从零搭建Spring Cloud Gateway网关（一）

# 新建Spring Boot项目 怎么新建Spring Boot项目这里不再具体赘述，不会的可以翻看下之前的博客或者直接百度。这里直接贴出对应的pom文件。 pom依赖如下： ```xml 4.0.0 org.springframework.boot spring-boot-starter-parent 2.2.5.RELEASE com.lifengdi gateway 0.0.1-SNAPSHOT gateway Demo project for Spring Boot 1.8 Hoxton.SR3 org.springframework.cloud spring-cloud-starter-gateway org.projectlombok lombok 1.18.12 true org.springframework.boot spring-boot-starter-test test org.junit.vintage junit-vintage-engine org.springframework.cloud spring-cloud-starter-netflix-hystrix org.springframework.boot spring-boot-starter-actuator org.apache.commons commons-pool2 commons-io commons-io 2.5 compile com.alibaba fastjson 1.2.58 org.springframework.boot spring-boot-starter-mail org.springframework.cloud spring-cloud-dependencies ${spring-cloud.version} pom import org.springframework.boot spring-boot-maven-plugin ``` 由于是网关项目，所以不需要`spring-boot-starter-web`相关的依赖。 配置文件如下： ```yaml server: port: 8080 spring: application: name: spring-cloud-gateway-demo cloud: gateway: discovery: locator: enabled: true #启用路由访问 routes: - id: path_route # 指定域名 uri: http://localhost:8081 predicates: - Path=/jar/** filters: # 熔断配置 - name: Hystrix args: name: default fallbackUri: forward:/fallback - id: path_route2 # 指定域名 uri: http://localhost:8082 predicates: - Path=/war/** filters: # 熔断配置 - name: Hystrix args: name: hystrix1 fallbackUri: forward:/fallback mvc: throw-exception-if-no-handler-found: true # 默认熔断超时时间30s hystrix: command: default: execution: isolation: thread: timeoutInMilliseconds: 3000 hystrix1: execution: isolation: thread: timeoutInMilliseconds: 1000 ``` # 熔断（接口或者项目） 熔断相关jar包如下： ```xml org.springframework.cloud spring-cloud-starter-netflix-hystrix ``` 默认的熔断回调接口： ```java package com.lifengdi.gateway.hystrix; import com.lifengdi.gateway.exception.BaseException; import com.lifengdi.gateway.response.ResponseResult; import lombok.extern.slf4j.Slf4j; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; /** * @author: Li Fengdi * @date: 2020-03-18 16:35 */ @RestController @Slf4j public class DefaultHystrixController { @RequestMapping("/fallback") public ResponseResult fallback(){ log.error("触发熔断......"); return ResponseResult.fail(BaseException.DEFAULT_HYSTRIX.build()); } } ``` 具体配置文件说明如下： ```yaml routes: - id: path_route # 指定域名 uri: http://localhost:8081 predicates: - Path=/jar/** filters: # 熔断配置 - name: Hystrix args: name: default fallbackUri: forward:/fallback - id: path_route2 # 指定域名 uri: http://localhost:8082 predicates: - Path=/war/** filters: # 熔断配置 - name: Hystrix args: name: hystrix1 fallbackUri: forward:/fallback mvc: throw-exception-if-no-handler-found: true # 默认熔断超时时间30s hystrix: command: default: execution: isolation: thread: timeoutInMilliseconds: 3000 hystrix1: execution: isolation: thread: timeoutInMilliseconds: 1000 ``` `default`、`hystrix1`为自定义的参数，可以配置多个熔断策略，不同的接口、服务可以单独配置对应的超时时间，不需要额外的进行开发，不过需要增加额外的配置文件。 # 全局session共享 依赖jar包： ```xml org.springframework.boot spring-boot-starter-data-redis-reactive org.springframework.session spring-session-data-redis org.apache.commons commons-pool2 org.springframework.boot spring-boot-starter-security ``` 相关yml配置： ```yaml spring: redis: database: 0 host: localhost port: 6379 password: 123456 lettuce: pool: max-active: 300 max-idle: 8 max-wait: -1ms min-idle: 0 session: store-type: redis ``` `spring.session.store-type`Spring默认就是redis实现的，也有其他的，配置不同罢了。 增加代码如下： 权限相关，这里默认全部放行： ```java package com.lifengdi.gateway.config; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.security.config.annotation.web.reactive.EnableWebFluxSecurity; import org.springframework.security.config.web.server.ServerHttpSecurity; import org.springframework.security.web.server.SecurityWebFilterChain; @Configuration @EnableWebFluxSecurity public class GatewaySecurityConfig { @Bean SecurityWebFilterChain springWebFilterChain(ServerHttpSecurity serverHttpSecurity) throws Exception { serverHttpSecurity .csrf().disable() .authorizeExchange().pathMatchers("/**").permitAll() .anyExchange() .authenticated(); return serverHttpSecurity.build(); } } ``` session相关： ```java package com.lifengdi.gateway.config; import com.lifengdi.gateway.resolver.MyCookieWebSessionIdResolver; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.http.ResponseCookie; import org.springframework.session.data.redis.config.annotation.web.server.EnableRedisWebSession; import org.springframework.web.server.session.CookieWebSessionIdResolver; import org.springframework.web.server.session.WebSessionIdResolver; import java.util.function.Consumer; @Configuration @EnableRedisWebSession(maxInactiveIntervalInSeconds = 10*60*60, redisNamespace = "my:spring:session") public class WebSessionConfig { @Bean public WebSessionIdResolver webSessionIdResolver() { CookieWebSessionIdResolver resolver = new MyCookieWebSessionIdResolver(); resolver.setCookieName("SESSIONID"); Consumer consumer = responseCookieBuilder -> { responseCookieBuilder.path("/"); }; resolver.addCookieInitializer(consumer); return resolver; } } ``` 注意这里使用的是`@EnableRedisWebSession`注解，而不是`@EnableRedisHttpSession`，这个是和zuul不一样的地方。 用zuul做网关的时候，直接使用`@EnableRedisHttpSession`在配置里面就可以通过redis共享session信息 Spring同时提供了`@EnableRedisWebSession`来对WebFlux的支持。 值得一提的是这两个注解内部实现并不相同，需要自定义的配置也不一样。 这里自定义cookieName、path等是自定义了`webSessionIdResolver`来实现的，而不是`cookieSerializer`。如果使用`cookieSerializer`的话，对`@EnableRedisWebSession`来说是不起作用的。这个坑之前坑了好半天！ MyCookieWebSessionIdResolver代码如下： ```java package com.lifengdi.gateway.resolver; import lombok.extern.slf4j.Slf4j; import org.springframework.http.HttpCookie; import org.springframework.session.web.http.DefaultCookieSerializer; import org.springframework.util.MultiValueMap; import org.springframework.web.server.ServerWebExchange; import org.springframework.web.server.session.CookieWebSessionIdResolver; import java.util.Base64; import java.util.Collections; import java.util.List; import java.util.stream.Collectors; /** * 自定义WebSessionId解析器，以兼容{@link org.springframework.session.data.redis.config.annotation.web.http.EnableRedisHttpSession} *

* 使用EnableRedisHttpSession时{@link DefaultCookieSerializer}中useBase64Encoding默认为true，将cookie中的sessionId使用base64 * 加密，但是如果使用{@link org.springframework.session.data.redis.config.annotation.web.server.EnableRedisWebSession}，默认 * 的解析器没有将sessionId解密，导致获取不到正确的session *

* * @author: Li Fengdi * @date: 2020/3/16 15:41 */ @Slf4j public class MyCookieWebSessionIdResolver extends CookieWebSessionIdResolver { @Override public List resolveSessionIds(ServerWebExchange exchange) { MultiValueMap cookieMap = exchange.getRequest().getCookies(); List cookies = cookieMap.get(getCookieName()); if (cookies == null) { return Collections.emptyList(); } return cookies.stream().map(HttpCookie::getValue).map(this::base64Decode).collect(Collectors.toList()); } /** * base64解码 * * @param base64Value base64Value * @return 解码后的字符串 */ private String base64Decode(String base64Value) { try { byte[] decodedCookieBytes = Base64.getDecoder().decode(base64Value); return new String(decodedCookieBytes); } catch (Exception ex) { log.debug("Unable to Base64 decode value: " + base64Value); return null; } } } ``` 其实这段代码本就是参考了`cookieSerializer`中的代码来实现的。 > 如果指定了useBase64Encoding为false，即不加密sessionId，那么就不需要这一段代码了。 代码已上传到git上，需要的可以去看看。 git代码地址：[https://github.com/lifengdi/spring-cloud-gateway-demo](https://github.com/lifengdi/spring-cloud-gateway-demo) 原文地址：[https://www.lifengdi.com/archives/article/1776](https://www.lifengdi.com/archives/article/1776)