Spring Cloud 纯干货，从入门到实战

导读

　　之前写过一篇SpringCloud从入门到精通的点我直达，微服务基础知识点我直达，今天我们使用Spring Cloud模拟一个电商项目。分别有以下2个服务，商品、订单。下面我们开始叭

技术栈

1. SpringBoot整合SpringCloud
2. 通信方式：http restful
3. 注册中心：eruka
4. 断路器：hystrix
5. 网关：zuul

商品服务

功能点

• 商品列表
• 商品详情

订单服务

功能点

• 我的订单
• 下单接口

搭建Eureka Server

创建项目

项目结构

pom.xml

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.18.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ybchen</groupId>
    <artifactId>eureka_server</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>eureka_server</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR6</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</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>${spring-cloud.version}</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>

</project>

启动类上加注解

application.properties

# 服务端口号
server.port=8761
# eureka主机名
eureka.instance.hostname=localhost
# 指定当前主机是否需要向注册中心注册(不用，因为当前主机是Server，不是Client)
eureka.client.register-with-eureka=false
# 指定当前主机是否需要获取注册信息(不用，因为当前主机是Server，不是Client)
eureka.client.fetch-registry=false
# 注册中心地址
eureka.client.service-url.defaultZone=http://${eureka.instance.hostname}:${server.port}/eureka/

启动服务并查看监控台

搭建Eureka Client商品服务

创建项目

项目结构

pom.xml

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.18.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ybchen</groupId>
    <artifactId>product_service</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>product_service</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR6</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</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>${spring-cloud.version}</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>

</project>

application.properties

# 服务端口号
server.port=8771
# 服务名称
spring.application.name=product_service
# 将服务注册到注册中心，eureka_service的地址
eureka.client.service-url.defaultZone:http://localhost:8761/eureka/

ProductController.java

package com.ybchen.product_service.controller;

import com.ybchen.product_service.service.ProductService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

/**
 * @ClassName：ProductController
 * @Description：商品
 * @Author：chenyb
 * @Date：2020/11/1 8:42 下午
 * @Versiion：1.0
 */
@RestController
@RequestMapping("/api/v1/product")
public class ProductController {
    @Autowired
    private ProductService productService;

    /**
     * 商品列表
     *
     * @return
     */
    @PostMapping("list")
    public Object list() {
        return productService.listProduct();
    }

    /**
     * 根据id查询商品
     *
     * @param id
     * @return
     */
    @GetMapping("findById")
    public Object findById(@RequestParam("id") int id) {
        return productService.findById(id);
    }
}

Product.java

package com.ybchen.product_service.domain;

import java.io.Serializable;

/**
 * @ClassName：Product
 * @Description：商品实体类
 * @Author：chenyb
 * @Date：2020/11/1 8:43 下午
 * @Versiion：1.0
 */
public class Product implements Serializable {
    /**
     * 内码
     */
    private String id;
    /**
     * 商品名称
     */
    private String name;
    /**
     * 价格，分为单位
     */
    private int price;
    /**
     * 库存
     */
    private int store;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getPrice() {
        return price;
    }

    public void setPrice(int price) {
        this.price = price;
    }

    public int getStore() {
        return store;
    }

    public void setStore(int store) {
        this.store = store;
    }

    public Product() {

    }

    public Product(String id, String name, int price, int store) {
        this.id = id;
        this.name = name;
        this.price = price;
        this.store = store;
    }

    @Override
    public String toString() {
        return "product{" +
                "id='" + id + '\'' +
                ", name='" + name + '\'' +
                ", price=" + price +
                ", store=" + store +
                '}';
    }
}

ProductService.java

package com.ybchen.product_service.service;

import com.ybchen.product_service.domain.Product;

import java.util.List;

/**
 * @ClassName：ProductService
 * @Description：商品service
 * @Author：chenyb
 * @Date：2020/11/1 8:45 下午
 * @Versiion：1.0
 */
public interface ProductService {
    /**
     * 商品列表
     * @return
     */
    List<Product> listProduct();

    /**
     * 根据id查询商品
     * @param id
     * @return
     */
    Product findById(int id);
}

ProductServiceImpl.java

package com.ybchen.product_service.service.impl;

import com.ybchen.product_service.domain.Product;
import com.ybchen.product_service.service.ProductService;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;

import java.util.*;

/**
 * @ClassName：ProductServiceImpl
 * @Description：ProductService实现类
 * @Author：chenyb
 * @Date：2020/11/1 8:47 下午
 * @Versiion：1.0
 */
@Service
public class ProductServiceImpl implements ProductService {
    //初始化内存商品数据。模拟数据库中存储的商品
    private static final Map<Integer, Product> daoMap = new HashMap<>();

    @Value("${server.port}")
    private String port;
    static {
        for (int i = 0; i < 5; i++) {
            daoMap.put(i, new Product(i + "", "iphone_" + i, 1000 * i, 10));
        }
    }

    @Override
    public List<Product> listProduct() {
        Collection<Product> values = daoMap.values();
        return new ArrayList<>(values);
    }

    @Override
    public Product findById(int id) {
        Product product = daoMap.get(id);
        product.setName(product.getName()+"_"+port);
        return product;
    }
}

ProductServiceApplication.java

package com.ybchen.product_service;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class ProductServiceApplication {

    public static void main(String[] args) {
        SpringApplication.run(ProductServiceApplication.class, args);
    }

}

启动并查看监控台

　　启动2个服务，并查看监控台

搭建Eureka Client订单服务

创建项目

项目结构

pom.xml

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.18.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ybchen</groupId>
    <artifactId>order_service</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>order_service</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR6</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-ribbon</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>${spring-cloud.version}</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>

</project>

application.properties

# 服务端口号
server.port=8781
# 服务名称
spring.application.name=order-service
# 将服务注册到注册中心，eureka_service的地址
eureka.client.service-url.defaultZone:http://localhost:8761/eureka/

OrderServiceApplication.java

　　启动类添加Ribbon注解

    @Bean
    @LoadBalanced
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }

package com.ybchen.order_service;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;

@SpringBootApplication
public class OrderServiceApplication {
    /**
     * 负载均衡Ribbon
     * @return
     */
    @Bean
    @LoadBalanced
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }

    public static void main(String[] args) {
        SpringApplication.run(OrderServiceApplication.class, args);
    }

}

OrderController.java

package com.ybchen.order_service.controller;

import com.ybchen.order_service.service.ProductOrderService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("api/v1/order")
public class OrderController {
    @Autowired
    private ProductOrderService productOrderService;
    @RequestMapping("save")
    public Object save(@RequestParam("user_id")int userId,@RequestParam("product_id")int productId){
        return productOrderService.save(userId,productId);
    }
}

ProductOrder.java

package com.ybchen.order_service.domain;

import java.util.Date;

/**
 * 商品订单实体类
 */
public class ProductOrder {
    /**
     * 主键
     */
    private int id;
    /**
     * 商品名称
     */
    private String productName;
    /**
     * 订单流水号
     */
    private String tradeNo;
    /**
     * 价格，以分位单位
     */
    private int price;
    /**
     * 创建时间
     */
    private Date createTime;
    /**
     * 用户id
     */
    private String userId;
    /**
     * 用户名称
     */
    private String userName;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getProductName() {
        return productName;
    }

    public void setProductName(String productName) {
        this.productName = productName;
    }

    public String getTradeNo() {
        return tradeNo;
    }

    public void setTradeNo(String tradeNo) {
        this.tradeNo = tradeNo;
    }

    public int getPrice() {
        return price;
    }

    public void setPrice(int price) {
        this.price = price;
    }

    public Date getCreateTime() {
        return createTime;
    }

    public void setCreateTime(Date createTime) {
        this.createTime = createTime;
    }

    public String getUserId() {
        return userId;
    }

    public void setUserId(String userId) {
        this.userId = userId;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    @Override
    public String toString() {
        return "ProductOrder{" +
                "id=" + id +
                ", productName='" + productName + '\'' +
                ", tradeNo='" + tradeNo + '\'' +
                ", price=" + price +
                ", createTime=" + createTime +
                ", userId='" + userId + '\'' +
                ", userName='" + userName + '\'' +
                '}';
    }
}

ProductOrderService.java

package com.ybchen.order_service.service;

import com.ybchen.order_service.domain.ProductOrder;

public interface ProductOrderService {
    ProductOrder save(int userId, int productId);
}

ProductOrderServiceImpl.java

package com.ybchen.order_service.service.impl;

import com.ybchen.order_service.domain.ProductOrder;
import com.ybchen.order_service.service.ProductOrderService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;

/**
 * @ClassName：ProductOrderServiceImpl
 * @Description：产品订单实现类
 * @Author：chenyb
 * @Date：2020/11/2 11:34 下午
 * @Versiion：1.0
 */
@Service
public class ProductOrderServiceImpl implements ProductOrderService {
    @Autowired
    private RestTemplate restTemplate;
    /**
     * 下单接口
     * @param userId 用户id
     * @param productId 产品id
     * @return
     */
    @Override
    public ProductOrder save(int userId, int productId) {
        Object obj=productId;
        //get方式
        Object forObject = restTemplate.getForObject("http://product-service/api/v1/product/findById?id=" + productId, Object.class);
        //post方式
//        Map<String,String> map=new HashMap<>();
//        map.put("id","1");
//        String s = restTemplate.postForObject("http://product-service/api/v1/product/test", map, String.class);
//        System.out.println(s);
        System.out.println(forObject);
        //获取商品详情
        ProductOrder productOrder=new ProductOrder();
        productOrder.setTradeNo(UUID.randomUUID().toString());
        productOrder.setCreateTime(new Date());
        productOrder.setUserId(userId+"");
        return productOrder;
    }
}

测试负载均衡

feign实战

简介

　　改造订单服务，调用商品服务获取商品信息

官网例子

点我直达

改造订单服务

添加feign依赖

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.18.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ybchen</groupId>
    <artifactId>order_service</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>order_service</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR6</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!--openfeign依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</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>

</project>

启动类上添加注解

　　启动类上添加：@EnableFeignClients

添加一个接口

ProductClient.java

package com.ybchen.order_service.service;

import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

/**
 * 商品服务客户端
 */
// name=商品服务的服务名==========》spring.application.name=product-service
@FeignClient(name = "product-service")
@RequestMapping("/api/v1/product")
public interface ProductClient {

    @GetMapping("findById")
    String findById(@RequestParam("id") int id);
}

修改ProductOrderServiceImpl.java

原先

package com.ybchen.order_service.service.impl;

import com.ybchen.order_service.domain.ProductOrder;
import com.ybchen.order_service.service.ProductOrderService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;

/**
 * @ClassName：ProductOrderServiceImpl
 * @Description：产品订单实现类
 * @Author：chenyb
 * @Date：2020/11/2 11:34 下午
 * @Versiion：1.0
 */
@Service
public class ProductOrderServiceImpl implements ProductOrderService {
    @Autowired
    private RestTemplate restTemplate;
    /**
     * 下单接口
     * @param userId 用户id
     * @param productId 产品id
     * @return
     */
    @Override
    public ProductOrder save(int userId, int productId) {
        Object obj=productId;
        //get方式
        Object forObject = restTemplate.getForObject("http://product-service/api/v1/product/findById?id=" + productId, Object.class);
        //post方式
//        Map<String,String> map=new HashMap<>();
//        map.put("id","1");
//        String s = restTemplate.postForObject("http://product-service/api/v1/product/test", map, String.class);
//        System.out.println(s);
        System.out.println(forObject);
        //获取商品详情
        ProductOrder productOrder=new ProductOrder();
        productOrder.setTradeNo(UUID.randomUUID().toString());
        productOrder.setCreateTime(new Date());
        productOrder.setUserId(userId+"");
        return productOrder;
    }
}

修改为

package com.ybchen.order_service.service.impl;

import com.ybchen.order_service.domain.ProductOrder;
import com.ybchen.order_service.service.ProductClient;
import com.ybchen.order_service.service.ProductOrderService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.Date;
import java.util.UUID;

/**
 * @ClassName：ProductOrderServiceImpl
 * @Description：产品订单实现类
 * @Author：chenyb
 * @Date：2020/11/2 11:34 下午
 * @Versiion：1.0
 */
@Service
public class ProductOrderServiceImpl implements ProductOrderService {
    @Autowired
    private ProductClient productClient;

    /**
     * 下单接口
     *
     * @param userId    用户id
     * @param productId 产品id
     * @return
     */
    @Override
    public ProductOrder save(int userId, int productId) {
        //-----------调用商品服务开始------------
        String byId = productClient.findById(productId);
        System.out.println(byId);
        //-----------调用商品服务结束------------
        //获取商品详情
        ProductOrder productOrder = new ProductOrder();
        productOrder.setTradeNo(UUID.randomUUID().toString());
        productOrder.setCreateTime(new Date());
        productOrder.setUserId(userId + "");
        return productOrder;
    }
}

测试商品服务

补充(设置服务调用超时时间)

　　默认连接10秒，读取60秒，但是由于hystrix默认是1秒超时

官网案例，点我直达

application.properties

# 设置连接和读取超时时间
feign.client.config.default.connect-timeout=5000
feign.client.config.default.read-timeout=1100

服务降级熔断(Hystrix)

为什么要用？

　　在一个分布式系统里，一个服务依赖多个服务，可能存在某个服务调用失败，比如超时、异常等，如何能保证在一个依赖出问题的情况下，不会导致整体服务故障，可以通过Hystrix来解决。

官网例子

　　点我直达

修改订单服务

添加依赖

        <!--hystrix依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.18.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ybchen</groupId>
    <artifactId>order_service</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>order_service</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR6</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!--openfeign依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <!--hystrix依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</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>

</project>

启动类加注解

　　@EnableCircuitBreaker

修改控制层

　　添加注解，@HystrixCommand，并定义回调方法，返回值、入参必须一致！！！！

入参、返回值，不一致会报错

feign结合Hystrix

修改订单服务

开启hystrix

# 开启hystrix
feign.hystrix.enabled=true

ProductClient.java

package com.ybchen.order_service.service;

import com.ybchen.order_service.fallback.ProductClientFallBack;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.*;

/**
 * 商品服务客户端
 */
// name=商品服务的服务名==========》spring.application.name=product-service
@FeignClient(name = "product-service",fallback = ProductClientFallBack.class)
//@RequestMapping("/api/v1/product")
public interface ProductClient {

    @GetMapping("/api/v1/product/findById")
    String findById(@RequestParam("id") int id);
}

ProductClientFallBack.java

package com.ybchen.order_service.fallback;

import com.ybchen.order_service.service.ProductClient;
import org.springframework.stereotype.Component;

/**
 * 针对商品服务，做降级处理
 */
@Component
public class ProductClientFallBack implements ProductClient {
    @Override
    public String findById(int id) {
        System.out.println("商品服务被降级了~~~~~~~");
        return null;
    }
}

验证商品服务熔断

　　为什么对商品服务做了熔断，还返回这个结果呢，那是因为service实现类，内部发生了错误

熔断降级服务报警通知(重要)

　　下面写一些伪代码，比如：xxx微服务挂了，然后通过短信、邮件的方式，通知相应的开发人员，紧急处理事故等。

修改订单服务

修改hystrix超时时间

禁用超时时间(不推荐)

hystrix.command.default.execution.timeout.enabled=false

设置超时时间(推荐)

hystrix.command.default.execution.isolation.thread.timeoutInMilliseconds=4000

源码位置讲解

　　通过这种方法，还可以设置更多的hystrix默认值

断路器Dashboard监控仪表盘

修改订单服务

添加依赖

        <!--hystrix仪表盘-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.18.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ybchen</groupId>
    <artifactId>order_service</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>order_service</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR6</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!--openfeign依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <!--hystrix依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>
        <!--hystrix仪表盘-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</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>

</project>

pom.xml

启动类上加注解

　　添加：@EnableHystrixDashboard

修改配置文件

# 暴露全部的监控信息
management.endpoints.web.exposure.include=*

访问仪表盘

http://127.0.0.1:8781/hystrix

http://127.0.0.1:8781/actuator/hystrix.stream

　　仪表盘实际工作中用处不大(仁者见仁智者见智)，纯属学习用，具体参数，请自行百度，只要把微服务熔断/降级报警通知处理好，比啥都好

微服务网关Zuul

创建项目

项目结构

pom.xml

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.11.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ybchen</groupId>
    <artifactId>api-gateway</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>api-gateway</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Hoxton.SR8</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-zuul</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</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>

</project>

pom.xml

application.properties

server.port=8800
# 服务名称
spring.application.name=api-gateway
# 将服务注册到注册中心，eureka_service的地址
eureka.client.service-url.defaultZone:http://localhost:8761/eureka/

默认访问规则

　　http://gateway:port/service-id/**

　　比如，原先下单地址：127.0.0.1:8781/api/v1/order/save?user_id=1&product_id=1

　　现在下单地址：127.0.0.1:8800/order-service/api/v1/order/save?user_id=1&product_id=1

自定义路由规则

　　添加application.properties信息

# 自定义路由规则，语法：zuul.routes.服务名=自定义路由
zuul.routes.order-service=/apigate/**
# 不让默认的服务对外暴露接口，语法：zuul.ignored-patterns=服务名
zuul.ignored-patterns=/order-service/**
# 忽略所有服务
# zuul.ignored-patterns=*

处理http请求头为空的问题

　　默认zuul过滤3个值("Cookie", "Set-Cookie", "Authorization")，解决版本，设置为不过滤

源码解读

添加属性

# 处理http请求头为空的问题
zuul.sensitive-headers=

自定义Zuul过滤器之登录鉴权

改造api-gateway项目

新建LoginFilter类

　　新建该类，并继承ZuulFilter，重写里面的方法

package com.ybchen.apigateway.filter;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import java.io.PrintWriter;

import static org.springframework.cloud.netflix.zuul.filters.support.FilterConstants.PRE_TYPE;

/**
 * @ClassName：LoginFilter
 * @Description：登录过滤器
 * @Author：chenyb
 * @Date：2020/11/8 11:16 下午
 * @Versiion：1.0
 */
@Component //让Spring扫描到
public class LoginFilter extends ZuulFilter {
    /**
     * 过滤类型，有以下类型
     * 1、pre
     * 2、route
     * 3、post
     * 4、error
     *
     * @return
     */
    @Override
    public String filterType() {
        return PRE_TYPE;
    }

    /**
     * 过滤器顺序，越小越先执行
     *
     * @return
     */
    @Override
    public int filterOrder() {
        return 4;
    }

    /**
     * 过滤器是否生效
     *
     * @return
     */
    @Override
    public boolean shouldFilter() {
        //1、获取上下文
        RequestContext currentContext = RequestContext.getCurrentContext();
        //2、获取HttpServletRequest
        HttpServletRequest request = currentContext.getRequest();
        //3、拿到请求路径，判断是否进行拦截
        //System.out.println(request.getRequestURL()); //http://127.0.0.1:8800/apigate/order/api/v1/order/save
        //System.out.println(request.getRequestURI()); ///apigate/order/api/v1/order/save
        String url = request.getRequestURI();
        System.out.println("请求路径url=========>" + url);
        if ((url == null ? "" : url.toLowerCase()).startsWith("/apigate/order")) {
            return true;
        }
        return false;
    }

    /**
     * 过滤器逻辑，业务逻辑
     *
     * @return
     * @throws ZuulException
     */
    @Override
    public Object run() throws ZuulException {
        System.out.println("请求被拦截啦==============");
        //JWT方式
        //1、获取上下文
        RequestContext currentContext = RequestContext.getCurrentContext();
        //2、获取HttpServletRequest
        HttpServletRequest request = currentContext.getRequest();
        //3、拿到token
        String token = request.getHeader("token"); //请求头拿token
        if (token == null || "".equals(token)) {
            token = request.getParameter("token"); //get方式拿token
        }
        //登录校验逻辑，这里推荐JWT方式，做登录鉴权
        if (token == null || "".equals(token)) {
            //4、不让继续往下走
            currentContext.setSendZuulResponse(false);
            //5、设置状态码，401，Unauthorized
            currentContext.setResponseStatusCode(HttpStatus.UNAUTHORIZED.value());
            sendJsonMessage(currentContext.getResponse(),"用户未登录");
        }
        return null;
    }
    /**
     * 响应json数据给前端
     *
     * @param response
     * @param obj
     */
    private void sendJsonMessage(HttpServletResponse response, Object obj) {
        try {
            ObjectMapper objectMapper = new ObjectMapper();
            response.setContentType("application/json;charset=utf-8");
            PrintWriter writer = response.getWriter();
            writer.print(objectMapper.writeValueAsString(obj));
            writer.close();
            writer.flush();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

用户登录鉴权测试

补充

　　登录鉴权，推荐使用JWT方式，下面我提供我之前的一个项目，JWT的工具类，和拦截器的部分关键代码

        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt</artifactId>
            <version>0.7.0</version>
        </dependency>

pom.xml依赖

package net.ybclass.online_ybclass.utils;

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import net.ybclass.online_ybclass.model.entity.User;

import java.util.Date;

/**
 * JWT工具类
 * 注意点：
 * 1、生成的token，是可以通过base64进行解密出铭文信息
 * 2、base64进行解密出明文信息，修改再进行编码，则会解密失败
 * 3、无法作废已颁布的token，除非改密钥
 */
public class JWTUtils {
    /**
     * 过期时间，一周
     */
    static final long EXPIRE = 60000 * 60 * 24 * 7;
    /**
     * 加密密钥
     */
    private static final String SECRET = "ybclass.net168";
    /**
     * 令牌前缀
     */
    private static final String TOKEN_PREFIX = "ybclass";
    /**
     * 主题
     */
    private static final String SUBJECT = "ybclass";

    /**
     * 根据用户信息，生成令牌
     *
     * @param user
     * @return
     */
    public static String geneJsonWebToken(User user) {
        String token = Jwts.builder().setSubject(SUBJECT)
                .claim("head_img", user.getHeadImg())
                .claim("id", user.getId())
                .claim("name", user.getName())
                .setIssuedAt(new Date()) //令牌颁布时间
                .setExpiration(new Date(System.currentTimeMillis() + EXPIRE)) //过期时间
                .signWith(SignatureAlgorithm.HS256, SECRET) //加密方式
                .compact();
        token = TOKEN_PREFIX + token;
        return token;
    }

    /**
     * 校验token方法
     *
     * @param token
     * @return
     */
    public static Claims checkJWT(String token) {
        try {
            final Claims claims = Jwts.parser()
                    .setSigningKey(SECRET)
                    .parseClaimsJws(token.replace(TOKEN_PREFIX, ""))
                    .getBody();
            return claims;
        } catch (Exception e) {
            return null;
        }
    }
}

JWTUtils.java

try {
            String accesToken = request.getHeader("token");
            if (accesToken == null) {
                accesToken = request.getParameter("token");
            }
            if (StringUtils.isNoneBlank(accesToken)) {
                Claims claims = JWTUtils.checkJWT(accesToken);
                if (claims == null) {
                    sendJsonMessage(response, JsonData.buildError("登陆过期，请重新登陆"));
                    //告诉登陆过期，重新登陆
                    return false;
                }
                Integer id = (Integer) claims.get("id");
                String name = (String) claims.get("name");
                request.setAttribute("user_id", id);
                request.setAttribute("name", name);
                return true;
            }
        } catch (Exception e) {
        }
        //登陆失败
        sendJsonMessage(response, JsonData.buildError("登陆过期，请重新登陆"));
        return false;

=================
        User user = userMapper.findByPhoneAndPwd(phone, CommonUtils.MD5(pwd));
        return user == null ? null : JWTUtils.geneJsonWebToken(user);

拦截器部分代码

网关Zuul接口限流

　　采用谷歌guava框架，网关限流

改造api-gateway项目

创建OrderRatelimiterFilter

　　然后继承ZuulFilter，并使用springcloud继承的guava技术，只针对订单接口限流！！！

package com.ybchen.apigateway.filter;

import com.google.common.util.concurrent.RateLimiter;
import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.springframework.http.HttpStatus;

import javax.servlet.http.HttpServletRequest;

import static org.springframework.cloud.netflix.zuul.filters.support.FilterConstants.PRE_TYPE;

/**
 * @ClassName：OrderRateLimiterFilter
 * @Description：订单接口限流
 * @Author：chenyb
 * @Date：2020/11/9 11:32 下午
 * @Versiion：1.0
 */
public class OrderRateLimiterFilter extends ZuulFilter {
    //限流令牌，每秒创建多少令牌，注意：springcloud 默认集成guava
    private static final RateLimiter RATE_LIMITER = RateLimiter.create(1000);

    @Override
    public String filterType() {
        return PRE_TYPE;
    }

    @Override
    public int filterOrder() {
        return -4;
    }

    @Override
    public boolean shouldFilter() {
        //1、获取上下文
        RequestContext currentContext = RequestContext.getCurrentContext();
        //2、获取HttpServletRequest
        HttpServletRequest request = currentContext.getRequest();
        String url = request.getRequestURI();
        System.out.println("限流请求路径url=========>" + url);
        //只对订单接口限流
        if ((url == null ? "" : url.toLowerCase()).startsWith("/apigate/order")) {
            return true;
        }
        return false;
    }

    @Override
    public Object run() throws ZuulException {
        RequestContext currentContext = RequestContext.getCurrentContext();
        HttpServletRequest request = currentContext.getRequest();
        if (!RATE_LIMITER.tryAcquire()) {
            currentContext.setSendZuulResponse(false);
            currentContext.setResponseStatusCode(HttpStatus.TOO_MANY_REQUESTS.value());
        }
        return null;
    }
}

Zuul集群

　　技术栈：nginx+lvs+keepalive

案例源码下载

链接: https://pan.baidu.com/s/1bNIh-8nSCMcU7FjVVzlBnA  密码: 4wf9