Docker

# 1.为什么需要网关


![image.png](/static/img/468eda077abcf30ae8735a661f62d2e4.image.webp)
# 2.操作
## （1）创建项目引入依赖服务发现和gateway网关依赖


![image.png](/static/img/cdb250b04a724143b93c399eccf551aa.image.webp)
```pom
    <dependencies>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
        </dependency>
    </dependencies>
```
## (2)实现请求路由功能

![image.png](/static/img/b3d370fad4372e7db7564266f75ee1ab.image.webp)

```config
spring:
  application:
    name: gateway
  cloud:
    nacos:
      server-addr: localhost:80
    gateway:
      routes:
        - id: user-service
          uri: lb://userservice # 路由的目标地址
          predicates:
            - Path=/user/** # 判断路径是否是user开头
        - id: order-service
          uri: lb://orderservice
          predicates:
            - Path=/order/**
server:
  port: 10010
```
## (3)总结

![image.png](/static/img/092984b9635df7b42947f1b9a0317748.image.webp)
## （4）路由断言工厂

![image.png](/static/img/dd4033b163041b4cc82c76549ae0b5ab.image.webp)
## （5）过滤器工厂

![image.png](/static/img/a0a2201ea4ca8e3a8f57589b2fd42825.image.webp)
代码示例

```config
    gateway:
      routes:
        - id: user-service
          uri: lb://userservice # 路由的目标地址
          predicates:
            - Path=/user/** # 判断路径是否是user开头
        - id: order-service
          uri: lb://orderservice
          predicates:
            - Path=/order/**
          filters:
            - AddRequestHeader=Truth,Hello world # 添加的过滤器
```
向所有微服务添加过滤器
**默认过滤器**
![image.png](/static/img/ebcac6233ff72d094445a87df0f0e803.image.webp)
**全局过滤器**
编写代码自定义过滤逻辑
实现golabalFilter接口
![image.png](/static/img/71dcf5725e3c2359d6830db05773b13c.image.webp)
**案例：**

![image.png](/static/img/37a775fd9f108467e2badd3ab3339724.image.webp)

```java
package cn.itcast.gateway;

import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.annotation.Order;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.stereotype.Component;
import org.springframework.util.MultiValueMap;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;



@Order(-1) // 定义过滤器的顺序 默认最低 数字越小最先执行
@Component
public class AuthorizeFilter implements GlobalFilter {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

//        1.获取请求参数
        ServerHttpRequest request =exchange.getRequest();
        MultiValueMap<String,String> params= request.getQueryParams();
//        2获取参数中的authorization
        String auth = params.getFirst("authorization");
        if ("admin".equals(auth)){
            return chain.filter(exchange); // 放行
        }
        // 否 拦截

        // 设置状态码
        exchange.getResponse().setStatusCode(HttpStatus.UNAUTHORIZED);
        // 拦截请求
        return exchange.getResponse().setComplete();
        //
    }
}

```
**过滤器执行顺序**
1.当前路由过滤器
2.DefaultFilter
3.GlobalFilter
![image.png](/static/img/ebd52358f434cca28a1c79e48bc902e9.image.webp)
![image.png](/static/img/a818ed1a3cfe45b36dec21858889bdd5.image.webp)
![image.png](/static/img/353c55977b8734c89602637806be49c5.image.webp)
## （6）跨域问题

![image.png](/static/img/07020596503477f58e5f6bfb1c378411.image.webp)

统一网关Gateway

# 1.Feign介绍




![image.png](/static/img/6ce56e37e890a10f6d89a6c509ad4cc7.image.webp)
# 2.定义和使用客户端
   ## (1)引入依赖
   
![image.png](/static/img/401192c64c830db97e495dce267f3287.image.webp)

```config

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
```
   ## (2)在order-service的启动类中加注释开启Fegin的功能
   
![image.png](/static/img/b9d4e7609cf614ea34849eeeb1f72892.image.webp)
   ## (3)编写Feign客户端
   
![image.png](/static/img/91fcbe5e62a20c13603cc5a69a980cbb.image.webp)

![image.png](/static/img/a84e48bdc4b91bf4e32b0fb8e565abb4.image.webp)

```java
package cn.itcast.order.clients;


import org.springframework.cloud.openfeign.FeignClient;

@FeignClient("userservice")
public interface UserClient {
}
```
## (4)调用举例

```java
@Service
public class OrderService {

    @Autowired
    private OrderMapper orderMapper;
    @Autowired
    private UserClient userClient;

    public Order queryOrderById(Long orderId) {
        // 1.查询订单·
        Order order = orderMapper.findById(orderId);
        
        User user = userClient.getUserById(order.getUserId());
        
        order.setUser(user);
        // 4.返回
        return order;
    }
}
```
# 3.配置feign
法一
![image.png](/static/img/030f9d4c9e50819516f8e857674b757b.image.webp)
法二
![image.png](/static/img/444b464a7cdfa0fea434bfd5c59eade1.image.webp)
# 4.feign性能优化
默认使用URLconnection
使用连接池代替URLconnection
![image.png](/static/img/74b12e1c38ed52ef1dc301d808f4ef37.image.webp)
连接池配置
![image.png](/static/img/95b8089089660df394b7c46cbcd175e2.image.webp)

```pom

        <dependency>
            <groupId>io.github.openfeign</groupId>
            <artifactId>feign-httpclient</artifactId>
        </dependency>
```

```config
feign:
  client:
    config:
      default:
        loggerLevel: FULL
  httpclient:
    enabled: true # 开启feign对httpclient的支持
    max-connections: 200 # 最大连接数
    max-connections-per-route: 50 # 每个路径的最大连接数
```
总结

![image.png](/static/img/f3605acba9227a3cb5aea5e1aca2edb6.image.webp)
# 5.feign的最佳实现

![image.png](/static/img/c107bb7e8e57c76310c9087330792d67.image.webp)
抽取具体实现
## （1）创建module

![image.png](/static/img/c51456bc900bc69c1bba3ac192fa49aa.image.webp)
## （2）将pojo和cliens的代码移动到feign-api中

![image.png](/static/img/41093267c68ad955916ec466070a0b0d.image.webp)
![image.png](/static/img/52f6b835c75a3822373600117d5886b9.image.webp)

Feign

# Nacos相关设置
## 1.权限配置


![image.png](/static/img/da99d2b0def0b3cb87fd5f5182a00dc9.image.webp)
在nacos中修改服务器权重如果为0则不访问
## 2.环境隔离

![image.png](/static/img/33600d8464bb99402c8118ee3134190e.image.webp)
![image.png](/static/img/9108aff8b549a3aca93573b26b1a3029.image.webp)
![image.png](/static/img/e5bc6c9faee42dbe8b1eef1b4e3e52d2.image.webp)
每一个namespace都有一个唯一id  
![image.png](/static/img/871a332ef755e496833b80e9d429f14d.image.webp)
不同namespace无法访问
## 3.nacos配置管理
### (1)统一配置管理
实现配置更改热更新
![image.png](/static/img/be686c67806135231a77ad6cdda367ca.image.webp)
![image.png](/static/img/a75c3967bfdfd2778f8df9ab2c601497.image.webp)
![image.png](/static/img/c1b38a06eed0c4259c070d1ad8643aa1.image.webp)
引入依赖
![image.png](/static/img/935a59db453ce409eb73626c372d6692.image.webp)

```config

        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
        </dependency>
```
编写引导文件
![image.png](/static/img/acee28a0dbac57a1f46f7dd0ed700a81.image.webp)
### (2)配置热更新
![image.png](/static/img/c531647828c091f73a23f2dfeaeb060d.image.webp)
![image.png](/static/img/dfe8aa2994aa07e813d51a210e1b6d7d.image.webp)

Nacos相关设置

## 1.认识Nacos



![image.png](/static/img/56a5b62ba901b5d3a48ac5d14a3fc3b8.image.webp)
## 2.安装Nacos
### (1)访问github官网下载Nacos安装包

![image.png](/static/img/801dfe9e64ce81e1a49df9068c13929e.image.webp)
### (2)解压安装包到全英文的目录下

![image.png](/static/img/e790784019453e0c25c5eb37e135435e.image.webp)
<br>
nacos默认的配置文件在conf下的application.properties默认端口是8848
### (3)启动Nacos
进入bin目录显示4个文件

![image.png](/static/img/fb8dac00019a961615fb056666b150e1.image.webp)
### (4)代码中导入nacos依赖

```config

            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>2.2.5.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
```
### (5)代码中导入nacos客户端依赖

```config
<dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
 </dependency>
```
### (6)客户端添加yml配置文件

```config
spring:
#    nacos 配置
  cloud:
    nacos:
      server-addr: localhost:80
```
### (7)nacos集群划分
添加yml文件

```config
#    nacos 配置
  cloud:
    nacos:
      server-addr: localhost:80
      discovery:
        cluster-name: HZ
```
集群效果
![image.png](/static/img/774974f00b032105f423eba363d9f934.image.webp)
### (8)实现优先访问本地集群
修改yml中的规则

```config
userservice:
  ribbon:
    NFLoadBalancerRuleClassName: com.alibaba.cloud.nacos.ribbon.NacosRule
```