Spring Cloud是一系列框架的有序集合。它利用Spring Boot的開發便利性巧妙地簡化了分布式系統基礎設施的開發,如服務發現注冊、配置中心、消息總線、負載均衡、斷路器、數據監控等,都可以用Spring Boot的開發風格做到一鍵啟動和部署。Spring并沒有重復制造輪子,它只是將目前各家公司開發的比較成熟、經得起實際考驗的服務框架組合起來,通過Spring Boot風格進行再封裝屏蔽掉了復雜的配置和實現原理,最終給開發者留出了一套簡單易懂、易部署和易維護的分布式系統開發工具包。
接下來我們就使用SpringCloud實現一套簡單的微服務架構。
以下所有代碼都已開源到github上了,地址:https://github.com/lynnlovemin/softservice
Eureka(服務注冊與發現)
首先引入相關的依賴包
<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-eureka</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-eureka-server</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>Dalston.RC1</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories>
配置application.yml
server: port: 8761eureka: instance: hostname: localhost client: registerWithEureka: false fetchRegistry: false serviceUrl: defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/
創建啟動類Application
@EnableEurekaServer@SpringBootApplicationpublic class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); }}
運行main方法,瀏覽器訪問:http://localhost:8761,我們就能在瀏覽器看到如下界面:
說明eureka啟動成功。
接下來,我們實現負債均衡、斷路器、網關、客戶端,所有的服務都應該注冊到eureka中,并且訪問eureka就能看到所有注冊的服務
client(客戶端)
pom.xml
<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-eureka</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>Dalston.RC1</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories>
application.yml
eureka: client: serviceUrl: defaultZone: http://localhost:8761/eureka/ #這里注冊到eureka中server: port: 8763spring: application: name: service-hi
Application類
@SpringBootApplication@EnableEurekaClient@RestControllerpublic class Application { public static void main(String[] args) { SpringApplication.run(Applicatioin.class, args); } @Value("${server.port}") String port; //這里我們提供一個接口 @RequestMapping("/hi") public String home(@RequestParam String name) { return "hi "+name+",i am from port:" +port; }}
Feign(負債均衡、斷路器)
pom.xml
<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-eureka</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-feign</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-hystrix-dashboard</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>Dalston.RC1</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories>
application.yml
eureka: client: serviceUrl: defaultZone: http://localhost:8761/eureka/server: port: 8765spring: application: name: service-feignfeign: hystrix: enabled: true
Application類
@SpringBootApplication@EnableDiscoveryClient@EnableFeignClients@EnableHystrixDashboardpublic class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); }}
然后再提供一個service,他的作用就是做負債均衡和斷路器功能
@FeignClient(value = "service-hi",fallback = SchedualServiceHiHystric.class)public interface SchedualServiceHi { @RequestMapping(value = "/hi",method = RequestMethod.GET) String sayHiFromClientOne(@RequestParam(value = "name") String name);}
@Componentpublic class SchedualServiceHiHystric implements SchedualServiceHi { @Override public String sayHiFromClientOne(String name) { return "sorry "+name; }}
FeignClient我們指定之前創建client時指定的name:service-hi,fallback指定服務不可用時的返回數據,這樣我們啟動多個client時就可以看到http請求時會交替訪問不同的feign端口,當停掉clien時再訪問接口會返回錯誤信息。
zuul(服務網關)
在一般情況下,我們不會直接暴露客戶端給外部,而是通過服務網關來轉發,內部服務都是在局域網內通信,外部訪問不了,通過服務網關,我們還可以統一做接口的安全性校驗,統一攔截,請看代碼:
pom.xml
<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-eureka</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-zuul</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>Dalston.RC1</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </repository>
application.yml
eureka: client: serviceUrl: defaultZone: http://localhost:8761/eureka/server: port: 8080spring: application: name: service-zuulzuul: routes: api-b: path: /api/** serviceId: service-feign #凡是以api開始的請求都訪問service-feign服務
Application類
@EnableZuulProxy@EnableEurekaClient@SpringBootApplicationpublic class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); }}
啟動Application,訪問:http://localhost:8080/api/hi,就能訪問到之前我們定義的接口,接下來我們做接口的攔截:
/** * filterType:返回一個字符串代表過濾器的類型,在zuul中定義了四種不同生命周期的過濾器類型,具體如下: pre:路由之前 routing:路由之時 post: 路由之后 error:發送錯誤調用 filterOrder:過濾的順序 shouldFilter:這里可以寫邏輯判斷,是否要過濾,本文true,永遠過濾。 run:過濾器的具體邏輯??捎煤軓碗s,包括查sql,nosql去判斷該請求到底有沒有權限訪問。 */@Componentpublic class MyFilter extends ZuulFilter{ private static Logger log = LoggerFactory.getLogger(MyFilter.class); @Override public String filterType() { return "pre"; } @Override public int filterOrder() { return 0; } @Override public boolean shouldFilter() { return true; } @Override public Object run() { RequestContext ctx = RequestContext.getCurrentContext(); HttpServletRequest request = ctx.getRequest(); log.info(String.format("%s >>> %s", request.getMethod(), request.getRequestURL().toString())); Object accessToken = request.getParameter("token"); if(accessToken == null) { log.warn("token is empty"); ctx.setSendZuulResponse(false); ctx.setResponseStatusCode(401); try { ctx.getResponse().getWriter().write("token is empty"); }catch (Exception e){} return null; } log.info("ok"); return null; }}
這樣我們在調用接口前會先執行MyFilter類中的run方法,在這個方法里可以做一系列安全驗證,比如token。
好了,一個簡單的微服務架構就已經搭建完成了。
以上所有代碼都已開源到github上了,地址:https://github.com/lynnlovemin/softservice
以上所述是小編給大家介紹的SpringCloud實現簡單的微服務架構,希望對大家有所幫助,如果大家有任何疑問請給我留言,小編會及時回復
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