Provide metrics of k8s API execution (#15207)

* Provide metrics of k8s API execution
Signed-off-by: Sergii Kabashniuk <skabashniuk@redhat.com>

assembly/assembly-wsmaster-war/src/main/java/org/eclipse/che/api/deploy/WsMasterModule.java

@@ -261,6 +261,8 @@ public class WsMasterModule extends AbstractModule {
     if (Boolean.valueOf(System.getenv("CHE_METRICS_ENABLED"))) {
       install(new org.eclipse.che.core.metrics.MetricsModule());
       install(new WsMasterMetricsModule());
+    } else {
+      install(new org.eclipse.che.core.metrics.NoopMetricsModule());
     }
     if (Boolean.valueOf(System.getenv("CHE_TRACING_ENABLED"))
         && Boolean.valueOf(System.getenv("CHE_METRICS_ENABLED"))) {

core/che-core-metrics-core/pom.xml

@@ -34,6 +34,10 @@
             <groupId>com.google.inject.extensions</groupId>
             <artifactId>guice-servlet</artifactId>
         </dependency>
+        <dependency>
+            <groupId>com.squareup.okhttp3</groupId>
+            <artifactId>okhttp</artifactId>
+        </dependency>
         <dependency>
             <groupId>io.github.mweirauch</groupId>
             <artifactId>micrometer-jvm-extras</artifactId>

core/che-core-metrics-core/src/main/java/org/eclipse/che/core/metrics/MetricsModule.java

@@ -28,6 +28,7 @@ import io.micrometer.core.instrument.binder.system.ProcessorMetrics;
 import io.micrometer.core.instrument.binder.system.UptimeMetrics;
 import io.micrometer.prometheus.PrometheusMeterRegistry;
 import io.prometheus.client.CollectorRegistry;
+import okhttp3.EventListener;
 
 @Beta
 public class MetricsModule extends AbstractModule {
@@ -55,5 +56,7 @@ public class MetricsModule extends AbstractModule {
     meterMultibinder.addBinding().to(ApiResponseCounter.class);
     meterMultibinder.addBinding().to(ProcessMemoryMetrics.class);
     meterMultibinder.addBinding().to(ProcessThreadMetrics.class);
+
+    bind(EventListener.class).toProvider(OkHttpMetricsEventListenerProvider.class);
   }
 }

core/che-core-metrics-core/src/main/java/org/eclipse/che/core/metrics/NoopMetricsModule.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2012-2018 Red Hat, Inc.
+ * This program and the accompanying materials are made
+ * available under the terms of the Eclipse Public License 2.0
+ * which is available at https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *   Red Hat, Inc. - initial API and implementation
+ */
+package org.eclipse.che.core.metrics;
+
+import com.google.inject.AbstractModule;
+import okhttp3.EventListener;
+
+/** Provides dummy implementations of some classes in case if monitoring is turned off. */
+public class NoopMetricsModule extends AbstractModule {
+  @Override
+  protected void configure() {
+    bind(EventListener.class).toInstance(EventListener.NONE);
+  }
+}

core/che-core-metrics-core/src/main/java/org/eclipse/che/core/metrics/OkHttpMetricsEventListenerProvider.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2012-2018 Red Hat, Inc.
+ * This program and the accompanying materials are made
+ * available under the terms of the Eclipse Public License 2.0
+ * which is available at https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *   Red Hat, Inc. - initial API and implementation
+ */
+package org.eclipse.che.core.metrics;
+
+import io.micrometer.core.instrument.MeterRegistry;
+import io.micrometer.core.instrument.binder.okhttp3.OkHttpMetricsEventListener;
+import javax.inject.Inject;
+import javax.inject.Provider;
+import javax.inject.Singleton;
+import okhttp3.OkHttpClient;
+
+/**
+ * Provider of {@link OkHttpMetricsEventListener} class instances that collect metrics from {@link
+ * OkHttpClient}.
+ */
+@Singleton
+public class OkHttpMetricsEventListenerProvider implements Provider<OkHttpMetricsEventListener> {
+
+  private final OkHttpMetricsEventListener listener;
+
+  @Inject
+  public OkHttpMetricsEventListenerProvider(MeterRegistry registry) {
+    this.listener = OkHttpMetricsEventListener.builder(registry, "okhttp.requests").build();
+  }
+
+  @Override
+  public OkHttpMetricsEventListener get() {
+    return listener;
+  }
+}

infrastructures/kubernetes/src/main/java/org/eclipse/che/workspace/infrastructure/kubernetes/KubernetesClientFactory.java

@@ -30,6 +30,7 @@ import okhttp3.Authenticator;
 import okhttp3.ConnectionPool;
 import okhttp3.Credentials;
 import okhttp3.Dispatcher;
+import okhttp3.EventListener;
 import okhttp3.Interceptor;
 import okhttp3.OkHttpClient;
 import okhttp3.Request;
@@ -61,7 +62,8 @@ public class KubernetesClientFactory {
           int maxConcurrentRequestsPerHost,
       @Named("che.infra.kubernetes.client.http.connection_pool.max_idle") int maxIdleConnections,
       @Named("che.infra.kubernetes.client.http.connection_pool.keep_alive_min")
-          int connectionPoolKeepAlive) {
+          int connectionPoolKeepAlive,
+      EventListener eventListener) {
     this.defaultConfig = buildDefaultConfig(masterUrl, doTrustCerts);
     OkHttpClient temporary = HttpClientUtils.createHttpClient(defaultConfig);
     OkHttpClient.Builder builder = temporary.newBuilder();
@@ -69,7 +71,7 @@ public class KubernetesClientFactory {
     builder.connectionPool(
         new ConnectionPool(maxIdleConnections, connectionPoolKeepAlive, TimeUnit.MINUTES));
     oldPool.evictAll();
-    this.httpClient = builder.build();
+    this.httpClient = builder.eventListener(eventListener).build();
     httpClient.dispatcher().setMaxRequests(maxConcurrentRequests);
     httpClient.dispatcher().setMaxRequestsPerHost(maxConcurrentRequestsPerHost);
   }

infrastructures/openshift/src/main/java/org/eclipse/che/workspace/infrastructure/openshift/OpenShiftClientFactory.java

@@ -31,6 +31,7 @@ import javax.inject.Named;
 import javax.inject.Singleton;
 import okhttp3.Authenticator;
 import okhttp3.Credentials;
+import okhttp3.EventListener;
 import okhttp3.Interceptor;
 import okhttp3.OkHttpClient;
 import okhttp3.Request;
@@ -66,14 +67,16 @@ public class OpenShiftClientFactory extends KubernetesClientFactory {
           int maxConcurrentRequestsPerHost,
       @Named("che.infra.kubernetes.client.http.connection_pool.max_idle") int maxIdleConnections,
       @Named("che.infra.kubernetes.client.http.connection_pool.keep_alive_min")
-          int connectionPoolKeepAlive) {
+          int connectionPoolKeepAlive,
+      EventListener eventListener) {
     super(
         masterUrl,
         doTrustCerts,
         maxConcurrentRequests,
         maxConcurrentRequestsPerHost,
         maxIdleConnections,
-        connectionPoolKeepAlive);
+        connectionPoolKeepAlive,
+        eventListener);
     this.configBuilder = configBuilder;
   }