.boot</groupId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+</project>
\ No newline at end of file
diff --git a/standardization/moher-api/server-adapters/spring-webflux/src/main/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/HealthController.java b/standardization/moher-api/server-adapters/spring-webflux/src/main/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/HealthController.java
new file mode 100644
index 00000000..1f9eb4b0
--- /dev/null
+++ b/standardization/moher-api/server-adapters/spring-webflux/src/main/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/HealthController.java
@@ -0,0 +1,72 @@
+/*
+ * ============LICENSE_START====================================
+ * DCAEGEN2-SERVICES-SDK
+ * =========================================================
+ * Copyright (C) 2019 Nokia. All rights reserved.
+ * =========================================================
+ * 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.
+ * ============LICENSE_END=====================================
+ */
+
+package org.onap.dcaegen2.services.sdk.standardization.moher.adapters.springwebflux;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import org.onap.dcaegen2.services.sdk.standardization.moher.health.api.AliveMessage;
+import org.onap.dcaegen2.services.sdk.standardization.moher.health.api.GsonAdaptersHealth;
+import org.onap.dcaegen2.services.sdk.standardization.moher.health.api.Health;
+import org.onap.dcaegen2.services.sdk.standardization.moher.health.api.HealthProvider;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Mono;
+
+@RestController
+@RequestMapping(value = "/health", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
+public class HealthController {
+    private final Gson gson;
+    private final HealthProvider healthProvider;
+
+    public static HealthController create(HealthProvider healthProvider) {
+        GsonBuilder gson = new GsonBuilder();
+        gson.registerTypeAdapterFactory(new GsonAdaptersHealth());
+        return new HealthController(gson.create(), healthProvider);
+    }
+
+    public HealthController(Gson gson, HealthProvider healthProvider) {
+        this.gson = gson;
+        this.healthProvider = healthProvider;
+    }
+
+    @GetMapping("/ready")
+    public Mono<ResponseEntity<String>> readinessCheck() {
+        return healthProvider.currentHealth()
+                .map(health -> responseStatusForHealth(health)
+                        .contentType(MediaType.APPLICATION_JSON_UTF8)
+                        .body(gson.toJson(health)));
+    }
+
+    @GetMapping("/alive")
+    public Mono<String> livenessCheck() {
+        return Mono.just(AliveMessage.ALIVE_MESSAGE_JSON);
+    }
+
+    private ResponseEntity.BodyBuilder responseStatusForHealth(Health health) {
+        return health.healthy()
+                ? ResponseEntity.ok()
+                : ResponseEntity.status(HttpStatus.SERVICE_UNAVAILABLE);
+    }
+}
diff --git a/standardization/moher-api/server-adapters/spring-webflux/src/main/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/MetricsController.java b/standardization/moher-api/server-adapters/spring-webflux/src/main/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/MetricsController.java
new file mode 100644
index 00000000..4ce4fd12
--- /dev/null
+++ b/standardization/moher-api/server-adapters/spring-webflux/src/main/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/MetricsController.java
@@ -0,0 +1,43 @@
+/*
+ * ============LICENSE_START====================================
+ * DCAEGEN2-SERVICES-SDK
+ * =========================================================
+ * Copyright (C) 2019 Nokia. All rights reserved.
+ * =========================================================
+ * 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.
+ * ============LICENSE_END=====================================
+ */
+
+package org.onap.dcaegen2.services.sdk.standardization.moher.adapters.springwebflux;
+
+import org.onap.dcaegen2.services.sdk.standardization.moher.metrics.api.Metrics;
+import org.springframework.http.MediaType;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Mono;
+
+@RestController
+@RequestMapping(value = "/metrics", produces = MediaType.TEXT_PLAIN_VALUE)
+public class MetricsController {
+    private final Metrics metrics;
+
+    public MetricsController(Metrics metrics) {
+        this.metrics = metrics;
+    }
+
+    @GetMapping
+    public Mono<String> prometheusMetrics() {
+        return metrics.collect();
+    }
+}
diff --git a/standardization/moher-api/server-adapters/spring-webflux/src/test/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/HealthControllerIT.java b/standardization/moher-api/server-adapters/spring-webflux/src/test/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/HealthControllerIT.java
new file mode 100644
index 00000000..236cc16f
--- /dev/null
+++ b/standardization/moher-api/server-adapters/spring-webflux/src/test/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/HealthControllerIT.java
@@ -0,0 +1,81 @@
+/*
+ * ============LICENSE_START====================================
+ * DCAEGEN2-SERVICES-SDK
+ * =========================================================
+ * Copyright (C) 2019 Nokia. All rights reserved.
+ * =========================================================
+ * 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.
+ * ============LICENSE_END=====================================
+ */
+
+package org.onap.dcaegen2.services.sdk.standardization.moher.adapters.springwebflux;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.concurrent.atomic.AtomicReference;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+
+import org.junit.jupiter.api.Test;
+import org.onap.dcaegen2.services.sdk.standardization.moher.health.api.AliveMessage;
+import org.onap.dcaegen2.services.sdk.standardization.moher.health.api.GsonAdaptersHealth;
+import org.onap.dcaegen2.services.sdk.standardization.moher.health.api.Health;
+import org.onap.dcaegen2.services.sdk.standardization.moher.health.api.HealthProvider;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.reactive.server.WebTestClient;
+
+import reactor.core.publisher.Mono;
+
+class HealthControllerIT {
+
+    private final AtomicReference<Health> currentHealth = new AtomicReference<>();
+    private final HealthProvider healthProvider = () -> Mono.fromCallable(currentHealth::get);
+    private final HealthController sut = HealthController.create(healthProvider);
+    private final WebTestClient client = WebTestClient.bindToController(sut).build();
+    private final Gson gsonForDeserialization = new GsonBuilder().registerTypeAdapterFactory(new GsonAdaptersHealth())
+            .create();
+
+    @Test
+    void readinessProbeShouldReturnOkWhenHealthy() {
+        final Health expectedHealth = Health.createHealthy("Ready to go");
+        currentHealth.set(expectedHealth);
+
+        client.get().uri("/health/ready").accept(MediaType.APPLICATION_JSON).exchange().expectStatus().isOk()
+                .expectBody(String.class).value(body -> {
+                    final Health actualHealth = gsonForDeserialization.fromJson(body, Health.class);
+                    assertThat(actualHealth).isEqualTo(expectedHealth);
+                });
+    }
+
+    @Test
+    void readinessProbeShouldReturnUnavailableWhenNotHealthy() {
+        final Health expectedHealth = Health.createUnhealthy("Waiting for CBS update");
+        currentHealth.set(expectedHealth);
+
+        client.get().uri("/health/ready").accept(MediaType.APPLICATION_JSON).exchange().expectStatus()
+                .is5xxServerError().expectBody(String.class).value(body -> {
+                    final Health actualHealth = gsonForDeserialization.fromJson(body, Health.class);
+                    assertThat(actualHealth).isEqualTo(expectedHealth);
+                });
+    }
+
+    @Test
+    void livenessProbeShouldAlwaysReturnOk() {
+        client.get().uri("/health/alive").accept(MediaType.APPLICATION_JSON).exchange().expectStatus().isOk()
+                .expectBody(String.class).value(body -> {
+                    assertThat(body).isEqualTo(AliveMessage.ALIVE_MESSAGE_JSON);
+                });
+    }
+
+}
diff --git a/standardization/moher-api/server-adapters/spring-webflux/src/test/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/MetricsControllerIT.java b/standardization/moher-api/server-adapters/spring-webflux/src/test/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/MetricsControllerIT.java
new file mode 100644
index 00000000..32d00449
--- /dev/null
+++ b/standardization/moher-api/server-adapters/spring-webflux/src/test/java/org/onap/dcaegen2/services/sdk/standardization/moher/adapters/springwebflux/MetricsControllerIT.java
@@ -0,0 +1,48 @@
+/*
+ * ============LICENSE_START====================================
+ * DCAEGEN2-SERVICES-SDK
+ * =========================================================
+ * Copyright (C) 2019 Nokia. All rights reserved.
+ * =========================================================
+ * 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.
+ * ============LICENSE_END=====================================
+ */
+
+package org.onap.dcaegen2.services.sdk.standardization.moher.adapters.springwebflux;
+
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import io.micrometer.prometheus.PrometheusMeterRegistry;
+import org.junit.jupiter.api.Test;
+import org.onap.dcaegen2.services.sdk.standardization.moher.metrics.api.Metrics;
+import org.onap.dcaegen2.services.sdk.standardization.moher.metrics.api.MetricsFactory;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.reactive.server.WebTestClient;
+
+class MetricsControllerIT {
+
+    private final PrometheusMeterRegistry defaultRegistry = MetricsFactory.createDefaultRegistry();
+    private final Metrics metrics = MetricsFactory.createMetrics(defaultRegistry);
+    private final MetricsController sut = new MetricsController(metrics);
+    private final WebTestClient client = WebTestClient.bindToController(sut).build();
+
+    @Test
+    void prometheusMetrics() {
+        client.get().uri("/metrics").accept(MediaType.ALL).exchange()
+                .expectStatus().isOk()
+                .expectHeader().contentTypeCompatibleWith(MediaType.TEXT_PLAIN)
+                .expectBody(String.class)
+                .value(body -> assertThat(body).contains("system_cpu").contains("jvm_classes"));
+    }
+}