Add gateway adapter for Zuul 2.x (#1138)

- also add demo for Zuul 2.x adapter

sentinel-adapter/pom.xml

@@ -26,6 +26,7 @@
         <module>sentinel-api-gateway-adapter-common</module>
         <module>sentinel-spring-cloud-gateway-adapter</module>
         <module>sentinel-spring-webmvc-adapter</module>
+        <module>sentinel-zuul2-adapter</module>
     </modules>
 
     <dependencyManagement>

sentinel-adapter/sentinel-zuul2-adapter/README.md

@@ -0,0 +1,101 @@
+# Sentinel Zuul 2.x Adapter
+
+This adapter provides **route level** and **customized API level**
+flow control for Zuul 2.x API Gateway.
+
+> *Note*: this adapter only support Zuul 2.x.
+
+## How to use
+
+> You can refer to demo `sentinel-demo-zuul2-gateway`
+
+1. Add Maven dependency to your `pom.xml`:
+
+```xml
+<dependency>
+    <groupId>com.alibaba.csp</groupId>
+    <artifactId>sentinel-zuul2-adapter</artifactId>
+    <version>x.y.z</version>
+</dependency>
+```
+
+2. Register filters
+
+```java
+filterMultibinder.addBinding().toInstance(new SentinelZuulInboundFilter(500));
+filterMultibinder.addBinding().toInstance(new SentinelZuulOutboundFilter(500));
+filterMultibinder.addBinding().toInstance(new SentinelZuulEndpoint());
+```
+
+## How it works
+
+As Zuul 2.x is based on netty, a event-drive model, so we use `AsyncEntry` to do flow control.
+
+- `SentinelZuulInboundFilter`: This inbound filter will regard all proxy ID (`proxy` in `SessionContext`) and all customized API as resources. When a `BlockException` caught, the filter will set endpoint to find a fallback to execute.
+- `SentinelZuulOutboundFilter`: When the response has no exception caught, the post filter will trace the exception and complete the entries.
+- `SentinelZuulEndpoint`: When an exception is caught, the filter will find a fallback to execute.
+
+## Integration with Sentinel Dashboard
+
+1. Start [Sentinel Dashboard](https://github.com/alibaba/Sentinel/wiki/Dashboard).
+2. You can configure the rules in Sentinel dashboard or via dynamic rule configuration.
+
+## Fallbacks
+
+You can implement `ZuulBlockFallbackProvider` to define your own fallback provider when Sentinel `BlockException` is thrown.
+The default fallback provider is `DefaultBlockFallbackProvider`.
+
+By default fallback route is proxy ID (or customized API name).
+
+Here is an example:
+
+```java
+
+// custom provider
+public class MyBlockFallbackProvider implements ZuulBlockFallbackProvider {
+
+    private Logger logger = LoggerFactory.getLogger(DefaultBlockFallbackProvider.class);
+
+    // you can define root as service level
+    @Override
+    public String getRoute() {
+        return "my-route";
+    }
+
+    @Override
+        public BlockResponse fallbackResponse(String route, Throwable cause) {
+            RecordLog.info(String.format("[Sentinel DefaultBlockFallbackProvider] Run fallback route: %s", route));
+            if (cause instanceof BlockException) {
+                return new BlockResponse(429, "Sentinel block exception", route);
+            } else {
+                return new BlockResponse(500, "System Error", route);
+            }
+        }
+ }
+
+ // register fallback
+ ZuulBlockFallbackManager.registerProvider(new MyBlockFallbackProvider());
+```
+
+Default block response:
+
+```json
+{
+    "code":429,
+    "message":"Sentinel block exception",
+    "route":"/"
+}
+```
+
+## Request origin parser
+
+You can register customized request origin parser like this:
+
+```java
+public class MyRequestOriginParser implements RequestOriginParser {
+    @Override
+    public String parseOrigin(HttpRequestMessage request) {
+        return request.getInboundRequest().getOriginalHost() + ":" + request.getInboundRequest().getOriginalPort();
+    }
+}
+```

sentinel-adapter/sentinel-zuul2-adapter/pom.xml

@@ -0,0 +1,62 @@
+<?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-adapter</artifactId>
+        <groupId>com.alibaba.csp</groupId>
+        <version>1.7.2-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>sentinel-zuul2-adapter</artifactId>
+    <packaging>jar</packaging>
+
+    <properties>
+        <java.source.version>1.8</java.source.version>
+        <java.target.version>1.8</java.target.version>
+        <zuul.version>2.1.5</zuul.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.alibaba.csp</groupId>
+            <artifactId>sentinel-core</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.alibaba.csp</groupId>
+            <artifactId>sentinel-api-gateway-adapter-common</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>com.netflix.zuul</groupId>
+            <artifactId>zuul-core</artifactId>
+            <version>${zuul.version}</version>
+            <scope>provided</scope>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.mockito</groupId>
+                    <artifactId>mockito-core</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-core</artifactId>
+            <version>5.1.9.RELEASE</version>
+        </dependency>
+
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+</project>

sentinel-adapter/sentinel-zuul2-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/gateway/zuul2/HttpRequestMessageItemParser.java

@@ -0,0 +1,32 @@
+package com.alibaba.csp.sentinel.adapter.gateway.zuul2;
+
+import com.alibaba.csp.sentinel.adapter.gateway.common.param.RequestItemParser;
+import com.netflix.zuul.message.http.HttpRequestMessage;
+
+public class HttpRequestMessageItemParser implements RequestItemParser<HttpRequestMessage> {
+
+    @Override
+    public String getPath(HttpRequestMessage request) {
+        return request.getInboundRequest().getPath();
+    }
+
+    @Override
+    public String getRemoteAddress(HttpRequestMessage request) {
+        return request.getOriginalHost();
+    }
+
+    @Override
+    public String getHeader(HttpRequestMessage request, String key) {
+        return String.valueOf(request.getInboundRequest().getHeaders().get(key));
+    }
+
+    @Override
+    public String getUrlParam(HttpRequestMessage request, String paramName) {
+        return String.valueOf(request.getInboundRequest().getQueryParams().get(paramName));
+    }
+
+    @Override
+    public String getCookieValue(HttpRequestMessage request, String cookieName) {
+        return String.valueOf(request.getInboundRequest().parseCookies().get(cookieName));
+    }
+}

sentinel-adapter/sentinel-zuul2-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/gateway/zuul2/api/ZuulApiDefinitionChangeObserver.java

@@ -0,0 +1,33 @@
+/*
+ * 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
+ *
+ *      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.adapter.gateway.zuul2.api;
+
+import java.util.Set;
+
+import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiDefinition;
+import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiDefinitionChangeObserver;
+
+/**
+ * @author Eric Zhao
+ * @since 1.6.0
+ */
+public class ZuulApiDefinitionChangeObserver implements ApiDefinitionChangeObserver {
+
+    @Override
+    public void onChange(Set<ApiDefinition> apiDefinitions) {
+        ZuulGatewayApiMatcherManager.loadApiDefinitions(apiDefinitions);
+    }
+}

sentinel-adapter/sentinel-zuul2-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/gateway/zuul2/api/ZuulGatewayApiMatcherManager.java

@@ -0,0 +1,68 @@
+/*
+ * 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
+ *
+ *      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.adapter.gateway.zuul2.api;
+
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiDefinition;
+import com.alibaba.csp.sentinel.adapter.gateway.zuul2.api.matcher.HttpRequestMessageApiMatcher;
+
+/**
+ * @author wavesZh
+ */
+public final class ZuulGatewayApiMatcherManager {
+
+    private static final Map<String, HttpRequestMessageApiMatcher> API_MATCHER_MAP = new ConcurrentHashMap<>();
+
+    public static Map<String, HttpRequestMessageApiMatcher> getApiMatcherMap() {
+        return Collections.unmodifiableMap(API_MATCHER_MAP);
+    }
+
+    public static HttpRequestMessageApiMatcher getMatcher(final String apiName) {
+        if (apiName == null) {
+            return null;
+        }
+        return API_MATCHER_MAP.get(apiName);
+    }
+
+    public static Set<ApiDefinition> getApiDefinitionSet() {
+        Set<ApiDefinition> set = new HashSet<>();
+        for (HttpRequestMessageApiMatcher matcher : API_MATCHER_MAP.values()) {
+            set.add(matcher.getApiDefinition());
+        }
+        return set;
+    }
+
+    static synchronized void loadApiDefinitions(/*@Valid*/ Set<ApiDefinition> definitions) {
+        if (definitions == null || definitions.isEmpty()) {
+            API_MATCHER_MAP.clear();
+            return;
+        }
+        for (ApiDefinition definition : definitions) {
+            addApiDefinition(definition);
+        }
+    }
+
+    static void addApiDefinition(ApiDefinition definition) {
+        API_MATCHER_MAP.put(definition.getApiName(), new HttpRequestMessageApiMatcher(definition));
+    }
+
+    private ZuulGatewayApiMatcherManager() {}
+}

sentinel-adapter/sentinel-zuul2-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/gateway/zuul2/api/matcher/HttpRequestMessageApiMatcher.java

@@ -0,0 +1,70 @@
+/*
+ * 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
+ *
+ *      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.adapter.gateway.zuul2.api.matcher;
+
+import com.alibaba.csp.sentinel.adapter.gateway.common.SentinelGatewayConstants;
+import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiDefinition;
+import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiPathPredicateItem;
+import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiPredicateItem;
+import com.alibaba.csp.sentinel.adapter.gateway.common.api.matcher.AbstractApiMatcher;
+import com.alibaba.csp.sentinel.adapter.gateway.zuul2.api.route.ZuulRouteMatchers;
+import com.alibaba.csp.sentinel.util.StringUtil;
+import com.alibaba.csp.sentinel.util.function.Predicate;
+import com.netflix.zuul.message.http.HttpRequestMessage;
+
+/**
+ * @author wavesZh
+ */
+public class HttpRequestMessageApiMatcher extends AbstractApiMatcher<HttpRequestMessage> {
+
+    public HttpRequestMessageApiMatcher(ApiDefinition apiDefinition) {
+        super(apiDefinition);
+    }
+
+    @Override
+    protected void initializeMatchers() {
+        if (apiDefinition.getPredicateItems() != null) {
+            for (ApiPredicateItem item : apiDefinition.getPredicateItems()) {
+                Predicate<HttpRequestMessage> predicate = fromApiPredicate(item);
+                if (predicate != null) {
+                    matchers.add(predicate);
+                }
+            }
+        }
+    }
+
+    private Predicate<HttpRequestMessage> fromApiPredicate(/*@NonNull*/ ApiPredicateItem item) {
+        if (item instanceof ApiPathPredicateItem) {
+            return fromApiPathPredicate((ApiPathPredicateItem)item);
+        }
+        return null;
+    }
+
+    private Predicate<HttpRequestMessage> fromApiPathPredicate(/*@Valid*/ ApiPathPredicateItem item) {
+        String pattern = item.getPattern();
+        if (StringUtil.isBlank(pattern)) {
+            return null;
+        }
+        switch (item.getMatchStrategy()) {
+            case SentinelGatewayConstants.URL_MATCH_STRATEGY_REGEX:
+                return ZuulRouteMatchers.regexPath(pattern);
+            case SentinelGatewayConstants.URL_MATCH_STRATEGY_PREFIX:
+                return ZuulRouteMatchers.antPath(pattern);
+            default:
+                return ZuulRouteMatchers.exactPath(pattern);
+        }
+    }
+}