网关简绍
就是网络的关口，负责请求的路由、转发、身份校验。
引入网关依赖
1
2
3
4
5
6
7
8
9
10
11
12
13
14
| <dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>
<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-loadbalancer</artifactId>
</dependency>
</dependencies>
|
配置路由规则
id： 路由唯一标示
uri: 路由目标地址
predicates: 路由断言，判断请求是否符合当前路由
filters: 路由过滤器，对请求或响应做特殊处理
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
| spring:
application:
name: hm-gateway
cloud:
nacos:
server-addr: 127.0.0.1:8848
gateway:
routes:
- id: item-service
uri: lb://item-service
predicates:
- Path=/items/**,/search/**
- id: user-service
uri: lb://user-service
predicates:
- Path=/users/**,/addresses/**
|
更多规则的路由断言
路由过滤器
使用 路由过滤器, 配置 AddRequestHeader 添加请求头
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
| server:
port: 8080
spring:
application:
name: hm-gateway
cloud:
nacos:
server-addr: 127.0.0.1:8848
gateway:
routes:
- id: item-service
uri: lb://item-service
predicates:
- Path=/items/**,/search/**
filters:
- AddRequestHeader=truth, anyone long-press like button will be rich
- id: user-service
uri: lb://user-service
predicates:
- Path=/users/**,/addresses/**
|
使用 @RequestHeader(value = “truth”, required = false)String truth 获取
1
2
3
| public void test(@RequestHeader(value = "truth", required = false)String truth) {
System.out.println("truth" + truth);
}
|
可以配置全局 默认过滤器, 使用 default-filters 与 routes 同级
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
| server:
port: 8080
spring:
application:
name: hm-gateway
cloud:
nacos:
server-addr: 127.0.0.1:8848
gateway:
routes:
- id: item-service
uri: lb://item-service
predicates:
- Path=/items/**,/search/**
- id: user-service
uri: lb://user-service
predicates:
- Path=/users/**,/addresses/**
default-filters:
- AddRequestHeader=truth, anyone long-press like button will be rich
|
自定义过滤器
- GatewayFilter：路由过滤器，作用于任意指定的路由；默认不生效，要配置到路由后生效。
- GlobalFilter：全局过滤器，作用范围是所有路由；声明后自动生效。
过滤器处理流程
两种过滤器的过滤方法签名完全一致：
- ServerWebExchange 请求上下文， 包含整个过滤器链中共享数据
- GatewayFilterChain 过滤器链。当前过滤器执行完后，要调用过滤器链中的下一个过滤器
1
| Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain);
|
GlobalFilter过滤器
定义ordered 用来定义启动顺序
全局执行过滤器
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
| @Component
public class MyGlobalFilter implements GlobalFilter, Ordered {
@Override
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
ServerHttpRequest request = exchange.getRequest();
System.out.println("GlobalFilter pre阶段 执行了。");
return chain.filter(exchange);
}
@Override
public int getOrder() {
return 0;
}
}
|
GatewayFilter过滤器
自定义过滤器， 需要在配置文件中主动配置才能去调用
1
2
3
4
5
6
7
8
9
10
11
12
13
14
| @Component
public class PrintAnyGatewayFilterFactory extends AbstractGatewayFilterFactory {
@Override
public GatewayFilter apply(Object config) {
// 使用内部装饰类，定义启动顺序
return new OrderedGatewayFilter(new GatewayFilter() {
@Override
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
System.out.println("PrintAnyGateway 执行了");
return chain.filter(exchange);
}
}, 1);
}
}
|
具体配置文件
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
| server:
port: 8080
spring:
application:
name: hm-gateway
cloud:
nacos:
server-addr: 127.0.0.1:8848
gateway:
routes:
- id: item-service
uri: lb://item-service
predicates:
- Path=/items/**,/search/**
- id: user-service
uri: lb://user-service
predicates:
- Path=/users/**,/addresses/**
default-filters:
- AddRequestHeader=truth, anyone long-press like button will be rich
- PrintAny
|
定义过滤器读取参数信息
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
| server:
port: 8080
spring:
application:
name: hm-gateway
cloud:
nacos:
server-addr: 127.0.0.1:8848
gateway:
routes:
- id: item-service
uri: lb://item-service
predicates:
- Path=/items/**,/search/**
- id: user-service
uri: lb://user-service
predicates:
- Path=/users/**,/addresses/**
default-filters:
- AddRequestHeader=truth, anyone long-press like button will be rich
- PrintAny=1,2,3
|
从过滤器取 1，2，3, 配置全局 PrintAnyGatewayFilterFactory 将 Config 委托给父类， 使用 shortcutFieldOrder 按顺序取读取信息
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
| @Component
public class PrintAnyGatewayFilterFactory extends AbstractGatewayFilterFactory<PrintAnyGatewayFilterFactory.Config> {
@Override
public GatewayFilter apply(Config config) {
return new OrderedGatewayFilter(new GatewayFilter() {
@Override
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
String a = config.getA();
String b = config.getB();
String c = config.getC();
System.out.println(a + b + c);
System.out.println("PrintAnyGateway 执行了");
return chain.filter(exchange);
}
}, 1);
}
@Data
public static class Config{
private String a;
private String b;
private String c;
}
public PrintAnyGatewayFilterFactory(){
super(Config.class);
}
@Override
public List<String> shortcutFieldOrder() {
return List.of("a", "b", "c");
}
}
|
