Add basic demo for Sentinel Spring WebFlux adapter

Signed-off-by: Eric Zhao <sczyh16@gmail.com>

sentinel-demo/pom.xml

@@ -30,6 +30,7 @@
         <module>sentinel-demo-slot-chain-spi</module>
         <module>sentinel-demo-cluster</module>
         <module>sentinel-demo-command-handler</module>
+        <module>sentinel-demo-spring-webflux</module>
     </modules>
 
     <dependencies>

sentinel-demo/sentinel-demo-spring-webflux/pom.xml

@@ -0,0 +1,44 @@
+<?xml version="1.0" encoding="UTF-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">
+    <parent>
+        <artifactId>sentinel-demo</artifactId>
+        <groupId>com.alibaba.csp</groupId>
+        <version>1.5.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>sentinel-demo-spring-webflux</artifactId>
+
+    <properties>
+        <spring.boot.version>2.1.3.RELEASE</spring.boot.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.alibaba.csp</groupId>
+            <artifactId>sentinel-core</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.alibaba.csp</groupId>
+            <artifactId>sentinel-transport-simple-http</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.alibaba.csp</groupId>
+            <artifactId>sentinel-spring-webflux-adapter</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-webflux</artifactId>
+            <version>${spring.boot.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-data-redis-reactive</artifactId>
+            <version>${spring.boot.version}</version>
+        </dependency>
+    </dependencies>
+</project>

sentinel-demo/sentinel-demo-spring-webflux/src/main/java/com/alibaba/csp/sentinel/demo/spring/webflux/WebFluxDemoApplication.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 1999-2019 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
+ *
+ *      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 com.alibaba.csp.sentinel.demo.spring.webflux;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+/**
+ * <p>A demo for Spring WebFlux reactive application.</p>
+ *
+ * <p>To integrate with Sentinel dashboard, you can run the demo with the parameters (an example):
+ * <code>-Dproject.name=WebFluxDemoApplication -Dcsp.sentinel.dashboard.server=localhost:8080
+ * -Dcsp.sentinel.api.port=8720
+ * </code>
+ * </p>
+ *
+ * @author Eric Zhao
+ */
+@SpringBootApplication
+public class WebFluxDemoApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(WebFluxDemoApplication.class, args);
+    }
+}

sentinel-demo/sentinel-demo-spring-webflux/src/main/java/com/alibaba/csp/sentinel/demo/spring/webflux/config/RedisConfig.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 1999-2018 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
+ *
+ *      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 com.alibaba.csp.sentinel.demo.spring.webflux.config;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.data.redis.connection.ReactiveRedisConnectionFactory;
+import org.springframework.data.redis.core.ReactiveRedisTemplate;
+import org.springframework.data.redis.serializer.RedisSerializationContext;
+import org.springframework.data.redis.serializer.StringRedisSerializer;
+
+/**
+ * @author Eric Zhao
+ */
+@Configuration
+public class RedisConfig {
+
+    @Bean
+    public ReactiveRedisTemplate<String, String> stringReactiveRedisTemplate(ReactiveRedisConnectionFactory connectionFactory){
+        RedisSerializationContext<String, String> serializationContext = RedisSerializationContext
+            .<String, String>newSerializationContext(new StringRedisSerializer())
+            .hashKey(new StringRedisSerializer())
+            .hashValue(new StringRedisSerializer())
+            .build();
+        return new ReactiveRedisTemplate<>(connectionFactory, serializationContext);
+    }
+}

sentinel-demo/sentinel-demo-spring-webflux/src/main/java/com/alibaba/csp/sentinel/demo/spring/webflux/config/WebFluxConfig.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright 1999-2018 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
+ *
+ *      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 com.alibaba.csp.sentinel.demo.spring.webflux.config;
+
+import java.util.Collections;
+import java.util.List;
+
+import com.alibaba.csp.sentinel.adapter.spring.webflux.SentinelWebFluxFilter;
+import com.alibaba.csp.sentinel.adapter.spring.webflux.exception.SentinelBlockExceptionHandler;
+
+import org.springframework.beans.factory.ObjectProvider;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.annotation.Order;
+import org.springframework.http.codec.ServerCodecConfigurer;
+import org.springframework.web.reactive.result.view.ViewResolver;
+
+/**
+ * @author Eric Zhao
+ */
+@Configuration
+public class WebFluxConfig {
+
+    private final List<ViewResolver> viewResolvers;
+    private final ServerCodecConfigurer serverCodecConfigurer;
+
+    public WebFluxConfig(ObjectProvider<List<ViewResolver>> viewResolversProvider,
+                         ServerCodecConfigurer serverCodecConfigurer) {
+        this.viewResolvers = viewResolversProvider.getIfAvailable(Collections::emptyList);
+        this.serverCodecConfigurer = serverCodecConfigurer;
+    }
+
+    @Bean
+    @Order(-1)
+    public SentinelBlockExceptionHandler sentinelBlockExceptionHandler() {
+        // Register the block exception handler for Spring WebFlux.
+        return new SentinelBlockExceptionHandler(viewResolvers, serverCodecConfigurer);
+    }
+
+    @Bean
+    @Order(-1)
+    public SentinelWebFluxFilter sentinelWebFluxFilter() {
+        // Register the Sentinel WebFlux filter.
+        return new SentinelWebFluxFilter();
+    }
+}

sentinel-demo/sentinel-demo-spring-webflux/src/main/java/com/alibaba/csp/sentinel/demo/spring/webflux/controller/BazController.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 1999-2019 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
+ *
+ *      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 com.alibaba.csp.sentinel.demo.spring.webflux.controller;
+
+import com.alibaba.csp.sentinel.adapter.reactor.SentinelReactorTransformer;
+import com.alibaba.csp.sentinel.demo.spring.webflux.service.BazService;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Mono;
+
+/**
+ * @author Eric Zhao
+ */
+@RestController
+@RequestMapping(value = "/baz")
+public class BazController {
+
+    @Autowired
+    private BazService bazService;
+
+    @GetMapping("/{id}")
+    public Mono<String> apiGetValue(@PathVariable("id") Long id) {
+        return bazService.getById(id)
+            .transform(new SentinelReactorTransformer<>("BazService:getById"));
+    }
+
+    @PostMapping("/{id}")
+    public Mono<Boolean> apiSetValue(@PathVariable("id") Long id, @RequestBody String value) {
+        return bazService.setValue(id, value)
+            .transform(new SentinelReactorTransformer<>("BazService:setValue"));
+    }
+}

sentinel-demo/sentinel-demo-spring-webflux/src/main/java/com/alibaba/csp/sentinel/demo/spring/webflux/controller/FooController.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright 1999-2019 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
+ *
+ *      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 com.alibaba.csp.sentinel.demo.spring.webflux.controller;
+
+import com.alibaba.csp.sentinel.adapter.reactor.SentinelReactorTransformer;
+import com.alibaba.csp.sentinel.demo.spring.webflux.service.FooService;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.server.reactive.ServerHttpResponse;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+/**
+ * @author Eric Zhao
+ */
+@RestController
+@RequestMapping(value = "/foo")
+public class FooController {
+
+    @Autowired
+    private FooService fooService;
+
+    @GetMapping("/single")
+    public Mono<String> apiNormalSingle() {
+        return fooService.emitSingle()
+            // transform the publisher here.
+            .transform(new SentinelReactorTransformer<>("demo_foo_normal_single"));
+    }
+
+    @GetMapping("/flux")
+    public Flux<Integer> apiNormalFlux() {
+        return fooService.emitMultiple()
+            .transform(new SentinelReactorTransformer<>("demo_foo_normal_flux"));
+    }
+
+    @GetMapping("/slow")
+    public Mono<String> apiDoSomethingSlow(ServerHttpResponse response) {
+        return fooService.doSomethingSlow();
+    }
+}

sentinel-demo/sentinel-demo-spring-webflux/src/main/java/com/alibaba/csp/sentinel/demo/spring/webflux/service/BazService.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 1999-2019 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
+ *
+ *      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 com.alibaba.csp.sentinel.demo.spring.webflux.service;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.redis.core.ReactiveRedisTemplate;
+import org.springframework.stereotype.Service;
+import reactor.core.publisher.Mono;
+
+/**
+ * <p>A sample service for interacting with Redis via reactive Redis client.</p>
+ * <p>To play this service, you need a Redis instance running in local.</p>
+ *
+ * @author Eric Zhao
+ */
+@Service
+public class BazService {
+
+    @Autowired
+    private ReactiveRedisTemplate<String, String> template;
+
+    public Mono<String> getById(Long id) {
+        if (id == null || id <= 0) {
+            return Mono.error(new IllegalArgumentException("invalid id: " + id));
+        }
+        return template.opsForValue()
+            .get(KEY_PREFIX + id)
+            .switchIfEmpty(Mono.just("not_found"));
+    }
+
+    public Mono<Boolean> setValue(Long id, String value) {
+        if (id == null || id <= 0 || value == null) {
+            return Mono.error(new IllegalArgumentException("invalid parameters"));
+        }
+        return template.opsForValue()
+            .set(KEY_PREFIX + id, value);
+    }
+
+    private static final String KEY_PREFIX = "sentinel-reactor-test:";
+}

sentinel-demo/sentinel-demo-spring-webflux/src/main/java/com/alibaba/csp/sentinel/demo/spring/webflux/service/FooService.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright 1999-2018 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
+ *
+ *      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 com.alibaba.csp.sentinel.demo.spring.webflux.service;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadLocalRandom;
+
+import org.springframework.stereotype.Service;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+import reactor.core.scheduler.Scheduler;
+import reactor.core.scheduler.Schedulers;
+
+/**
+ * @author Eric Zhao
+ */
+@Service
+public class FooService {
+
+    private final ExecutorService pool = Executors.newFixedThreadPool(8);
+    private final Scheduler scheduler = Schedulers.fromExecutor(pool);
+
+    public Mono<String> emitSingle() {
+        return Mono.just(ThreadLocalRandom.current().nextInt(0, 2000))
+            .map(e -> e + "d");
+    }
+
+    public Flux<Integer> emitMultiple() {
+        int start = ThreadLocalRandom.current().nextInt(0, 6000);
+        return Flux.range(start, 10);
+    }
+
+    public Mono<String> doSomethingSlow() {
+        return Mono.fromCallable(() -> {
+            Thread.sleep(2000);
+            System.out.println("doSomethingSlow: " + Thread.currentThread().getName());
+            return "ok";
+        }).publishOn(scheduler);
+    }
+}

sentinel-demo/sentinel-demo-spring-webflux/src/main/resources/application.properties

@@ -0,0 +1,2 @@
+spring.application.name=sentinel-webflux-demo-application
+server.port=8081