customcontrol-add behavior limits and conflict warning logs with new unit tests

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/block/RuleConstant.java

@@ -50,6 +50,10 @@ public final class RuleConstant {
     public static final int CONTROL_BEHAVIOR_WARM_UP = 1;
     public static final int CONTROL_BEHAVIOR_RATE_LIMITER = 2;
     public static final int CONTROL_BEHAVIOR_WARM_UP_RATE_LIMITER = 3;
+    /**
+     * User-defined control behavior values MUST be >= 256 (0x100)
+     */
+    public static final int CONTROL_BEHAVIOR_USER_DEFINED_MIN = 0x100; // 256
 
     public static final int DEFAULT_BLOCK_STRATEGY = 0;
     public static final int TRY_AGAIN_BLOCK_STRATEGY = 1;

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/block/flow/FlowRuleUtil.java

@@ -20,15 +20,18 @@
 import com.alibaba.csp.sentinel.slots.block.RuleConstant;
 import com.alibaba.csp.sentinel.slots.block.RuleManager;
 import com.alibaba.csp.sentinel.slots.block.flow.controller.DefaultController;
-import com.alibaba.csp.sentinel.slots.block.flow.controller.ThrottlingController;
-import com.alibaba.csp.sentinel.slots.block.flow.controller.WarmUpController;
-import com.alibaba.csp.sentinel.slots.block.flow.controller.WarmUpRateLimiterController;
 import com.alibaba.csp.sentinel.util.StringUtil;
 import com.alibaba.csp.sentinel.util.function.Function;
 import com.alibaba.csp.sentinel.util.function.Predicate;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
 import java.util.Map.Entry;
+import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 
 /**
@@ -132,18 +135,9 @@ public static <K> Map<K, List<FlowRule>> buildFlowRuleMap(List<FlowRule> list, F
 
     private static TrafficShapingController generateRater(/*@Valid*/ FlowRule rule) {
         if (rule.getGrade() == RuleConstant.FLOW_GRADE_QPS) {
-            switch (rule.getControlBehavior()) {
-                case RuleConstant.CONTROL_BEHAVIOR_WARM_UP:
-                    return new WarmUpController(rule.getCount(), rule.getWarmUpPeriodSec(),
-                            ColdFactorProperty.coldFactor);
-                case RuleConstant.CONTROL_BEHAVIOR_RATE_LIMITER:
-                    return new ThrottlingController(rule.getMaxQueueingTimeMs(), rule.getCount());
-                case RuleConstant.CONTROL_BEHAVIOR_WARM_UP_RATE_LIMITER:
-                    return new WarmUpRateLimiterController(rule.getCount(), rule.getWarmUpPeriodSec(),
-                            rule.getMaxQueueingTimeMs(), ColdFactorProperty.coldFactor);
-                case RuleConstant.CONTROL_BEHAVIOR_DEFAULT:
-                default:
-                    // Default mode or unknown mode: default traffic shaping controller (fast-reject).
+            TrafficShapingControllerFactory trafficShapingControllerFactory = TrafficShapingControllerFactories.get(rule.getControlBehavior());
+            if (trafficShapingControllerFactory != null) {
+                return trafficShapingControllerFactory.create(rule);
             }
         }
         return new DefaultController(rule.getCount(), rule.getGrade());

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/block/flow/LoggingTrafficShapingControllerFactory.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 1999-2024 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://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 com.alibaba.csp.sentinel.slots.block.flow;
+
+import com.alibaba.csp.sentinel.log.RecordLog;
+
+import java.util.Objects;
+
+public class LoggingTrafficShapingControllerFactory implements TrafficShapingControllerFactory {
+
+    private final TrafficShapingControllerFactory delegate;
+
+    public LoggingTrafficShapingControllerFactory(TrafficShapingControllerFactory delegate) {
+        this.delegate = Objects.requireNonNull(delegate, "delegate must be not null.");
+    }
+
+    @Override
+    public TrafficShapingController create(FlowRule rule) {
+        RecordLog.debug("Creating traffic shaping controller '" + delegate.getClass().getName() + "' for rule: " + rule);
+        return delegate.create(rule);
+    }
+
+    @Override
+    public int getControlBehavior() {
+        return delegate.getControlBehavior();
+    }
+}

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/block/flow/TrafficShapingControllerFactories.java

@@ -0,0 +1,101 @@
+/*
+ * Copyright 1999-2024 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://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 com.alibaba.csp.sentinel.slots.block.flow;
+
+import com.alibaba.csp.sentinel.log.RecordLog;
+import com.alibaba.csp.sentinel.slots.block.RuleConstant;
+import com.alibaba.csp.sentinel.spi.SpiLoader;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.function.BinaryOperator;
+import java.util.stream.Collectors;
+
+public class TrafficShapingControllerFactories {
+
+    private static final Map<Integer, TrafficShapingControllerFactory> FACTORIES;
+
+    static {
+        FACTORIES = initFactories();
+    }
+
+    /**
+     * Using existing factory if the factory with the same control behavior already exists, because the existing factory has higher priority
+     */
+    private static BinaryOperator<TrafficShapingControllerFactory> usingExisting() {
+        return (existing, replacement) -> {
+            RecordLog.warn("[TrafficShapingControllerFactories] Duplicate control behavior [{}], " +
+                    "using existing factory [{}], ignoring [{}]",
+                    existing.getControlBehavior(),
+                    existing.getClass().getName(),
+                    replacement.getClass().getName());
+            return existing;
+        };
+    }
+
+    private static TrafficShapingControllerFactory logging(TrafficShapingControllerFactory factory) {
+        return new LoggingTrafficShapingControllerFactory(factory);
+    }
+
+    /**
+     * Validates the control behavior namespace of a factory.
+     */
+    private static void validateControlBehavior(TrafficShapingControllerFactory factory) {
+        int controlBehavior = factory.getControlBehavior();
+
+        // User-defined factories must not use reserved range [0, 255]
+        if (!factory.isBuiltIn() && isReservedControlBehavior(controlBehavior)) {
+            throw new IllegalArgumentException(String.format(
+                    "Invalid control behavior [%d] for factory [%s]. " +
+                    "Control behavior values in range [0, %d] are reserved for Sentinel built-in implementations. " +
+                    "User-defined factories must use values >= %d to ensure compatibility with future Sentinel upgrades.",
+                    controlBehavior,
+                    factory.getClass().getName(),
+                    RuleConstant.CONTROL_BEHAVIOR_USER_DEFINED_MIN - 1,
+                    RuleConstant.CONTROL_BEHAVIOR_USER_DEFINED_MIN));
+        }
+
+        RecordLog.info("[TrafficShapingControllerFactories] Registered factory [{}] for control behavior [{}]",
+                factory.getClass().getName(), controlBehavior);
+    }
+
+    private static Map<Integer, TrafficShapingControllerFactory> initFactories() {
+        List<TrafficShapingControllerFactory> factories = SpiLoader.of(TrafficShapingControllerFactory.class)
+                .loadInstanceListSorted();
+        // Validate all factories
+        for (TrafficShapingControllerFactory factory : factories) {
+            validateControlBehavior(factory);
+        }
+        return factories.stream()
+                .collect(Collectors.toMap(
+                        TrafficShapingControllerFactory::getControlBehavior,
+                        TrafficShapingControllerFactories::logging,
+                        usingExisting(),
+                        HashMap::new));
+    }
+
+    public static TrafficShapingControllerFactory get(int controlBehavior) {
+        return FACTORIES.get(controlBehavior);
+    }
+
+    private TrafficShapingControllerFactories() {
+    }
+
+    public static boolean isReservedControlBehavior(int controlBehavior) {
+        return controlBehavior < RuleConstant.CONTROL_BEHAVIOR_USER_DEFINED_MIN;
+    }
+}

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/block/flow/TrafficShapingControllerFactory.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 1999-2024 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://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 com.alibaba.csp.sentinel.slots.block.flow;
+
+/**
+ * a factory interface to create TrafficShapingController instance
+ */
+public interface TrafficShapingControllerFactory {
+
+    /**
+     * create a TrafficShapingController instance
+     * @param rule flow rule
+     * @return a new TrafficShapingController instance
+     */
+    TrafficShapingController create(FlowRule rule);
+
+    /**
+     * get the factory control behavior
+     * @return the control behavior
+     */
+    int getControlBehavior();
+
+    /**
+     * Indicates whether this factory is a built-in Sentinel implementation.
+     * Built-in factories are allowed to use control behavior values in the reserved range [0, 255].
+     * User-defined factories should return {@code false} (default) and use values >= 256.
+     *
+     * This method is used internally for validation during factory registration to ensure
+     * proper namespace separation and prevent conflicts.
+     *
+     * @return {@code true} if this is a Sentinel built-in factory, {@code false} for user-defined implementations
+     */
+    default boolean isBuiltIn() {
+        return false;
+    }
+}

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/block/flow/controller/DefaultControllerFactory.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 1999-2024 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://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 com.alibaba.csp.sentinel.slots.block.flow.controller;
+
+import com.alibaba.csp.sentinel.slots.block.RuleConstant;
+import com.alibaba.csp.sentinel.slots.block.flow.FlowRule;
+import com.alibaba.csp.sentinel.slots.block.flow.TrafficShapingController;
+import com.alibaba.csp.sentinel.slots.block.flow.TrafficShapingControllerFactory;
+
+public class DefaultControllerFactory implements TrafficShapingControllerFactory {
+
+    @Override
+    public TrafficShapingController create(FlowRule rule) {
+        return new DefaultController(rule.getCount(), rule.getGrade());
+    }
+
+    @Override
+    public int getControlBehavior() {
+        return RuleConstant.CONTROL_BEHAVIOR_DEFAULT;
+    }
+
+    @Override
+    public boolean isBuiltIn() {
+        return true;
+    }
+}

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/block/flow/controller/ThrottlingControllerFactory.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 1999-2024 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://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 com.alibaba.csp.sentinel.slots.block.flow.controller;
+
+import com.alibaba.csp.sentinel.slots.block.RuleConstant;
+import com.alibaba.csp.sentinel.slots.block.flow.FlowRule;
+import com.alibaba.csp.sentinel.slots.block.flow.TrafficShapingController;
+import com.alibaba.csp.sentinel.slots.block.flow.TrafficShapingControllerFactory;
+
+public class ThrottlingControllerFactory implements TrafficShapingControllerFactory {
+
+    @Override
+    public TrafficShapingController create(FlowRule rule) {
+        return new ThrottlingController(rule.getMaxQueueingTimeMs(), rule.getCount());
+    }
+
+    @Override
+    public int getControlBehavior() {
+        return RuleConstant.CONTROL_BEHAVIOR_RATE_LIMITER;
+    }
+
+    @Override
+    public boolean isBuiltIn() {
+        return true;
+    }
+}

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/block/flow/controller/WarmUpControllerFactory.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 1999-2024 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://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 com.alibaba.csp.sentinel.slots.block.flow.controller;
+
+import com.alibaba.csp.sentinel.config.SentinelConfig;
+import com.alibaba.csp.sentinel.slots.block.RuleConstant;
+import com.alibaba.csp.sentinel.slots.block.flow.FlowRule;
+import com.alibaba.csp.sentinel.slots.block.flow.TrafficShapingController;
+import com.alibaba.csp.sentinel.slots.block.flow.TrafficShapingControllerFactory;
+
+public class WarmUpControllerFactory implements TrafficShapingControllerFactory {
+
+    static volatile int coldFactor = SentinelConfig.coldFactor();
+
+    @Override
+    public TrafficShapingController create(FlowRule rule) {
+        return new WarmUpController(rule.getCount(), rule.getWarmUpPeriodSec(), coldFactor);
+    }
+
+    @Override
+    public int getControlBehavior() {
+        return RuleConstant.CONTROL_BEHAVIOR_WARM_UP;
+    }
+
+    @Override
+    public boolean isBuiltIn() {
+        return true;
+    }
+}