Support dynamic change SAMPLE_N_PER_3_SECS on java agent (#6232)

CHANGES.md

@@ -36,6 +36,7 @@ Release Notes.
 * Support reading segmentId and spanId with toolkit.
 * Fix RestTemplate plugin recording url tag with wrong port
 * Support collecting logs and forwarding through gRPC.
+* Support config `agent.sample_n_per_3_secs` can be changed in the runtime.
 
 #### OAP-Backend
 * Make meter receiver support MAL.

apm-protocol/apm-network/src/main/java/org/apache/skywalking/apm/network/trace/component/command/ConfigurationDiscoveryCommand.java

@@ -26,7 +26,7 @@ import org.apache.skywalking.apm.network.common.v3.KeyStringValuePair;
 public class ConfigurationDiscoveryCommand extends BaseCommand implements Serializable, Deserializable<ConfigurationDiscoveryCommand> {
     public static final Deserializable<ConfigurationDiscoveryCommand> DESERIALIZER = new ConfigurationDiscoveryCommand(
         "", "", new ArrayList<>());
-    public static final String NAME = ConfigurationDiscoveryCommand.class.getSimpleName();
+    public static final String NAME = "ConfigurationDiscoveryCommand";
 
     public static final String UUID_CONST_NAME = "UUID";
     public static final String SERIAL_NUMBER_CONST_NAME = "SerialNumber";

proto @ ce9e4e8b

-Subproject commit 101dc50429c98147b1109cb15c8a6c623e751759
+Subproject commit ce9e4e8bd9e552443cc970df67ee25f17ff0d3b8

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/commands/CommandExecutorService.java

@@ -21,9 +21,11 @@ import java.util.HashMap;
 import java.util.Map;
 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.commands.executor.ConfigurationDiscoveryCommandExecutor;
 import org.apache.skywalking.apm.agent.core.commands.executor.NoopCommandExecutor;
 import org.apache.skywalking.apm.agent.core.commands.executor.ProfileTaskCommandExecutor;
 import org.apache.skywalking.apm.network.trace.component.command.BaseCommand;
+import org.apache.skywalking.apm.network.trace.component.command.ConfigurationDiscoveryCommand;
 import org.apache.skywalking.apm.network.trace.component.command.ProfileTaskCommand;
 
 /**
@@ -43,6 +45,9 @@ public class CommandExecutorService implements BootService, CommandExecutor {
 
         // Profile task executor
         commandExecutorMap.put(ProfileTaskCommand.NAME, new ProfileTaskCommandExecutor());
+
+        //Get ConfigurationDiscoveryCommand executor.
+        commandExecutorMap.put(ConfigurationDiscoveryCommand.NAME, new ConfigurationDiscoveryCommandExecutor());
     }
 
     @Override

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/commands/executor/ConfigurationDiscoveryCommandExecutor.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.commands.executor;
+
+import org.apache.skywalking.apm.agent.core.boot.ServiceManager;
+import org.apache.skywalking.apm.agent.core.commands.CommandExecutionException;
+import org.apache.skywalking.apm.agent.core.commands.CommandExecutor;
+import org.apache.skywalking.apm.agent.core.conf.dynamic.ConfigurationDiscoveryService;
+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.network.trace.component.command.BaseCommand;
+import org.apache.skywalking.apm.network.trace.component.command.ConfigurationDiscoveryCommand;
+
+public class ConfigurationDiscoveryCommandExecutor implements CommandExecutor {
+
+    private static final ILog LOGGER = LogManager.getLogger(ConfigurationDiscoveryCommandExecutor.class);
+
+    @Override
+    public void execute(BaseCommand command) throws CommandExecutionException {
+        try {
+            ConfigurationDiscoveryCommand agentDynamicConfigurationCommand = (ConfigurationDiscoveryCommand) command;
+
+            ServiceManager.INSTANCE.findService(ConfigurationDiscoveryService.class)
+                                   .handleConfigurationDiscoveryCommand(agentDynamicConfigurationCommand);
+        } catch (Exception e) {
+            LOGGER.error(e, "Handle ConfigurationDiscoveryCommand error, command:{}", command.toString());
+        }
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/conf/Config.java

@@ -164,6 +164,10 @@ public class Config {
          */
         public static int GET_PROFILE_TASK_INTERVAL = 20;
 
+        /**
+         * Get agent dynamic config interval
+         */
+        public static int GET_AGENT_DYNAMIC_CONFIG_INTERVAL = 20;
     }
 
     public static class Profile {

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/conf/dynamic/AgentConfigChangeWatcher.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.conf.dynamic;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+@Getter
+public abstract class AgentConfigChangeWatcher {
+    // Config key, should match KEY in the Table of Agent Configuration Properties.
+    private final String propertyKey;
+
+    public AgentConfigChangeWatcher(String propertyKey) {
+        this.propertyKey = propertyKey;
+    }
+
+    /**
+     * Notify the watcher, the new value received.
+     *
+     * @param value of new.
+     */
+    public abstract void notify(ConfigChangeEvent value);
+
+    /**
+     * @return current value of current config.
+     */
+    public abstract String value();
+
+    @Override
+    public String toString() {
+        return "AgentConfigChangeWatcher{" +
+            "propertyKey='" + propertyKey + '\'' +
+            '}';
+    }
+
+    @Getter
+    @RequiredArgsConstructor
+    public static class ConfigChangeEvent {
+        private final String newValue;
+        private final EventType eventType;
+    }
+
+    public enum EventType {
+        ADD, MODIFY, DELETE
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/conf/dynamic/ConfigurationDiscoveryService.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.conf.dynamic;
+
+import io.grpc.Channel;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+import lombok.Getter;
+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.DefaultNamedThreadFactory;
+import org.apache.skywalking.apm.agent.core.boot.ServiceManager;
+import org.apache.skywalking.apm.agent.core.commands.CommandService;
+import org.apache.skywalking.apm.agent.core.conf.Config;
+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.remote.GRPCChannelListener;
+import org.apache.skywalking.apm.agent.core.remote.GRPCChannelManager;
+import org.apache.skywalking.apm.agent.core.remote.GRPCChannelStatus;
+import org.apache.skywalking.apm.network.language.agent.v3.ConfigurationDiscoveryServiceGrpc;
+import org.apache.skywalking.apm.network.language.agent.v3.ConfigurationSyncRequest;
+import org.apache.skywalking.apm.network.common.v3.Commands;
+import org.apache.skywalking.apm.network.common.v3.KeyStringValuePair;
+import org.apache.skywalking.apm.network.trace.component.command.ConfigurationDiscoveryCommand;
+import org.apache.skywalking.apm.util.RunnableWithExceptionProtection;
+import org.apache.skywalking.apm.util.StringUtil;
+
+import static org.apache.skywalking.apm.agent.core.conf.Config.Collector.GRPC_UPSTREAM_TIMEOUT;
+
+@DefaultImplementor
+public class ConfigurationDiscoveryService implements BootService, GRPCChannelListener {
+
+    /**
+     * UUID of the last return value.
+     */
+    private String uuid;
+    private final Register register = new Register();
+
+    private volatile ScheduledFuture<?> getDynamicConfigurationFuture;
+    private volatile GRPCChannelStatus status = GRPCChannelStatus.DISCONNECT;
+    private volatile ConfigurationDiscoveryServiceGrpc.ConfigurationDiscoveryServiceBlockingStub configurationDiscoveryServiceBlockingStub;
+
+    private static final ILog LOGGER = LogManager.getLogger(ConfigurationDiscoveryService.class);
+
+    @Override
+    public void statusChanged(final GRPCChannelStatus status) {
+        if (GRPCChannelStatus.CONNECTED.equals(status)) {
+            Channel channel = ServiceManager.INSTANCE.findService(GRPCChannelManager.class).getChannel();
+            configurationDiscoveryServiceBlockingStub = ConfigurationDiscoveryServiceGrpc.newBlockingStub(channel);
+        } else {
+            configurationDiscoveryServiceBlockingStub = null;
+        }
+        this.status = status;
+    }
+
+    @Override
+    public void prepare() throws Throwable {
+        ServiceManager.INSTANCE.findService(GRPCChannelManager.class).addChannelListener(this);
+    }
+
+    @Override
+    public void boot() throws Throwable {
+        getDynamicConfigurationFuture = Executors.newSingleThreadScheduledExecutor(
+            new DefaultNamedThreadFactory("ConfigurationDiscoveryService")
+        ).scheduleAtFixedRate(
+            new RunnableWithExceptionProtection(
+                this::getAgentDynamicConfig,
+                t -> LOGGER.error("Sync config from OAP error.", t)
+            ),
+            Config.Collector.GET_AGENT_DYNAMIC_CONFIG_INTERVAL,
+            Config.Collector.GET_AGENT_DYNAMIC_CONFIG_INTERVAL,
+            TimeUnit.SECONDS
+        );
+    }
+
+    @Override
+    public void onComplete() throws Throwable {
+
+    }
+
+    @Override
+    public void shutdown() throws Throwable {
+        if (getDynamicConfigurationFuture != null) {
+            getDynamicConfigurationFuture.cancel(true);
+        }
+    }
+
+    /**
+     * Register dynamic configuration watcher.
+     *
+     * @param watcher dynamic configuration watcher
+     */
+    public void registerAgentConfigChangeWatcher(AgentConfigChangeWatcher watcher) {
+        WatcherHolder holder = new WatcherHolder(watcher);
+        if (register.containsKey(holder.getKey())) {
+            throw new IllegalStateException("Duplicate register, watcher=" + watcher);
+        }
+        register.put(holder.getKey(), holder);
+    }
+
+    /**
+     * Process ConfigurationDiscoveryCommand and notify each configuration watcher.
+     *
+     * @param configurationDiscoveryCommand Describe dynamic configuration information
+     */
+    public void handleConfigurationDiscoveryCommand(ConfigurationDiscoveryCommand configurationDiscoveryCommand) {
+        final String responseUuid = configurationDiscoveryCommand.getUuid();
+        final List<KeyStringValuePair> config = configurationDiscoveryCommand.getConfig();
+
+        if (responseUuid != null && Objects.equals(this.uuid, responseUuid)) {
+            return;
+        }
+
+        config.forEach(property -> {
+            String propertyKey = property.getKey();
+            WatcherHolder holder = register.get(propertyKey);
+            if (holder != null) {
+                AgentConfigChangeWatcher watcher = holder.getWatcher();
+                String newPropertyValue = property.getValue();
+                if (StringUtil.isBlank(newPropertyValue)) {
+                    if (watcher.value() != null) {
+                        // Notify watcher, the new value is null with delete event type.
+                        watcher.notify(
+                            new AgentConfigChangeWatcher.ConfigChangeEvent(
+                                null, AgentConfigChangeWatcher.EventType.DELETE
+                            ));
+                    } else {
+                        // Don't need to notify, stay in null.
+                    }
+                } else {
+                    if (!newPropertyValue.equals(watcher.value())) {
+                        watcher.notify(new AgentConfigChangeWatcher.ConfigChangeEvent(
+                            newPropertyValue, AgentConfigChangeWatcher.EventType.MODIFY
+                        ));
+                    } else {
+                        // Don't need to notify, stay in the same config value.
+                    }
+                }
+            } else {
+                LOGGER.warn("Config {} from OAP, doesn't match any watcher, ignore.", propertyKey);
+            }
+        });
+        this.uuid = responseUuid;
+
+        LOGGER.trace("Current configurations after the sync, configurations:{}", register.toString());
+    }
+
+    /**
+     * get agent dynamic config through gRPC.
+     */
+    private void getAgentDynamicConfig() {
+        LOGGER.debug("ConfigurationDiscoveryService running, status:{}.", status);
+
+        if (GRPCChannelStatus.CONNECTED.equals(status)) {
+            try {
+                ConfigurationSyncRequest.Builder builder = ConfigurationSyncRequest.newBuilder();
+                builder.setService(Config.Agent.SERVICE_NAME);
+                if (null != uuid) {
+                    builder.setUuid(uuid);
+                }
+
+                if (configurationDiscoveryServiceBlockingStub != null) {
+                    final Commands commands = configurationDiscoveryServiceBlockingStub.withDeadlineAfter(
+                        GRPC_UPSTREAM_TIMEOUT, TimeUnit.SECONDS
+                    ).fetchConfigurations(builder.build());
+                    ServiceManager.INSTANCE.findService(CommandService.class).receiveCommand(commands);
+                }
+            } catch (Throwable t) {
+                LOGGER.error(t, "ConfigurationDiscoveryService execute fail.");
+                ServiceManager.INSTANCE.findService(GRPCChannelManager.class).reportError(t);
+            }
+        }
+    }
+
+    /**
+     * Local dynamic configuration center.
+     */
+    public static class Register {
+        private final Map<String, WatcherHolder> register = new HashMap<>();
+
+        private boolean containsKey(String key) {
+            return register.containsKey(key);
+        }
+
+        private void put(String key, WatcherHolder holder) {
+            register.put(key, holder);
+        }
+
+        public WatcherHolder get(String name) {
+            return register.get(name);
+        }
+
+        @Override
+        public String toString() {
+            ArrayList<String> registerTableDescription = new ArrayList<>(register.size());
+            register.forEach((key, holder) -> {
+                AgentConfigChangeWatcher watcher = holder.getWatcher();
+                registerTableDescription.add(new StringBuilder().append("key:")
+                                                                .append(key)
+                                                                .append("value(current):")
+                                                                .append(watcher.value()).toString());
+            });
+            return registerTableDescription.stream().collect(Collectors.joining(",", "[", "]"));
+        }
+    }
+
+    @Getter
+    private static class WatcherHolder {
+        private final AgentConfigChangeWatcher watcher;
+        private final String key;
+
+        public WatcherHolder(AgentConfigChangeWatcher watcher) {
+            this.watcher = watcher;
+            this.key = watcher.getPropertyKey();
+        }
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/sampling/SamplingRateWatcher.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.sampling;
+
+import java.util.concurrent.atomic.AtomicInteger;
+import org.apache.skywalking.apm.agent.core.conf.Config;
+import org.apache.skywalking.apm.agent.core.conf.dynamic.AgentConfigChangeWatcher;
+import org.apache.skywalking.apm.agent.core.logging.api.ILog;
+import org.apache.skywalking.apm.agent.core.logging.api.LogManager;
+
+public class SamplingRateWatcher extends AgentConfigChangeWatcher {
+    private static final ILog LOGGER = LogManager.getLogger(SamplingRateWatcher.class);
+
+    private final AtomicInteger samplingRate;
+    private final SamplingService samplingService;
+
+    public SamplingRateWatcher(final String propertyKey, SamplingService samplingService) {
+        super(propertyKey);
+        this.samplingRate = new AtomicInteger(getDefaultValue());
+        this.samplingService = samplingService;
+    }
+
+    private void activeSetting(String config) {
+        if (LOGGER.isDebugEnable()) {
+            LOGGER.debug("Updating using new static config: {}", config);
+        }
+        try {
+            this.samplingRate.set(Integer.parseInt(config));
+
+            /*
+             * We need to notify samplingService the samplingRate changed.
+             */
+            samplingService.handleSamplingRateChanged();
+        } catch (NumberFormatException ex) {
+            LOGGER.error(ex, "Cannot load {} from: {}", getPropertyKey(), config);
+        }
+    }
+
+    @Override
+    public void notify(final ConfigChangeEvent value) {
+        if (EventType.DELETE.equals(value.getEventType())) {
+            activeSetting(String.valueOf(getDefaultValue()));
+        } else {
+            activeSetting(value.getNewValue());
+        }
+    }
+
+    @Override
+    public String value() {
+        return String.valueOf(samplingRate.get());
+    }
+
+    private int getDefaultValue() {
+        return Config.Agent.SAMPLE_N_PER_3_SECS;
+    }
+
+    public int getSamplingRate() {
+        return samplingRate.get();
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/sampling/SamplingService.java

@@ -26,7 +26,9 @@ import java.util.concurrent.atomic.AtomicInteger;
 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.DefaultNamedThreadFactory;
+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.conf.dynamic.ConfigurationDiscoveryService;
 import org.apache.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.apache.skywalking.apm.agent.core.logging.api.ILog;
 import org.apache.skywalking.apm.agent.core.logging.api.LogManager;
@@ -47,30 +49,19 @@ public class SamplingService implements BootService {
     private volatile AtomicInteger samplingFactorHolder;
     private volatile ScheduledFuture<?> scheduledFuture;
 
+    private SamplingRateWatcher samplingRateWatcher;
+
     @Override
     public void prepare() {
-
+        samplingRateWatcher = new SamplingRateWatcher("agent.sample_n_per_3_secs", this);
     }
 
     @Override
     public void boot() {
-        if (scheduledFuture != null) {
-            /*
-             * If {@link #boot()} invokes twice, mostly in test cases,
-             * cancel the old one.
-             */
-            scheduledFuture.cancel(true);
-        }
-        if (Config.Agent.SAMPLE_N_PER_3_SECS > 0) {
-            on = true;
-            this.resetSamplingFactor();
-            ScheduledExecutorService service = Executors.newSingleThreadScheduledExecutor(
-                new DefaultNamedThreadFactory("SamplingService"));
-            scheduledFuture = service.scheduleAtFixedRate(new RunnableWithExceptionProtection(
-                this::resetSamplingFactor, t -> LOGGER.error("unexpected exception.", t)), 0, 3, TimeUnit.SECONDS);
-            LOGGER.debug(
-                "Agent sampling mechanism started. Sample {} traces in 3 seconds.", Config.Agent.SAMPLE_N_PER_3_SECS);
-        }
+        ServiceManager.INSTANCE.findService(ConfigurationDiscoveryService.class)
+                               .registerAgentConfigChangeWatcher(samplingRateWatcher);
+
+        handleSamplingRateChanged();
     }
 
     @Override
@@ -92,7 +83,7 @@ public class SamplingService implements BootService {
     public boolean trySampling(String operationName) {
         if (on) {
             int factor = samplingFactorHolder.get();
-            if (factor < Config.Agent.SAMPLE_N_PER_3_SECS) {
+            if (factor < samplingRateWatcher.getSamplingRate()) {
                 return samplingFactorHolder.compareAndSet(factor, factor + 1);
             } else {
                 return false;
@@ -114,4 +105,31 @@ public class SamplingService implements BootService {
     private void resetSamplingFactor() {
         samplingFactorHolder = new AtomicInteger(0);
     }
-}
+
+    /**
+     * Handle the samplingRate changed.
+     */
+    void handleSamplingRateChanged() {
+        if (samplingRateWatcher.getSamplingRate() > 0) {
+            if (!on) {
+                on = true;
+                this.resetSamplingFactor();
+                ScheduledExecutorService service = Executors.newSingleThreadScheduledExecutor(
+                    new DefaultNamedThreadFactory("SamplingService"));
+                scheduledFuture = service.scheduleAtFixedRate(new RunnableWithExceptionProtection(
+                    this::resetSamplingFactor, t -> LOGGER.error("unexpected exception.", t)), 0, 3, TimeUnit.SECONDS);
+                LOGGER.debug(
+                    "Agent sampling mechanism started. Sample {} traces in 3 seconds.",
+                    samplingRateWatcher.getSamplingRate()
+                );
+            }
+        } else {
+            if (on) {
+                if (scheduledFuture != null) {
+                    scheduledFuture.cancel(true);
+                }
+                on = false;
+            }
+        }
+    }
+}
\ No newline at end of file

apm-sniffer/apm-agent-core/src/main/resources/META-INF/services/org.apache.skywalking.apm.agent.core.boot.BootService

@@ -32,4 +32,5 @@ org.apache.skywalking.apm.agent.core.profile.ProfileTaskExecutionService
 org.apache.skywalking.apm.agent.core.meter.MeterService
 org.apache.skywalking.apm.agent.core.meter.MeterSender
 org.apache.skywalking.apm.agent.core.context.status.StatusCheckService
-org.apache.skywalking.apm.agent.core.remote.LogReportServiceClient
\ No newline at end of file
+org.apache.skywalking.apm.agent.core.remote.LogReportServiceClient
+org.apache.skywalking.apm.agent.core.conf.dynamic.ConfigurationDiscoveryService
\ No newline at end of file

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

@@ -58,7 +58,7 @@ public class ServiceManagerTest {
     public void testServiceDependencies() throws Exception {
         HashMap<Class, BootService> registryService = getFieldValue(ServiceManager.INSTANCE, "bootedServices");
 
-        assertThat(registryService.size(), is(17));
+        assertThat(registryService.size(), is(18));
 
         assertTraceSegmentServiceClient(ServiceManager.INSTANCE.findService(TraceSegmentServiceClient.class));
         assertContextManager(ServiceManager.INSTANCE.findService(ContextManager.class));
@@ -107,7 +107,7 @@ public class ServiceManagerTest {
         assertNotNull(service);
 
         List<GRPCChannelListener> listeners = getFieldValue(service, "listeners");
-        assertEquals(listeners.size(), 7);
+        assertEquals(listeners.size(), 8);
     }
 
     private void assertSamplingService(SamplingService service) {

apm-sniffer/apm-agent-core/src/test/java/org/apache/skywalking/apm/agent/core/sampling/SamplingRateWatcherTest.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.sampling;
+
+import org.apache.skywalking.apm.agent.core.conf.dynamic.AgentConfigChangeWatcher;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.powermock.reflect.Whitebox;
+
+public class SamplingRateWatcherTest {
+    private SamplingService samplingService = new SamplingService();
+
+    @Before
+    public void setUp() {
+        samplingService.prepare();
+    }
+
+    @Test
+    public void testConfigModifyEvent() {
+        SamplingRateWatcher samplingRateWatcher = Whitebox.getInternalState(
+            samplingService, "samplingRateWatcher");
+        samplingRateWatcher.notify(new AgentConfigChangeWatcher.ConfigChangeEvent(
+            "10",
+            AgentConfigChangeWatcher.EventType.MODIFY
+        ));
+        Assert.assertEquals(10, samplingRateWatcher.getSamplingRate());
+        Assert.assertEquals("agent.sample_n_per_3_secs", samplingRateWatcher.getPropertyKey());
+    }
+
+    @Test
+    public void testConfigDeleteEvent() {
+        SamplingRateWatcher samplingRateWatcher = Whitebox.getInternalState(
+            samplingService, "samplingRateWatcher");
+        samplingRateWatcher.notify(new AgentConfigChangeWatcher.ConfigChangeEvent(
+            null,
+            AgentConfigChangeWatcher.EventType.DELETE
+        ));
+        Assert.assertEquals("agent.sample_n_per_3_secs", samplingRateWatcher.getPropertyKey());
+    }
+}

apm-sniffer/optional-plugins/trace-ignore-plugin/src/main/java/org/apache/skywalking/apm/plugin/trace/ignore/TraceIgnoreExtendService.java

@@ -47,6 +47,7 @@ public class TraceIgnoreExtendService extends SamplingService {
 
     @Override
     public void prepare() {
+        super.prepare();
     }
 
     @Override

apm-sniffer/optional-plugins/trace-ignore-plugin/src/test/java/org/apache/skywalking/apm/plugin/trace/ignore/TraceIgnoreTest.java

@@ -29,6 +29,7 @@ import org.junit.Assert;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.contrib.java.lang.system.EnvironmentVariables;
+import org.powermock.reflect.Whitebox;
 
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -51,8 +52,10 @@ public class TraceIgnoreTest {
     @Test
     public void testTraceIgnore() {
         SamplingService service = ServiceManager.INSTANCE.findService(SamplingService.class);
-        IgnoreConfig.Trace.IGNORE_PATH = "/eureka/**";
-        service.boot();
+        Whitebox.setInternalState(
+            service, "patterns",
+            new String[] {"/eureka/**"}
+        );
 
         Assert.assertFalse(service.trySampling("/eureka/apps"));
         Assert.assertTrue(service.trySampling("/consul/apps"));

docs/en/setup/service-agent/java-agent/README.md

@@ -94,6 +94,7 @@ property key | Description | Default |
 `collector.backend_service`|Collector SkyWalking trace receiver service addresses.|`127.0.0.1:11800`|
 `collector.grpc_upstream_timeout`|How long grpc client will timeout in sending data to upstream. Unit is second.|`30` seconds|
 `collector.get_profile_task_interval`|Sniffer get profile task list interval.|`20`|
+`collector.get_agent_dynamic_config_interval`|Sniffer get agent dynamic config interval|`20`|
 `logging.level`|Log level: TRACE, DEBUG, INFO, WARN, ERROR, OFF. Default is info.|`INFO`|
 `logging.file_name`|Log file name.|`skywalking-api.log`|
 `logging.output`| Log output. Default is FILE. Use CONSOLE means output to stdout. |`FILE`|

oap-server/server-bootstrap/src/main/resources/application.yml

@@ -415,6 +415,6 @@ health-checker:
     checkIntervalSeconds: ${SW_HEALTH_CHECKER_INTERVAL_SECONDS:5}
 
 configuration-discovery:
-  selector: ${SW_CONFIGURATION_DISCOVERY:-}
+  selector: ${SW_CONFIGURATION_DISCOVERY:default}
   default:
     disableMessageDigest: ${SW_DISABLE_MESSAGE_DIGEST:false}

oap-server/server-receiver-plugin/configuration-discovery-receiver-plugin/src/main/java/org/apache/skywalking/oap/server/recevier/configuration/discovery/handler/grpc/ConfigurationDiscoveryServiceHandler.java

@@ -24,8 +24,8 @@ import java.util.List;
 import java.util.Objects;
 import java.util.UUID;
 import lombok.extern.slf4j.Slf4j;
-import org.apache.skywalking.apm.network.agent.dynamic.configuration.v3.ConfigurationDiscoveryServiceGrpc;
-import org.apache.skywalking.apm.network.agent.dynamic.configuration.v3.ConfigurationSyncRequest;
+import org.apache.skywalking.apm.network.language.agent.v3.ConfigurationDiscoveryServiceGrpc;
+import org.apache.skywalking.apm.network.language.agent.v3.ConfigurationSyncRequest;
 import org.apache.skywalking.apm.network.common.v3.Commands;
 import org.apache.skywalking.apm.network.common.v3.KeyStringValuePair;
 import org.apache.skywalking.apm.network.trace.component.command.ConfigurationDiscoveryCommand;