Cdnc 1692 emit version (#745)

* emitting java client version that is used for a specific domain.

Author: mindaugasbarcauskas

src/main/java/com/uber/cadence/internal/metrics/ClientVersionEmitter.java

@@ -0,0 +1,64 @@
+/*
+ *  Copyright 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"). You may not
+ *  use this file except in compliance with the License. A copy of the License is
+ *  located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ *  or in the "license" file accompanying this file. This file 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 com.uber.cadence.internal.metrics;
+
+import com.uber.cadence.internal.Version;
+import com.uber.m3.tally.Scope;
+import com.uber.m3.util.ImmutableMap;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Map;
+import java.util.Properties;
+
+public class ClientVersionEmitter implements Runnable {
+
+  private Scope metricScope;
+
+  public ClientVersionEmitter(Scope metricScope, String domain) {
+    if (domain == null) {
+      domain = "UNKNOWN";
+    }
+
+    Properties prop = new Properties();
+    InputStream in = Version.class.getResourceAsStream("/com/uber/cadence/version.properties");
+    String version = "";
+    try {
+      prop.load(in);
+      version = prop.getProperty("cadence-client-version");
+    } catch (IOException exception) {
+      version = "UNKNOWN";
+    }
+
+    Map<String, String> tags =
+        new ImmutableMap.Builder<String, String>(2)
+            .put(MetricsTag.VERSION, version)
+            .put(MetricsTag.DOMAIN, domain)
+            .build();
+
+    if (metricScope == null) {
+      this.metricScope = NoopScope.getInstance();
+    } else {
+      this.metricScope = metricScope.tagged(tags);
+    }
+  }
+
+  @Override
+  public void run() {
+    metricScope.counter(MetricsType.JAVA_CLIENT_VERSION).inc(1);
+  }
+}

src/main/java/com/uber/cadence/internal/metrics/MetricsTag.java

@@ -33,4 +33,5 @@ public class MetricsTag {
   public static final String SIDE_EFFECT_ID = "SideEffectID";
   public static final String CHILD_WORKFLOW_ID = "ChildWorkflowID";
   public static final String REQUEST_TYPE = "RequestType";
+  public static final String VERSION = "Version";
 }

src/main/java/com/uber/cadence/internal/metrics/MetricsType.java

@@ -170,4 +170,6 @@ public class MetricsType {
   public static final String REPLAY_SKIPPED_COUNTER = CADENCE_METRICS_PREFIX + "replay-skipped";
   public static final String REPLAY_SUCCESS_COUNTER = CADENCE_METRICS_PREFIX + "replay-succeed";
   public static final String REPLAY_LATENCY = CADENCE_METRICS_PREFIX + "replay-latency";
+
+  public static final String JAVA_CLIENT_VERSION = CADENCE_METRICS_PREFIX + "java-client-version";
 }

src/main/java/com/uber/cadence/internal/sync/WorkflowClientInternal.java

@@ -31,6 +31,7 @@
 import com.uber.cadence.internal.external.GenericWorkflowClientExternalImpl;
 import com.uber.cadence.internal.external.ManualActivityCompletionClientFactory;
 import com.uber.cadence.internal.external.ManualActivityCompletionClientFactoryImpl;
+import com.uber.cadence.internal.metrics.ClientVersionEmitter;
 import com.uber.cadence.internal.sync.WorkflowInvocationHandler.InvocationType;
 import com.uber.cadence.serviceclient.IWorkflowService;
 import com.uber.cadence.workflow.Functions;
@@ -43,6 +44,9 @@
 import java.util.Objects;
 import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+
 import org.apache.thrift.TException;
 
 public final class WorkflowClientInternal implements WorkflowClient {
@@ -52,6 +56,7 @@ public final class WorkflowClientInternal implements WorkflowClient {
   private final WorkflowClientInterceptor[] interceptors;
   private final IWorkflowService workflowService;
   private final WorkflowClientOptions clientOptions;
+  private static boolean emittingClientVersion = false;
 
   /**
    * Creates client that connects to an instance of the Cadence Service.
@@ -64,6 +69,8 @@ public static WorkflowClient newInstance(
       IWorkflowService service, WorkflowClientOptions options) {
     Objects.requireNonNull(service);
     Objects.requireNonNull(options);
+
+    emitClientVersion(options);
     return new WorkflowClientInternal(service, options);
   }
 
@@ -400,4 +407,18 @@ public static <A1, A2, A3, A4, A5, A6, R> CompletableFuture<R> execute(
       A6 arg6) {
     return execute(() -> workflow.apply(arg1, arg2, arg3, arg4, arg5, arg6));
   }
+
+  private synchronized static void emitClientVersion(WorkflowClientOptions options) {
+    if (emittingClientVersion) {
+      return;
+    }
+
+    emittingClientVersion = true;
+    Executors.newSingleThreadScheduledExecutor()
+        .scheduleAtFixedRate(
+            new ClientVersionEmitter(options.getMetricsScope(), options.getDomain()),
+            30,
+            60,
+            TimeUnit.SECONDS);
+  }
 }