Merge remote-tracking branch 'origin/qualified-spring-mvc-endpoints' into...

Merge remote-tracking branch 'origin/qualified-spring-mvc-endpoints' into qualified-spring-mvc-endpoints

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/boot/AgentPackagePath.java

@@ -19,6 +19,7 @@
 
 package org.apache.skywalking.apm.agent.core.boot;
 
+import java.net.URISyntaxException;
 import org.apache.skywalking.apm.agent.core.logging.api.ILog;
 import org.apache.skywalking.apm.agent.core.logging.api.LogManager;
 
@@ -61,9 +62,11 @@ public class AgentPackagePath {
                 urlString = urlString.substring(urlString.indexOf("file:"), insidePathIndex);
                 File agentJarFile = null;
                 try {
-                    agentJarFile = new File(new URL(urlString).getFile());
+                    agentJarFile = new File(new URL(urlString).toURI());
                 } catch (MalformedURLException e) {
                     logger.error(e, "Can not locate agent jar file by url:" + urlString);
+                } catch (URISyntaxException e) {
+                    logger.error(e, "Can not locate agent jar file by url:" + urlString);
                 }
                 if (agentJarFile.exists()) {
                     return agentJarFile.getParentFile();

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/context/AbstractTracerContext.java

@@ -16,7 +16,6 @@
  *
  */
 
-
 package org.apache.skywalking.apm.agent.core.context;
 
 import org.apache.skywalking.apm.agent.core.context.trace.AbstractSpan;
@@ -28,41 +27,38 @@ import org.apache.skywalking.apm.agent.core.context.trace.AbstractSpan;
  */
 public interface AbstractTracerContext {
     /**
-     * Prepare for the cross-process propagation.
-     * How to initialize the carrier, depends on the implementation.
+     * Prepare for the cross-process propagation. How to initialize the carrier, depends on the implementation.
      *
      * @param carrier to carry the context for crossing process.
      */
     void inject(ContextCarrier carrier);
 
     /**
-     * Build the reference between this segment and a cross-process segment.
-     * How to build, depends on the implementation.
+     * Build the reference between this segment and a cross-process segment. How to build, depends on the
+     * implementation.
      *
      * @param carrier carried the context from a cross-process segment.
      */
     void extract(ContextCarrier carrier);
 
     /**
-     * Capture a snapshot for cross-thread propagation.
-     * It's a similar concept with ActiveSpan.Continuation in OpenTracing-java
-     * How to build, depends on the implementation.
+     * Capture a snapshot for cross-thread propagation. It's a similar concept with ActiveSpan.Continuation in
+     * OpenTracing-java How to build, depends on the implementation.
      *
      * @return the {@link ContextSnapshot} , which includes the reference context.
      */
     ContextSnapshot capture();
 
     /**
-     * Build the reference between this segment and a cross-thread segment.
-     * How to build, depends on the implementation.
+     * Build the reference between this segment and a cross-thread segment. How to build, depends on the
+     * implementation.
      *
      * @param snapshot from {@link #capture()} in the parent thread.
      */
     void continued(ContextSnapshot snapshot);
 
     /**
-     * Get the global trace id, if needEnhance.
-     * How to build, depends on the implementation.
+     * Get the global trace id, if needEnhance. How to build, depends on the implementation.
      *
      * @return the string represents the id.
      */
@@ -102,7 +98,21 @@ public interface AbstractTracerContext {
      * Finish the given span, and the given span should be the active span of current tracing context(stack)
      *
      * @param span to finish
+     * @return true when context should be clear.
+     */
+    boolean stopSpan(AbstractSpan span);
+
+    /**
+     * Notify this context, current span is going to be finished async in another thread.
+     *
+     * @return The current context
      */
-    void stopSpan(AbstractSpan span);
+    AbstractTracerContext awaitFinishAsync();
 
+    /**
+     * The given span could be stopped officially.
+     *
+     * @param span to be stopped.
+     */
+    void asyncStop(AsyncSpan span);
 }

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/context/AsyncSpan.java

+/*
+ * 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
+ *
+ *     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.
+ *
+ */
+
+package org.apache.skywalking.apm.agent.core.context;
+
+import org.apache.skywalking.apm.agent.core.context.trace.AbstractSpan;
+
+/**
+ * Span could use these APIs to active and extend its lift cycle across thread.
+ *
+ * This is typical used in async plugin, especially RPC plugins.
+ *
+ * @author wusheng
+ */
+public interface AsyncSpan {
+    /**
+     * The span finish at current tracing context, but the current span is still alive, until {@link #asyncFinish}
+     * called.
+     *
+     * This method must be called
+     *
+     * 1. In original thread(tracing context).
+     * 2. Current span is active span.
+     *
+     * During alive, tags, logs and attributes of the span could be changed, in any thread.
+     *
+     * The execution times of {@link #prepareForAsync} and {@link #asyncFinish()} must match.
+     *
+     * @return the current span
+     */
+    AbstractSpan prepareForAsync();
+
+    /**
+     * Notify the span, it could be finished.
+     *
+     * The execution times of {@link #prepareForAsync} and {@link #asyncFinish()} must match.
+     *
+     * @return the current span
+     */
+    AbstractSpan asyncFinish();
+}

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/context/ContextManager.java

@@ -18,14 +18,11 @@
 
 package org.apache.skywalking.apm.agent.core.context;
 
-import org.apache.skywalking.apm.agent.core.boot.BootService;
-import org.apache.skywalking.apm.agent.core.boot.ServiceManager;
+import org.apache.skywalking.apm.agent.core.boot.*;
 import org.apache.skywalking.apm.agent.core.conf.RemoteDownstreamConfig;
-import org.apache.skywalking.apm.agent.core.context.trace.AbstractSpan;
-import org.apache.skywalking.apm.agent.core.context.trace.TraceSegment;
+import org.apache.skywalking.apm.agent.core.context.trace.*;
 import org.apache.skywalking.apm.agent.core.dictionary.DictionaryUtil;
-import org.apache.skywalking.apm.agent.core.logging.api.ILog;
-import org.apache.skywalking.apm.agent.core.logging.api.LogManager;
+import org.apache.skywalking.apm.agent.core.logging.api.*;
 import org.apache.skywalking.apm.agent.core.sampling.SamplingService;
 import org.apache.skywalking.apm.util.StringUtil;
 
@@ -39,7 +36,7 @@ import org.apache.skywalking.apm.util.StringUtil;
  *
  * @author wusheng
  */
-public class ContextManager implements TracingContextListener, BootService, IgnoreTracerContextListener {
+public class ContextManager implements BootService {
     private static final ILog logger = LogManager.getLogger(ContextManager.class);
     private static ThreadLocal<AbstractTracerContext> CONTEXT = new ThreadLocal<AbstractTracerContext>();
     private static ThreadLocal<RuntimeContext> RUNTIME_CONTEXT = new ThreadLocal<RuntimeContext>();
@@ -59,7 +56,7 @@ public class ContextManager implements TracingContextListener, BootService, Igno
             } else {
                 if (RemoteDownstreamConfig.Agent.SERVICE_ID != DictionaryUtil.nullValue()
                     && RemoteDownstreamConfig.Agent.SERVICE_INSTANCE_ID != DictionaryUtil.nullValue()
-                    ) {
+                ) {
                     context = EXTEND_SERVICE.createTraceContext(operationName, forceSampling);
                 } else {
                     /**
@@ -152,6 +149,14 @@ public class ContextManager implements TracingContextListener, BootService, Igno
         }
     }
 
+    public static AbstractTracerContext awaitFinishAsync(AbstractSpan span) {
+        AbstractSpan activeSpan = activeSpan();
+        if (span != activeSpan) {
+            throw new RuntimeException("Span is not the active in current context.");
+        }
+        return get().awaitFinishAsync();
+    }
+
     public static AbstractSpan activeSpan() {
         return get().activeSpan();
     }
@@ -161,7 +166,9 @@ public class ContextManager implements TracingContextListener, BootService, Igno
     }
 
     public static void stopSpan(AbstractSpan span) {
-        get().stopSpan(span);
+        if (get().stopSpan(span)) {
+            CONTEXT.remove();
+        }
     }
 
     @Override
@@ -171,8 +178,6 @@ public class ContextManager implements TracingContextListener, BootService, Igno
 
     @Override
     public void boot() {
-        ContextManagerExtendService service = ServiceManager.INSTANCE.findService(ContextManagerExtendService.class);
-        service.registerListeners(this);
     }
 
     @Override
@@ -184,16 +189,6 @@ public class ContextManager implements TracingContextListener, BootService, Igno
 
     }
 
-    @Override
-    public void afterFinished(TraceSegment traceSegment) {
-        CONTEXT.remove();
-    }
-
-    @Override
-    public void afterFinished(IgnoredTracerContext traceSegment) {
-        CONTEXT.remove();
-    }
-
     public static boolean isActive() {
         return get() != null;
     }

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/context/ContextManagerExtendService.java

@@ -18,9 +18,7 @@
 
 package org.apache.skywalking.apm.agent.core.context;
 
-import org.apache.skywalking.apm.agent.core.boot.BootService;
-import org.apache.skywalking.apm.agent.core.boot.DefaultImplementor;
-import org.apache.skywalking.apm.agent.core.boot.ServiceManager;
+import org.apache.skywalking.apm.agent.core.boot.*;
 import org.apache.skywalking.apm.agent.core.conf.Config;
 import org.apache.skywalking.apm.agent.core.sampling.SamplingService;
 
@@ -45,11 +43,6 @@ public class ContextManagerExtendService implements BootService {
 
     }
 
-    public void registerListeners(ContextManager manager) {
-        TracingContext.ListenerManager.add(manager);
-        IgnoredTracerContext.ListenerManager.add(manager);
-    }
-
     public AbstractTracerContext createTraceContext(String operationName, boolean forceSampling) {
         AbstractTracerContext context;
         int suffixIdx = operationName.lastIndexOf(".");

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/context/IgnoredTracerContext.java

@@ -16,17 +16,14 @@
  *
  */
 
-
 package org.apache.skywalking.apm.agent.core.context;
 
-import java.util.LinkedList;
-import java.util.List;
-import org.apache.skywalking.apm.agent.core.context.trace.AbstractSpan;
-import org.apache.skywalking.apm.agent.core.context.trace.NoopSpan;
+import java.util.*;
+import org.apache.skywalking.apm.agent.core.context.trace.*;
 
 /**
- * The <code>IgnoredTracerContext</code> represent a context should be ignored.
- * So it just maintains the stack with an integer depth field.
+ * The <code>IgnoredTracerContext</code> represent a context should be ignored. So it just maintains the stack with an
+ * integer depth field.
  *
  * All operations through this will be ignored, and keep the memory and gc cost as low as possible.
  *
@@ -88,11 +85,20 @@ public class IgnoredTracerContext implements AbstractTracerContext {
     }
 
     @Override
-    public void stopSpan(AbstractSpan span) {
+    public boolean stopSpan(AbstractSpan span) {
         stackDepth--;
         if (stackDepth == 0) {
             ListenerManager.notifyFinish(this);
         }
+        return stackDepth == 0;
+    }
+
+    @Override public AbstractTracerContext awaitFinishAsync() {
+        return this;
+    }
+
+    @Override public void asyncStop(AsyncSpan span) {
+
     }
 
     public static class ListenerManager {

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/context/TracingContext.java

@@ -18,25 +18,14 @@
 
 package org.apache.skywalking.apm.agent.core.context;
 
-import java.util.LinkedList;
-import java.util.List;
+import java.util.*;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.locks.ReentrantLock;
 import org.apache.skywalking.apm.agent.core.boot.ServiceManager;
 import org.apache.skywalking.apm.agent.core.conf.Config;
-import org.apache.skywalking.apm.agent.core.context.trace.AbstractSpan;
-import org.apache.skywalking.apm.agent.core.context.trace.AbstractTracingSpan;
-import org.apache.skywalking.apm.agent.core.context.trace.EntrySpan;
-import org.apache.skywalking.apm.agent.core.context.trace.ExitSpan;
-import org.apache.skywalking.apm.agent.core.context.trace.LocalSpan;
-import org.apache.skywalking.apm.agent.core.context.trace.NoopExitSpan;
-import org.apache.skywalking.apm.agent.core.context.trace.NoopSpan;
-import org.apache.skywalking.apm.agent.core.context.trace.TraceSegment;
-import org.apache.skywalking.apm.agent.core.context.trace.TraceSegmentRef;
-import org.apache.skywalking.apm.agent.core.context.trace.WithPeerInfo;
-import org.apache.skywalking.apm.agent.core.dictionary.DictionaryManager;
-import org.apache.skywalking.apm.agent.core.dictionary.DictionaryUtil;
-import org.apache.skywalking.apm.agent.core.dictionary.PossibleFound;
-import org.apache.skywalking.apm.agent.core.logging.api.ILog;
-import org.apache.skywalking.apm.agent.core.logging.api.LogManager;
+import org.apache.skywalking.apm.agent.core.context.trace.*;
+import org.apache.skywalking.apm.agent.core.dictionary.*;
+import org.apache.skywalking.apm.agent.core.logging.api.*;
 import org.apache.skywalking.apm.agent.core.sampling.SamplingService;
 import org.apache.skywalking.apm.util.StringUtil;
 
@@ -80,6 +69,13 @@ public class TracingContext implements AbstractTracerContext {
      */
     private int spanIdGenerator;
 
+    /**
+     * The counter indicates
+     */
+    private AtomicInteger asyncSpanCounter;
+    private volatile boolean isRunningInAsyncMode;
+    private ReentrantLock asyncFinishLock;
+
     /**
      * Initialize all fields with default value.
      */
@@ -89,6 +85,9 @@ public class TracingContext implements AbstractTracerContext {
         if (samplingService == null) {
             samplingService = ServiceManager.INSTANCE.findService(SamplingService.class);
         }
+        asyncSpanCounter = new AtomicInteger(0);
+        isRunningInAsyncMode = false;
+        asyncFinishLock = new ReentrantLock();
     }
 
     /**
@@ -392,7 +391,7 @@ public class TracingContext implements AbstractTracerContext {
      * @param span to finish
      */
     @Override
-    public void stopSpan(AbstractSpan span) {
+    public boolean stopSpan(AbstractSpan span) {
         AbstractSpan lastSpan = peek();
         if (lastSpan == span) {
             if (lastSpan instanceof AbstractTracingSpan) {
@@ -407,9 +406,41 @@ public class TracingContext implements AbstractTracerContext {
             throw new IllegalStateException("Stopping the unexpected span = " + span);
         }
 
-        if (activeSpanStack.isEmpty()) {
-            this.finish();
+        if (checkFinishConditions()) {
+            finish();
+        }
+
+        return activeSpanStack.isEmpty();
+    }
+
+    @Override public AbstractTracerContext awaitFinishAsync() {
+        isRunningInAsyncMode = true;
+        asyncSpanCounter.addAndGet(1);
+        return this;
+    }
+
+    @Override public void asyncStop(AsyncSpan span) {
+        asyncSpanCounter.addAndGet(-1);
+
+        if (checkFinishConditions()) {
+            finish();
+        }
+    }
+
+    private boolean checkFinishConditions() {
+        if (isRunningInAsyncMode) {
+            asyncFinishLock.lock();
+        }
+        try {
+            if (activeSpanStack.isEmpty() && asyncSpanCounter.get() == 0) {
+                return true;
+            }
+        } finally {
+            if (isRunningInAsyncMode) {
+                asyncFinishLock.unlock();
+            }
         }
+        return false;
     }
 
     /**

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/context/trace/AbstractSpan.java

@@ -19,6 +19,7 @@
 package org.apache.skywalking.apm.agent.core.context.trace;
 
 import java.util.Map;
+import org.apache.skywalking.apm.agent.core.context.AsyncSpan;
 import org.apache.skywalking.apm.agent.core.context.tag.AbstractTag;
 import org.apache.skywalking.apm.network.trace.component.Component;
 import org.apache.skywalking.apm.network.trace.component.ComponentsDefine;
@@ -28,7 +29,7 @@ import org.apache.skywalking.apm.network.trace.component.ComponentsDefine;
  *
  * @author wusheng
  */
-public interface AbstractSpan {
+public interface AbstractSpan extends AsyncSpan {
     /**
      * Set the component id, which defines in {@link ComponentsDefine}
      *

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/context/trace/AbstractTracingSpan.java

@@ -18,15 +18,10 @@
 
 package org.apache.skywalking.apm.agent.core.context.trace;
 
-import java.util.ArrayList;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Map;
-import org.apache.skywalking.apm.agent.core.context.tag.AbstractTag;
-import org.apache.skywalking.apm.agent.core.context.tag.StringTag;
-import org.apache.skywalking.apm.agent.core.context.util.KeyValuePair;
-import org.apache.skywalking.apm.agent.core.context.util.TagValuePair;
-import org.apache.skywalking.apm.agent.core.context.util.ThrowableTransformer;
+import java.util.*;
+import org.apache.skywalking.apm.agent.core.context.*;
+import org.apache.skywalking.apm.agent.core.context.tag.*;
+import org.apache.skywalking.apm.agent.core.context.util.*;
 import org.apache.skywalking.apm.agent.core.dictionary.DictionaryUtil;
 import org.apache.skywalking.apm.network.language.agent.SpanType;
 import org.apache.skywalking.apm.network.language.agent.v2.SpanObjectV2;
@@ -45,6 +40,9 @@ public abstract class AbstractTracingSpan implements AbstractSpan {
     protected String operationName;
     protected int operationId;
     protected SpanLayer layer;
+    protected boolean isInAsyncMode = false;
+    protected volatile AbstractTracerContext context;
+
     /**
      * The start time of this Span.
      */
@@ -322,4 +320,20 @@ public abstract class AbstractTracingSpan implements AbstractSpan {
             refs.add(ref);
         }
     }
+
+    @Override public AbstractSpan prepareForAsync() {
+        context = ContextManager.awaitFinishAsync(this);
+        isInAsyncMode = true;
+        return this;
+    }
+
+    @Override public AbstractSpan asyncFinish() {
+        if (!isInAsyncMode) {
+            throw new RuntimeException("Span is not in async mode, please use '#prepareForAsync' to active.");
+        }
+
+        this.endTime = System.currentTimeMillis();
+        context.asyncStop(this);
+        return this;
+    }
 }

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/context/trace/NoopSpan.java

@@ -115,4 +115,12 @@ public class NoopSpan implements AbstractSpan {
     @Override public AbstractSpan setPeer(String remotePeer) {
         return this;
     }
+
+    @Override public AbstractSpan prepareForAsync() {
+        return this;
+    }
+
+    @Override public AbstractSpan asyncFinish() {
+        return this;
+    }
 }

apm-sniffer/apm-agent-core/src/test/java/org/apache/skywalking/apm/agent/core/boot/ServiceManagerTest.java

@@ -69,16 +69,13 @@ public class ServiceManagerTest {
 
     private void assertIgnoreTracingContextListener() throws Exception {
         List<TracingContextListener> listeners = getFieldValue(IgnoredTracerContext.ListenerManager.class, "LISTENERS");
-        assertThat(listeners.size(), is(1));
-
-        assertThat(listeners.contains(ServiceManager.INSTANCE.findService(ContextManager.class)), is(true));
+        assertThat(listeners.size(), is(0));
     }
 
     private void assertTracingContextListener() throws Exception {
         List<TracingContextListener> listeners = getFieldValue(TracingContext.ListenerManager.class, "LISTENERS");
-        assertThat(listeners.size(), is(2));
+        assertThat(listeners.size(), is(1));
 
-        assertThat(listeners.contains(ServiceManager.INSTANCE.findService(ContextManager.class)), is(true));
         assertThat(listeners.contains(ServiceManager.INSTANCE.findService(TraceSegmentServiceClient.class)), is(true));
     }
 

docs/en/guides/How-to-build.md

@@ -30,6 +30,7 @@ For each official Apache release, there is a complete and independent source cod
     * `grpc-java` and `java` folders in **apm-protocol/apm-network/target/generated-sources/protobuf**
     * `grpc-java` and `java` folders in **oap-server/server-core/target/generated-sources/protobuf**
     * `grpc-java` and `java` folders in **oap-server/server-receiver-plugin/skywalking-istio-telemetry-receiver-plugin/target/generated-sources/protobuf**
+    * `grpc-java` and `java` folders in **oap-server/server-receiver-plugin/envoy-metrics-receiver-plugin/target/generated-sources/protobuf**
     * `antlr4` folder in **oap-server/generate-tool-grammar/target/generated-sources**
     * `oal` folder in **oap-server/generated-analysis/target/generated-sources**
     

docs/en/guides/Java-Plugin-Development-Guide.md

@@ -160,6 +160,42 @@ SpanLayer is the catalog of span. Here are 5 values:
 Component IDs are defined and reserved by SkyWalking project.
 For component name/ID extension, please follow [cComponent library definition and extension](Component-library-settings.md) document.
 
+### Advanced APIs
+#### Async Span APIs
+There is a set of advanced APIs in Span, which work specific for async scenario. When tags, logs, attributes(including end time) of the span
+needs to set in another thread, you should use these APIs.
+
+```java
+    /**
+     * The span finish at current tracing context, but the current span is still alive, until {@link #asyncFinish}
+     * called.
+     *
+     * This method must be called<br/>
+     * 1. In original thread(tracing context).
+     * 2. Current span is active span.
+     *
+     * During alive, tags, logs and attributes of the span could be changed, in any thread.
+     *
+     * The execution times of {@link #prepareForAsync} and {@link #asyncFinish()} must match.
+     *
+     * @return the current span
+     */
+    AbstractSpan prepareForAsync();
+
+    /**
+     * Notify the span, it could be finished.
+     *
+     * The execution times of {@link #prepareForAsync} and {@link #asyncFinish()} must match.
+     *
+     * @return the current span
+     */
+    AbstractSpan asyncFinish();
+```
+1. Call `#prepareForAsync` in original context.
+1. Propagate the span to any other thread.
+1. After all set, call `#asyncFinish` in any thread.
+1. Tracing context will be finished and report to backend when all spans's `#prepareForAsync` finished(Judged by count of API execution).
+
 ## Develop a plugin
 ### Abstract
 The basic method to trace is intercepting a Java method, by using byte code manipulation tech and AOP concept.

docs/en/protocols/Trace-Data-Protocol-v2.md

@@ -47,9 +47,9 @@ e.g. accessing DB by JDBC, reading Redis/Memcached are cataloged an ExitSpan.
 
 3. Span parent info called Reference, which is included in span. Reference carries more fields besides 
 trace id, parent segment id, span id. Others are **entry service instance id**, **parent service instance id**,
-**entry endpoint**, **parent endpoint** and **network address**. Follow [SkyWalking Trace Data Protocol v2](Trace-Data-Protocol-v2.md),
+**entry endpoint**, **parent endpoint** and **network address**. Follow [Cross Process Propagation Headers Protocol v2](Skywalking-Cross-Process-Propagation-Headers-Protocol-v2.md),
 you will know how to get all these fields.
 
 ### Step 3. Keep alive.
 `ServiceInstancePing#doPing` should be called per several seconds. Make the backend know this instance is still
-alive. Existed **service instance id** and **UUID** used in `doServiceInstanceRegister` are required.
\ No newline at end of file
+alive. Existed **service instance id** and **UUID** used in `doServiceInstanceRegister` are required.

docs/powered-by.md

@@ -48,7 +48,8 @@ or providing commercial products including Apache SkyWalking.
 1. Mxnavi. 沈阳美行科技有限公司 http://www.mxnavi.com/
 1. Moji 墨叽（深圳）科技有限公司 https://www.mojivip.com
 1. Mypharma.com 北京融贯电子商务有限公司 https://www.mypharma.com
-1. Primeton.com 普元信息技术股份有限公司 http://www.primeton.com . 
+1. Osacart in WeChat app 广州美克曼尼电子商务有限公司
+1. Primeton.com 普元信息技术股份有限公司 http://www.primeton.com 
 1. qiniu.com 七牛云 http://qiniu.com 
 1. Qingyidai.com 轻易贷 https://www.qingyidai.com/
 1. Qsdjf.com 浙江钱宝网络科技有限公司 https://www.qsdjf.com/index.html
@@ -92,3 +93,5 @@ Provide a customized version SkyWalking agent. It could provide distributed trac
 ## Primeton
 Integrated in Primeton EOS PLATFORM 8, which is a commercial micro-service platform.
 
+## Oscart
+Use multiple language agents from SkyWalking and its ecosystem, including SkyWalking Javaagent and [SkyAPM nodejs agent](https://github.com/SkyAPM/SkyAPM-nodejs). SkyWalking OAP platform acts as backend and visualization.

oap-server/exporter/pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ 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
+  ~
+  ~     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.
+  ~
+  -->
+
+<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>oap-server</artifactId>
+        <groupId>org.apache.skywalking</groupId>
+        <version>6.1.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>exporter</artifactId>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.skywalking</groupId>
+            <artifactId>server-core</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+    </dependencies>
+</project>
\ No newline at end of file

oap-server/exporter/src/main/resources/META-INF/services/org.apache.skywalking.oap.server.library.module.ModuleProvider

+#
+# 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
+#
+#     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.
+#
+#

oap-server/generate-tool/src/main/resources/code-templates/IndicatorImplementor.ftl

@@ -28,8 +28,6 @@ import org.apache.skywalking.oap.server.core.Const;
         <#break>
     </#if>
 </#list>
-import org.apache.skywalking.oap.server.core.alarm.AlarmMeta;
-import org.apache.skywalking.oap.server.core.alarm.AlarmSupported;
 import org.apache.skywalking.oap.server.core.analysis.indicator.*;
 import org.apache.skywalking.oap.server.core.analysis.indicator.annotation.IndicatorType;
 import org.apache.skywalking.oap.server.core.remote.annotation.StreamData;
@@ -45,7 +43,7 @@ import org.apache.skywalking.oap.server.core.storage.StorageBuilder;
 @IndicatorType
 @StreamData
 @StorageEntity(name = "${tableName}", builder = ${metricName}Indicator.Builder.class, sourceScopeId = ${sourceScopeId})
-public class ${metricName}Indicator extends ${indicatorClassName} implements AlarmSupported {
+public class ${metricName}Indicator extends ${indicatorClassName} implements WithMetadata {
 
 <#list fieldsFromSource as sourceField>
     @Setter @Getter @Column(columnName = "${sourceField.columnName}") <#if sourceField.isID()>@IDColumn</#if> private ${sourceField.typeName} ${sourceField.fieldName};
@@ -170,8 +168,8 @@ public class ${metricName}Indicator extends ${indicatorClassName} implements Ala
 
     }
 
-    @Override public AlarmMeta getAlarmMeta() {
-        return new AlarmMeta("${varName}", ${sourceScopeId}<#if (fieldsFromSource?size>0) ><#list fieldsFromSource as field><#if field.isID()>, ${field.fieldName}</#if></#list></#if>);
+    @Override public IndicatorMetaInfo getMeta() {
+        return new IndicatorMetaInfo("${varName}", ${sourceScopeId}<#if (fieldsFromSource?size>0) ><#list fieldsFromSource as field><#if field.isID()>, ${field.fieldName}</#if></#list></#if>);
     }
 
     @Override

oap-server/generate-tool/src/test/resources/expectedFiles/IndicatorImplementorExpected.java

@@ -21,8 +21,6 @@ package org.apache.skywalking.oap.server.core.analysis.generated.service.service
 import java.util.*;
 import lombok.*;
 import org.apache.skywalking.oap.server.core.Const;
-import org.apache.skywalking.oap.server.core.alarm.AlarmMeta;
-import org.apache.skywalking.oap.server.core.alarm.AlarmSupported;
 import org.apache.skywalking.oap.server.core.analysis.indicator.*;
 import org.apache.skywalking.oap.server.core.analysis.indicator.annotation.IndicatorType;
 import org.apache.skywalking.oap.server.core.remote.annotation.StreamData;
@@ -38,7 +36,7 @@ import org.apache.skywalking.oap.server.core.storage.StorageBuilder;
 @IndicatorType
 @StreamData
 @StorageEntity(name = "service_avg", builder = ServiceAvgIndicator.Builder.class, sourceScopeId = 1)
-public class ServiceAvgIndicator extends LongAvgIndicator implements AlarmSupported {
+public class ServiceAvgIndicator extends LongAvgIndicator implements WithMetadata {
 
     @Setter @Getter @Column(columnName = "entity_id") @IDColumn private java.lang.String entityId;
 
@@ -108,8 +106,8 @@ public class ServiceAvgIndicator extends LongAvgIndicator implements AlarmSuppor
 
     }
 
-    @Override public AlarmMeta getAlarmMeta() {
-        return new AlarmMeta("generate_indicator", 1, entityId);
+    @Override public IndicatorMetaInfo getMeta() {
+        return new IndicatorMetaInfo("generate_indicator", 1, entityId);
     }
 
     @Override

oap-server/pom.xml

@@ -41,6 +41,7 @@
         <module>generate-tool</module>
         <module>server-telemetry</module>
         <module>generate-tool-grammar</module>
+        <module>exporter</module>
     </modules>
 
     <properties>

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/alarm/AlarmEntrance.java

@@ -20,7 +20,7 @@ package org.apache.skywalking.oap.server.core.alarm;
 
 import java.util.concurrent.locks.ReentrantLock;
 import org.apache.skywalking.oap.server.core.CoreModule;
-import org.apache.skywalking.oap.server.core.analysis.indicator.Indicator;
+import org.apache.skywalking.oap.server.core.analysis.indicator.*;
 import org.apache.skywalking.oap.server.core.cache.*;
 import org.apache.skywalking.oap.server.core.register.*;
 import org.apache.skywalking.oap.server.library.module.ModuleManager;
@@ -50,33 +50,33 @@ public class AlarmEntrance {
 
         init();
 
-        AlarmMeta alarmMeta = ((AlarmSupported)indicator).getAlarmMeta();
+        IndicatorMetaInfo indicatorMetaInfo = ((WithMetadata)indicator).getMeta();
 
         MetaInAlarm metaInAlarm;
-        switch (alarmMeta.getScope()) {
+        switch (indicatorMetaInfo.getScope()) {
             case SERVICE:
-                int serviceId = Integer.parseInt(alarmMeta.getId());
+                int serviceId = Integer.parseInt(indicatorMetaInfo.getId());
                 ServiceInventory serviceInventory = serviceInventoryCache.get(serviceId);
                 ServiceMetaInAlarm serviceMetaInAlarm = new ServiceMetaInAlarm();
-                serviceMetaInAlarm.setIndicatorName(alarmMeta.getIndicatorName());
+                serviceMetaInAlarm.setIndicatorName(indicatorMetaInfo.getIndicatorName());
                 serviceMetaInAlarm.setId(serviceId);
                 serviceMetaInAlarm.setName(serviceInventory.getName());
                 metaInAlarm = serviceMetaInAlarm;
                 break;
             case SERVICE_INSTANCE:
-                int serviceInstanceId = Integer.parseInt(alarmMeta.getId());
+                int serviceInstanceId = Integer.parseInt(indicatorMetaInfo.getId());
                 ServiceInstanceInventory serviceInstanceInventory = serviceInstanceInventoryCache.get(serviceInstanceId);
                 ServiceInstanceMetaInAlarm instanceMetaInAlarm = new ServiceInstanceMetaInAlarm();
-                instanceMetaInAlarm.setIndicatorName(alarmMeta.getIndicatorName());
+                instanceMetaInAlarm.setIndicatorName(indicatorMetaInfo.getIndicatorName());
                 instanceMetaInAlarm.setId(serviceInstanceId);
                 instanceMetaInAlarm.setName(serviceInstanceInventory.getName());
                 metaInAlarm = instanceMetaInAlarm;
                 break;
             case ENDPOINT:
-                int endpointId = Integer.parseInt(alarmMeta.getId());
+                int endpointId = Integer.parseInt(indicatorMetaInfo.getId());
                 EndpointInventory endpointInventory = endpointInventoryCache.get(endpointId);
                 EndpointMetaInAlarm endpointMetaInAlarm = new EndpointMetaInAlarm();
-                endpointMetaInAlarm.setIndicatorName(alarmMeta.getIndicatorName());
+                endpointMetaInAlarm.setIndicatorName(indicatorMetaInfo.getIndicatorName());
                 endpointMetaInAlarm.setId(endpointId);
 
                 serviceId = endpointInventory.getServiceId();

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/alarm/AlarmMeta.java → oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/indicator/IndicatorMetaInfo.java

@@ -16,7 +16,7 @@
  *
  */
 
-package org.apache.skywalking.oap.server.core.alarm;
+package org.apache.skywalking.oap.server.core.analysis.indicator;
 
 import lombok.*;
 import org.apache.skywalking.oap.server.core.Const;
@@ -24,18 +24,18 @@ import org.apache.skywalking.oap.server.core.Const;
 /**
  * @author wusheng
  */
-public class AlarmMeta {
+public class IndicatorMetaInfo {
     @Setter @Getter private String indicatorName;
     @Setter @Getter private int scope;
     @Setter @Getter private String id;
 
-    public AlarmMeta(String indicatorName, int scope) {
+    public IndicatorMetaInfo(String indicatorName, int scope) {
         this.indicatorName = indicatorName;
         this.scope = scope;
         this.id = Const.EMPTY_STRING;
     }
 
-    public AlarmMeta(String indicatorName, int scope, String id) {
+    public IndicatorMetaInfo(String indicatorName, int scope, String id) {
         this.indicatorName = indicatorName;
         this.scope = scope;
         this.id = id;
@@ -48,4 +48,12 @@ public class AlarmMeta {
     public void setId(String id) {
         this.id = id;
     }
+
+    @Override public String toString() {
+        return "IndicatorMetaInfo{" +
+            "indicatorName='" + indicatorName + '\'' +
+            ", scope=" + scope +
+            ", id='" + id + '\'' +
+            '}';
+    }
 }

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/alarm/AlarmSupported.java → oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/indicator/WithMetadata.java

@@ -16,13 +16,13 @@
  *
  */
 
-package org.apache.skywalking.oap.server.core.alarm;
+package org.apache.skywalking.oap.server.core.analysis.indicator;
 
 /**
- * Alarm supported interface implementor could return the {@link AlarmMeta}
+ * Indicator, which implement this interface, could provide {@link IndicatorMetaInfo}.
  *
  * @author wusheng
  */
-public interface AlarmSupported {
-    AlarmMeta getAlarmMeta();
+public interface WithMetadata {
+    IndicatorMetaInfo getMeta();
 }

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/worker/AlarmNotifyWorker.java

@@ -18,9 +18,9 @@
 
 package org.apache.skywalking.oap.server.core.analysis.worker;
 
-import org.apache.skywalking.oap.server.core.alarm.AlarmEntrance;
-import org.apache.skywalking.oap.server.core.alarm.AlarmSupported;
-import org.apache.skywalking.oap.server.core.analysis.indicator.Indicator;
+import org.apache.skywalking.oap.server.core.alarm.*;
+import org.apache.skywalking.oap.server.core.analysis.indicator.*;
+import org.apache.skywalking.oap.server.core.analysis.indicator.WithMetadata;
 import org.apache.skywalking.oap.server.core.worker.AbstractWorker;
 import org.apache.skywalking.oap.server.library.module.ModuleManager;
 
@@ -40,7 +40,7 @@ public class AlarmNotifyWorker extends AbstractWorker<Indicator> {
     }
 
     @Override public void in(Indicator indicator) {
-        if (indicator instanceof AlarmSupported) {
+        if (indicator instanceof WithMetadata) {
             entrance.forward(indicator);
         }
     }

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/worker/ExportWorker.java

+/*
+ * 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
+ *
+ *     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.
+ *
+ */
+
+package org.apache.skywalking.oap.server.core.analysis.worker;
+
+import org.apache.skywalking.oap.server.core.analysis.indicator.*;
+import org.apache.skywalking.oap.server.core.exporter.*;
+import org.apache.skywalking.oap.server.core.worker.AbstractWorker;
+import org.apache.skywalking.oap.server.library.module.ModuleManager;
+
+/**
+ * @author wusheng
+ */
+public class ExportWorker extends AbstractWorker<Indicator> {
+    private ModuleManager moduleManager;
+    private MetricValuesExportService exportService;
+
+    public ExportWorker(int workerId, ModuleManager moduleManager) {
+        super(workerId);
+        this.moduleManager = moduleManager;
+    }
+
+    @Override public void in(Indicator indicator) {
+        if (exportService != null || moduleManager.has(ExporterModule.NAME)) {
+            if (indicator instanceof WithMetadata) {
+                if (exportService == null) {
+                    exportService = moduleManager.find(ExporterModule.NAME).provider().getService(MetricValuesExportService.class);
+                }
+                exportService.export(((WithMetadata)indicator).getMeta(), indicator);
+            }
+        }
+    }
+}

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/worker/IndicatorPersistentWorker.java

@@ -18,21 +18,16 @@
 
 package org.apache.skywalking.oap.server.core.analysis.worker;
 
-import java.util.Iterator;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Objects;
+import java.util.*;
 import org.apache.skywalking.apm.commons.datacarrier.DataCarrier;
 import org.apache.skywalking.apm.commons.datacarrier.consumer.*;
 import org.apache.skywalking.oap.server.core.UnexpectedException;
-import org.apache.skywalking.oap.server.core.analysis.data.EndOfBatchContext;
-import org.apache.skywalking.oap.server.core.analysis.data.MergeDataCache;
+import org.apache.skywalking.oap.server.core.analysis.data.*;
 import org.apache.skywalking.oap.server.core.analysis.indicator.Indicator;
 import org.apache.skywalking.oap.server.core.storage.IIndicatorDAO;
 import org.apache.skywalking.oap.server.core.worker.AbstractWorker;
 import org.apache.skywalking.oap.server.library.module.ModuleManager;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import org.slf4j.*;
 
 import static java.util.Objects.nonNull;
 
@@ -46,16 +41,19 @@ public class IndicatorPersistentWorker extends PersistenceWorker<Indicator, Merg
     private final String modelName;
     private final MergeDataCache<Indicator> mergeDataCache;
     private final IIndicatorDAO indicatorDAO;
-    private final AbstractWorker<Indicator> nextWorker;
+    private final AbstractWorker<Indicator> nextAlarmWorker;
+    private final AbstractWorker<Indicator> nextExportWorker;
     private final DataCarrier<Indicator> dataCarrier;
 
     IndicatorPersistentWorker(int workerId, String modelName, int batchSize, ModuleManager moduleManager,
-        IIndicatorDAO indicatorDAO, AbstractWorker<Indicator> nextWorker) {
+        IIndicatorDAO indicatorDAO, AbstractWorker<Indicator> nextAlarmWorker,
+        AbstractWorker<Indicator> nextExportWorker) {
         super(moduleManager, workerId, batchSize);
         this.modelName = modelName;
         this.mergeDataCache = new MergeDataCache<>();
         this.indicatorDAO = indicatorDAO;
-        this.nextWorker = nextWorker;
+        this.nextAlarmWorker = nextAlarmWorker;
+        this.nextExportWorker = nextExportWorker;
 
         String name = "INDICATOR_L2_AGGREGATION";
         int size = BulkConsumePool.Creator.recommendMaxSize() / 8;
@@ -117,8 +115,11 @@ public class IndicatorPersistentWorker extends PersistenceWorker<Indicator, Merg
                     batchCollection.add(indicatorDAO.prepareBatchInsert(modelName, data));
                 }
 
-                if (Objects.nonNull(nextWorker)) {
-                    nextWorker.in(data);
+                if (Objects.nonNull(nextAlarmWorker)) {
+                    nextAlarmWorker.in(data);
+                }
+                if (Objects.nonNull(nextExportWorker)) {
+                    nextExportWorker.in(data);
                 }
             } catch (Throwable t) {
                 logger.error(t.getMessage(), t);

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/worker/IndicatorProcess.java

@@ -74,8 +74,11 @@ public enum IndicatorProcess {
         AlarmNotifyWorker alarmNotifyWorker = new AlarmNotifyWorker(WorkerIdGenerator.INSTANCES.generate(), moduleManager);
         WorkerInstances.INSTANCES.put(alarmNotifyWorker.getWorkerId(), alarmNotifyWorker);
 
+        ExportWorker exportWorker = new ExportWorker(WorkerIdGenerator.INSTANCES.generate(), moduleManager);
+        WorkerInstances.INSTANCES.put(exportWorker.getWorkerId(), exportWorker);
+
         IndicatorPersistentWorker minutePersistentWorker = new IndicatorPersistentWorker(WorkerIdGenerator.INSTANCES.generate(), modelName,
-            1000, moduleManager, indicatorDAO, alarmNotifyWorker);
+            1000, moduleManager, indicatorDAO, alarmNotifyWorker, exportWorker);
         WorkerInstances.INSTANCES.put(minutePersistentWorker.getWorkerId(), minutePersistentWorker);
         persistentWorkers.add(minutePersistentWorker);
 
@@ -85,7 +88,7 @@ public enum IndicatorProcess {
     private IndicatorPersistentWorker worker(ModuleManager moduleManager,
         IIndicatorDAO indicatorDAO, String modelName) {
         IndicatorPersistentWorker persistentWorker = new IndicatorPersistentWorker(WorkerIdGenerator.INSTANCES.generate(), modelName,
-            1000, moduleManager, indicatorDAO, null);
+            1000, moduleManager, indicatorDAO, null, null);
         WorkerInstances.INSTANCES.put(persistentWorker.getWorkerId(), persistentWorker);
         persistentWorkers.add(persistentWorker);
 

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/exporter/ExporterModule.java

+/*
+ * 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
+ *
+ *     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.
+ *
+ */
+
+package org.apache.skywalking.oap.server.core.exporter;
+
+import org.apache.skywalking.oap.server.library.module.ModuleDefine;
+
+/**
+ * @author wusheng
+ */
+public class ExporterModule extends ModuleDefine {
+    public static final String NAME = "exporter";
+
+    public ExporterModule() {
+        super(NAME);
+    }
+
+    @Override public Class[] services() {
+        return new Class[] {MetricValuesExportService.class};
+    }
+}

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/exporter/MetricValuesExportService.java

+/*
+ * 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
+ *
+ *     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.
+ *
+ */
+
+package org.apache.skywalking.oap.server.core.exporter;
+
+import org.apache.skywalking.oap.server.core.analysis.indicator.*;
+import org.apache.skywalking.oap.server.library.module.Service;
+
+/**
+ * Export the metric value from indicators through this service, if provider exists.
+ *
+ * @author wusheng
+ */
+public interface MetricValuesExportService extends Service {
+    void export(IndicatorMetaInfo meta, Indicator indicator);
+}

oap-server/server-core/src/main/resources/META-INF/services/org.apache.skywalking.oap.server.library.module.ModuleDefine

@@ -20,4 +20,5 @@ org.apache.skywalking.oap.server.core.storage.StorageModule
 org.apache.skywalking.oap.server.core.cluster.ClusterModule
 org.apache.skywalking.oap.server.core.CoreModule
 org.apache.skywalking.oap.server.core.query.QueryModule
-org.apache.skywalking.oap.server.core.alarm.AlarmModule
\ No newline at end of file
+org.apache.skywalking.oap.server.core.alarm.AlarmModule
+org.apache.skywalking.oap.server.core.exporter.ExporterModule
\ No newline at end of file

oap-server/server-query-plugin/query-graphql-plugin/src/main/java/org/apache/skywalking/oap/query/graphql/GraphQLQueryHandler.java

@@ -30,6 +30,7 @@ import graphql.GraphQLError;
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;
+import java.lang.reflect.Type;
 import java.util.List;
 import java.util.Map;
 import javax.servlet.http.HttpServletRequest;
@@ -51,6 +52,8 @@ public class GraphQLQueryHandler extends JettyJsonHandler {
     private static final String MESSAGE = "message";
 
     private final Gson gson = new Gson();
+    private final Type mapOfStringObjectType = new TypeToken<Map<String, Object>>() {
+    }.getType();
 
     private final String path;
 
@@ -75,8 +78,7 @@ public class GraphQLQueryHandler extends JettyJsonHandler {
 
         JsonObject requestJson = gson.fromJson(request.toString(), JsonObject.class);
 
-        return execute(requestJson.get(QUERY).getAsString(), gson.fromJson(requestJson.get(VARIABLES), new TypeToken<Map<String, Object>>() {
-        }.getType()));
+        return execute(requestJson.get(QUERY).getAsString(), gson.fromJson(requestJson.get(VARIABLES), mapOfStringObjectType));
     }
 
     private JsonObject execute(String request, Map<String, Object> variables) {

pom.xml

@@ -17,7 +17,8 @@
   ~
   -->
 
-<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">
+<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>
 
     <groupId>org.apache.skywalking</groupId>
@@ -82,7 +83,6 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <compiler.version>1.8</compiler.version>
-        <scala.compiler.version>2.11.7</scala.compiler.version>
         <powermock.version>1.6.4</powermock.version>
         <checkstyle.version>6.18</checkstyle.version>
         <junit.version>4.12</junit.version>
@@ -114,13 +114,11 @@
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
-            <version>${junit.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-all</artifactId>
-            <version>${mockito-all.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
@@ -140,13 +138,13 @@
             <dependency>
                 <groupId>junit</groupId>
                 <artifactId>junit</artifactId>
-                <version>4.12</version>
+                <version>${junit.version}</version>
                 <scope>test</scope>
             </dependency>
             <dependency>
                 <groupId>org.mockito</groupId>
                 <artifactId>mockito-all</artifactId>
-                <version>1.10.19</version>
+                <version>${mockito-all.version}</version>
                 <scope>test</scope>
             </dependency>
             <dependency>