To add Gateway demo

spring-cloud-alibaba-examples/spring-cloud-alibaba-dubbo-examples/pom.xml

@@ -20,6 +20,7 @@
         <module>spring-cloud-dubbo-provider-sample</module>
         <module>spring-cloud-dubbo-consumer-sample</module>
         <module>spring-cloud-dubbo-provider-web-sample</module>
+        <module>spring-cloud-dubbo-servlet-gateway-sample</module>
     </modules>
 
     <properties>

spring-cloud-alibaba-examples/spring-cloud-alibaba-dubbo-examples/spring-cloud-dubbo-servlet-gateway-sample/pom.xml

@@ -0,0 +1,39 @@
+<?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>spring-cloud-alibaba-dubbo-examples</artifactId>
+        <groupId>org.springframework.cloud</groupId>
+        <version>0.2.2.BUILD-SNAPSHOT</version>
+        <relativePath>../pom.xml</relativePath>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>org.springframework.cloud</groupId>
+    <artifactId>spring-cloud-dubbo-servlet-gateway-sample</artifactId>
+    <name>Spring Cloud Dubbo Servlet Gateway Sample</name>
+
+    <dependencies>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+
+        <!-- Sample API -->
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-dubbo-sample-api</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+
+        <!-- Spring Cloud Open Feign -->
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-starter-openfeign</artifactId>
+        </dependency>
+
+    </dependencies>
+
+</project>

spring-cloud-alibaba-examples/spring-cloud-alibaba-dubbo-examples/spring-cloud-dubbo-servlet-gateway-sample/src/main/java/org/springframework/cloud/alibaba/dubbo/bootstrap/DubboSpringCloudServletGatewayBootstrap.java

@@ -0,0 +1,23 @@
+package org.springframework.cloud.alibaba.dubbo.bootstrap;
+
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.boot.web.servlet.ServletComponentScan;
+import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
+import org.springframework.cloud.openfeign.EnableFeignClients;
+
+/**
+ * Dubbo Spring Cloud Servlet Gateway Bootstrap
+ */
+@EnableDiscoveryClient
+@EnableAutoConfiguration
+@EnableFeignClients
+@ServletComponentScan(basePackages = "org.springframework.cloud.alibaba.dubbo.gateway")
+public class DubboSpringCloudServletGatewayBootstrap {
+
+    public static void main(String[] args) {
+        new SpringApplicationBuilder(DubboSpringCloudServletGatewayBootstrap.class)
+                .properties("spring.profiles.active=nacos")
+                .run(args);
+    }
+}

spring-cloud-alibaba-examples/spring-cloud-alibaba-dubbo-examples/spring-cloud-dubbo-servlet-gateway-sample/src/main/java/org/springframework/cloud/alibaba/dubbo/gateway/DubboGatewayServlet.java

@@ -0,0 +1,188 @@
+package org.springframework.cloud.alibaba.dubbo.gateway;
+
+import org.apache.commons.lang.StringUtils;
+import org.apache.dubbo.rpc.service.GenericException;
+import org.apache.dubbo.rpc.service.GenericService;
+import org.springframework.cloud.alibaba.dubbo.http.MutableHttpServerRequest;
+import org.springframework.cloud.alibaba.dubbo.metadata.DubboServiceMetadata;
+import org.springframework.cloud.alibaba.dubbo.metadata.DubboTransportedMetadata;
+import org.springframework.cloud.alibaba.dubbo.metadata.RequestMetadata;
+import org.springframework.cloud.alibaba.dubbo.metadata.RestMethodMetadata;
+import org.springframework.cloud.alibaba.dubbo.metadata.repository.DubboServiceMetadataRepository;
+import org.springframework.cloud.alibaba.dubbo.service.DubboGenericServiceExecutionContext;
+import org.springframework.cloud.alibaba.dubbo.service.DubboGenericServiceExecutionContextFactory;
+import org.springframework.cloud.alibaba.dubbo.service.DubboGenericServiceFactory;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpRequest;
+import org.springframework.util.AntPathMatcher;
+import org.springframework.util.CollectionUtils;
+import org.springframework.util.PathMatcher;
+import org.springframework.util.StreamUtils;
+import org.springframework.web.util.UriComponents;
+
+import javax.servlet.ServletException;
+import javax.servlet.ServletInputStream;
+import javax.servlet.annotation.WebServlet;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.*;
+
+import static org.springframework.web.util.UriComponentsBuilder.fromUriString;
+
+@WebServlet(urlPatterns = "/dsc/*")
+public class DubboGatewayServlet extends HttpServlet {
+
+    private final DubboServiceMetadataRepository repository;
+
+    private final DubboTransportedMetadata dubboTransportedMetadata;
+
+    private final DubboGenericServiceFactory serviceFactory;
+
+    private final DubboGenericServiceExecutionContextFactory contextFactory;
+
+    private final PathMatcher pathMatcher = new AntPathMatcher();
+
+    public DubboGatewayServlet(DubboServiceMetadataRepository repository,
+                               DubboGenericServiceFactory serviceFactory,
+                               DubboGenericServiceExecutionContextFactory contextFactory) {
+        this.repository = repository;
+        this.dubboTransportedMetadata = new DubboTransportedMetadata();
+        dubboTransportedMetadata.setProtocol("dubbo");
+        dubboTransportedMetadata.setCluster("failover");
+        this.serviceFactory = serviceFactory;
+        this.contextFactory = contextFactory;
+    }
+
+    public void service(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
+
+        // /g/{app-name}/{rest-path}
+        String requestURI = request.getRequestURI();
+        // /g/
+        String servletPath = request.getServletPath();
+
+        String part = StringUtils.substringAfter(requestURI, servletPath);
+
+        String serviceName = StringUtils.substringBetween(part, "/", "/");
+
+        // App name= spring-cloud-alibaba-dubbo-web-provider (127.0.0.1:8080)
+
+        String restPath = StringUtils.substringAfter(part, serviceName);
+
+        // 初始化 serviceName 的 REST 请求元数据
+        repository.initialize(serviceName);
+        // 将 HttpServletRequest 转化为 RequestMetadata
+        RequestMetadata clientMetadata = buildRequestMetadata(request, restPath);
+
+        DubboServiceMetadata dubboServiceMetadata = repository.get(serviceName, clientMetadata);
+
+        if (dubboServiceMetadata == null) {
+            // if DubboServiceMetadata is not found, executes next
+            throw new ServletException("DubboServiceMetadata can't be found!");
+        }
+
+        RestMethodMetadata dubboRestMethodMetadata = dubboServiceMetadata.getRestMethodMetadata();
+
+        GenericService genericService = serviceFactory.create(dubboServiceMetadata, dubboTransportedMetadata);
+
+        // TODO: Get the Request Body from HttpServletRequest
+        byte[] body = getRequestBody(request);
+
+        MutableHttpServerRequest httpServerRequest = new MutableHttpServerRequest(new HttpRequestAdapter(request), body);
+
+//        customizeRequest(httpServerRequest, dubboRestMethodMetadata, clientMetadata);
+
+        DubboGenericServiceExecutionContext context = contextFactory.create(dubboRestMethodMetadata, httpServerRequest);
+
+        Object result = null;
+        GenericException exception = null;
+
+        try {
+            result = genericService.$invoke(context.getMethodName(), context.getParameterTypes(), context.getParameters());
+        } catch (GenericException e) {
+            exception = e;
+        }
+        response.getWriter().println(result);
+    }
+
+    private byte[] getRequestBody(HttpServletRequest request) throws IOException {
+        ServletInputStream inputStream = request.getInputStream();
+        return StreamUtils.copyToByteArray(inputStream);
+    }
+
+    private static class HttpRequestAdapter implements HttpRequest {
+
+        private final HttpServletRequest request;
+
+        private HttpRequestAdapter(HttpServletRequest request) {
+            this.request = request;
+        }
+
+        @Override
+        public String getMethodValue() {
+            return request.getMethod();
+        }
+
+        @Override
+        public URI getURI() {
+            try {
+                return new URI(request.getRequestURL().toString() + "?" + request.getQueryString());
+            } catch (URISyntaxException e) {
+                e.printStackTrace();
+            }
+            throw new RuntimeException();
+        }
+
+        @Override
+        public HttpHeaders getHeaders() {
+            return new HttpHeaders();
+        }
+    }
+
+//    protected void customizeRequest(MutableHttpServerRequest httpServerRequest,
+//                                    RestMethodMetadata dubboRestMethodMetadata, RequestMetadata clientMetadata) {
+//
+//        RequestMetadata dubboRequestMetadata = dubboRestMethodMetadata.getRequest();
+//        String pathPattern = dubboRequestMetadata.getPath();
+//
+//        Map<String, String> pathVariables = pathMatcher.extractUriTemplateVariables(pathPattern, httpServerRequest.getPath());
+//
+//        if (!CollectionUtils.isEmpty(pathVariables)) {
+//            // Put path variables Map into query parameters Map
+//            httpServerRequest.params(pathVariables);
+//        }
+//
+//    }
+
+    private RequestMetadata buildRequestMetadata(HttpServletRequest request, String restPath) {
+        UriComponents uriComponents = fromUriString(request.getRequestURI()).build(true);
+        RequestMetadata requestMetadata = new RequestMetadata();
+        requestMetadata.setPath(restPath);
+        requestMetadata.setMethod(request.getMethod());
+        requestMetadata.setParams(getParams(request));
+        requestMetadata.setHeaders(getHeaders(request));
+        return requestMetadata;
+    }
+
+    private Map<String, List<String>> getHeaders(HttpServletRequest request) {
+        Map<String, List<String>> map = new LinkedHashMap<>();
+        Enumeration<String> headerNames = request.getHeaderNames();
+        while (headerNames.hasMoreElements()) {
+            String headerName = headerNames.nextElement();
+            Enumeration<String> headerValues = request.getHeaders(headerName);
+            map.put(headerName, Collections.list(headerValues));
+        }
+        return map;
+    }
+
+    private Map<String, List<String>> getParams(HttpServletRequest request) {
+        Map<String, List<String>> map = new LinkedHashMap<>();
+        for (Map.Entry<String, String[]> entry : request.getParameterMap().entrySet()) {
+            map.put(entry.getKey(), Arrays.asList(entry.getValue()));
+        }
+        return map;
+    }
+}

spring-cloud-alibaba-examples/spring-cloud-alibaba-dubbo-examples/spring-cloud-dubbo-servlet-gateway-sample/src/main/resources/application.yaml

@@ -0,0 +1,12 @@
+dubbo:
+  registry:
+    #   The Spring Cloud Dubbo's registry extension
+    address: spring-cloud://localhost
+#   The traditional Dubbo's registry
+#   address: zookeeper://127.0.0.1:2181
+server:
+  port: 0
+
+provider:
+  application:
+    name: spring-cloud-alibaba-dubbo-web-provider

spring-cloud-alibaba-examples/spring-cloud-alibaba-dubbo-examples/spring-cloud-dubbo-servlet-gateway-sample/src/main/resources/bootstrap.yaml

@@ -0,0 +1,70 @@
+spring:
+  application:
+    name: spring-cloud-alibaba-dubbo-servlet-gateway
+  main:
+    allow-bean-definition-overriding: true
+
+
+  # default disable all
+  cloud:
+    nacos:
+      discovery:
+        enabled: false
+        register-enabled: false
+    zookeeper:
+      enabled: false
+    consul:
+      enabled: false
+
+eureka:
+  client:
+    enabled: false
+
+ribbon:
+  nacos:
+    enabled: false
+
+---
+spring:
+  profiles: nacos
+
+  cloud:
+    nacos:
+      discovery:
+        enabled: true
+        register-enabled: true
+        server-addr: 127.0.0.1:8848
+
+ribbon:
+  nacos:
+    enabled: true
+
+---
+spring:
+  profiles: eureka
+
+eureka:
+  client:
+    enabled: true
+    service-url:
+      defaultZone: http://127.0.0.1:8761/eureka/
+
+
+---
+spring:
+  profiles: zookeeper
+  cloud:
+    zookeeper:
+      enabled: true
+      connect-string: 127.0.0.1:2181
+
+
+---
+spring:
+  profiles: consul
+
+  cloud:
+    consul:
+      enabled: true
+      host: 127.0.0.1
+      port: 8500