springcloud gateway如何实现路由和负载均衡

简介：

gateway主要是做路由 负载，过滤 主要是替代zuul 1.x 性能比zuul好 zuul是基于

Servlet ，gateway是基于spring-webflux 用的netty+reactor

yml文件

实现路由 负载 的配置 亲自测试

1. spring:
2. application:
3. name: xgyx_gateway
4. cloud:
5. discovery:
6. locator:
7. enabled: true
8. gateway:
9. routes:
10. - id: a #随便定义不重复就好
11. uri: lb://xgyx-welfareservice-x #服务名称
12. predicates:
13. - Path=/m/** #前端访问需加入例如 http:ip:port/m
14. filters:
15. - StripPrefix=1 #访问后端服务过滤掉m 必填否则找不到后端服务也可以在服务加上统一路径
16. - name: Hystrix #熔断
17. args:
18. name: default
19. fallbackUri: forward:/defaultfallback #熔断后访问路径
20. - id: b
21. uri: lb://xgyx-welfareservice
22. predicates:
23. - Path=/welfare/**
24. filters:
25. - StripPrefix=1
26. - name: Hystrix
27. args:
28. name: default
29. fallbackUri: forward:/fallback
30. #熔断时间
31. hystrix:
32. command:
33. default:
34. execution:
35. isolation:
36. strategy: SEMAPHORE
37. thread:
38. timeoutInMilliseconds: 300000 #熔断时间

上面是用了两天时间根据官网上的demo和说明自己测的可以使用 上面 stripPrefix 用的是 PrefixPath 过滤器 其他过滤器使用可以看官网

springcloud gateway 自定义负载均衡

相关类及接口

LoadbalancerClientFilter：使用ribbon负载均衡，默认使用该类（已不推荐使用）

1. /** @deprecated */
2. @Deprecated
3. public class LoadBalancerClientFilter implements GlobalFilter, Ordered {
4. public static final int LOAD_BALANCER_CLIENT_FILTER_ORDER = 10100;
5. private static final Log log = LogFactory.getLog(LoadBalancerClientFilter.class);
6. protected final LoadBalancerClient loadBalancer;
7. private LoadBalancerProperties properties;
8.  
9. public LoadBalancerClientFilter(LoadBalancerClient loadBalancer, LoadBalancerProperties properties) {
10. this.loadBalancer = loadBalancer;
11. this.properties = properties;
12. }
13.  
14. public int getOrder() {
15. return 10100;
16. }
17.  
18. public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
19. URI url = (URI)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR);
20. String schemePrefix = (String)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_SCHEME_PREFIX_ATTR);
21. if (url != null && ("lb".equals(url.getScheme()) || "lb".equals(schemePrefix))) {
22. ServerWebExchangeUtils.addOriginalRequestUrl(exchange, url);
23. if (log.isTraceEnabled()) {
24. log.trace("LoadBalancerClientFilter url before: " + url);
25. }
26.  
27. ServiceInstance instance = this.choose(exchange);
28. if (instance == null) {
29. throw NotFoundException.create(this.properties.isUse404(), "Unable to find instance for " + url.getHost());
30. } else {
31. URI uri = exchange.getRequest().getURI();
32. String overrideScheme = instance.isSecure() ? "https" : "http";
33. if (schemePrefix != null) {
34. overrideScheme = url.getScheme();
35. }
36.  
37. URI requestUrl = this.loadBalancer.reconstructURI(new DelegatingServiceInstance(instance, overrideScheme), uri);
38. if (log.isTraceEnabled()) {
39. log.trace("LoadBalancerClientFilter url chosen: " + requestUrl);
40. }
41.  
42. exchange.getAttributes().put(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR, requestUrl);
43. return chain.filter(exchange);
44. }
45. } else {
46. return chain.filter(exchange);
47. }
48. }
49.  
50. protected ServiceInstance choose(ServerWebExchange exchange) {
51. return this.loadBalancer.choose(((URI)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR)).getHost());
52. }
53. }

说明：默认使用该类，可通过下述方法使用ReactiveLoadbalancerClientFilter

​"You already have RibbonLoadBalancerClient on your classpath. It will be used by default.
As Spring Cloud Ribbon is in maintenance mode. We recommend switching to " + BlockingLoadBalancerClient.class.getSimpleName() + " instead.
In order to use it, set the value of `spring.cloud.loadbalancer.ribbon.enabled` to `false`
or remove spring-cloud-starter-netflix-ribbon from your project."

ReactiveLoadBalancerClientFilter：负载均衡拦截器

1. public class ReactiveLoadBalancerClientFilter implements GlobalFilter, Ordered {
2. private static final Log log = LogFactory.getLog(ReactiveLoadBalancerClientFilter.class);
3. private static final int LOAD_BALANCER_CLIENT_FILTER_ORDER = 10150;
4. private final LoadBalancerClientFactory clientFactory;
5. private LoadBalancerProperties properties;
6. public ReactiveLoadBalancerClientFilter(LoadBalancerClientFactory clientFactory, LoadBalancerProperties properties) {
7. this.clientFactory = clientFactory;
8. this.properties = properties;
9. }
10.  
11. public int getOrder() {
12. return 10150;
13. }
14.  
15. public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
16. URI url = (URI)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR);
17. String schemePrefix = (String)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_SCHEME_PREFIX_ATTR);
18. if (url != null && ("lb".equals(url.getScheme()) || "lb".equals(schemePrefix))) {
19. //url不为null且协议为lb，或者url以lb开头
20.  
21. ServerWebExchangeUtils.addOriginalRequestUrl(exchange, url);
22. if (log.isTraceEnabled()) {
23. log.trace(ReactiveLoadBalancerClientFilter.class.getSimpleName() + " url before: " + url);
24. }
25.  
26. return this.choose(exchange).doOnNext((response) -> {
27. //获取ServiceInstance实例，进行一些处理
28.  
29. if (!response.hasServer()) {
30. //如果没有serviceInstance，直接抛出异常
31.  
32. throw NotFoundException.create(this.properties.isUse404(), "Unable to find instance for " + url.getHost());
33. } else { //如果有serviceInstance，进行相关处理
34. URI uri = exchange.getRequest().getURI();
35. String overrideScheme = null;
36. if (schemePrefix != null) {
37. overrideScheme = url.getScheme();
38. }
39.  
40. DelegatingServiceInstance serviceInstance = new DelegatingServiceInstance((ServiceInstance)response.getServer(), overrideScheme);
41. URI requestUrl = LoadBalancerUriTools.reconstructURI(serviceInstance, uri);
42. if (log.isTraceEnabled()) {
43. log.trace("LoadBalancerClientFilter url chosen: " + requestUrl);
44. }
45.  
46. exchange.getAttributes().put(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR, requestUrl);
47. }
48. }).then(chain.filter(exchange));
49. } else {
50. return chain.filter(exchange); //如果获取不到serviceInstance，直接进行后续过滤
51. }
52. }
53.  
54. private Mono<Response<ServiceInstance>> choose(ServerWebExchange exchange) {
55. URI uri = (URI)exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR);
56. ReactorLoadBalancer<ServiceInstance> loadBalancer = (ReactorLoadBalancer)this.clientFactory.getInstance(uri.getHost(), ReactorLoadBalancer.class, new Class[]{ServiceInstance.class});
57. if (loadBalancer == null) {
58. throw new NotFoundException("No loadbalancer available for " + uri.getHost());
59. } else {
60. return loadBalancer.choose(this.createRequest());
61. }
62. }//选择服务实例
63.  
64. private Request createRequest() {
65. return ReactiveLoadBalancer.REQUEST;
66. }
67. }

ReactorLoadBalancer：负载均衡接口

1. public interface ReactorLoadBalancer<T> extends ReactiveLoadBalancer<T> {
2. Mono<Response<T>> choose(Request request);
3. default Mono<Response<T>> choose() {
4. return this.choose(REQUEST);
5. }
6. }
7. ***********************
8. public interface ReactorServiceInstanceLoadBalancer extends ReactorLoadBalancer<ServiceInstance> {
9. }

RoundRobinLoadbalancer：负载均衡使用轮询

1. public class RoundRobinLoadBalancer implements ReactorServiceInstanceLoadBalancer {
2. private static final Log log = LogFactory.getLog(RoundRobinLoadBalancer.class);
3. private final AtomicInteger position;
4. private ObjectProvider<ServiceInstanceListSupplier> serviceInstanceListSupplierProvider;
5. private final String serviceId;
6.  
7. ************
8. 构造方法
9.  
10. public RoundRobinLoadBalancer(ObjectProvider<ServiceInstanceListSupplier> serviceInstanceListSupplierProvider, String serviceId) {
11. public RoundRobinLoadBalancer(ObjectProvider<ServiceInstanceListSupplier> serviceInstanceListSupplierProvider, String serviceId, int seedPosition) {
12.  
13. ************
14. 普通方法
15.  
16. public Mono<Response<ServiceInstance>> choose(Request request) {
17. if (this.serviceInstanceListSupplierProvider != null) {
18. ServiceInstanceListSupplier supplier = (ServiceInstanceListSupplier)this.serviceInstanceListSupplierProvider.getIfAvailable(NoopServiceInstanceListSupplier::new);
19. return ((Flux)supplier.get()).next().map(this::getInstanceResponse);
20. } else {
21. ServiceInstanceSupplier supplier = (ServiceInstanceSupplier)this.serviceInstanceSupplier.getIfAvailable(NoopServiceInstanceSupplier::new);
22. return ((Flux)supplier.get()).collectList().map(this::getInstanceResponse);
23. }
24. }
25.  
26. private Response<ServiceInstance> getInstanceResponse(List<ServiceInstance> instances) {
27. if (instances.isEmpty()) {
28. log.warn("No servers available for service: " + this.serviceId);
29. return new EmptyResponse();
30. } else {
31. int pos = Math.abs(this.position.incrementAndGet());
32. ServiceInstance instance = (ServiceInstance)instances.get(pos % instances.size());
33. return new DefaultResponse(instance);
34. }
35. }//使用轮询获取实例
36. }

示例：

参数id为偶数时，输出hello new version

网关

配置文件

1. spring:
2. application:
3. name: hello-gateway
4. cloud:
5. consul:
6. host: 172.18.0.20
7. port: 8500
8. loadbalancer:
9. ribbon:
10. enabled: false
11. gateway:
12. routes:
13. - id: myRoute
14. uri: lb://hello-service
15. predicates:
16. - Path=/hello

自定义过滤器

1. @Component
2. public class CustomLoadBalancerClientFilter implements GlobalFilter, Ordered {
3. private static final Log log = LogFactory.getLog(org.springframework.cloud.gateway.filter.ReactiveLoadBalancerClientFilter.class);
4.  
5. @Resource
6. private final LoadBalancerClientFactory clientFactory;
7.  
8. @Resource
9. private LoadBalancerProperties properties;
10.  
11. public CustomLoadBalancerClientFilter(LoadBalancerClientFactory clientFactory, LoadBalancerProperties properties) {
12. this.clientFactory = clientFactory;
13. this.properties = properties;
14. }
15.  
16. public int getOrder() {
17. return 10149;
18. }
19.  
20. public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
21. URI url = exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR);
22. String schemePrefix = exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_SCHEME_PREFIX_ATTR);
23. if (url != null && ("lb".equals(url.getScheme()) || "lb".equals(schemePrefix))) {
24. ServerWebExchangeUtils.addOriginalRequestUrl(exchange, url);
25. if (log.isTraceEnabled()) {
26. log.trace(ReactiveLoadBalancerClientFilter.class.getSimpleName() + " url before: " + url);
27. }
28.  
29. return this.choose(exchange).doOnNext((response) -> {
30. if (!response.hasServer()) {
31. throw NotFoundException.create(this.properties.isUse404(), "Unable to find instance for " + url.getHost());
32. } else {
33. URI uri = exchange.getRequest().getURI();
34. String overrideScheme = null;
35. if (schemePrefix != null) {
36. overrideScheme = url.getScheme();
37. }
38.  
39. int id=Integer.parseInt(Objects.requireNonNull(exchange.getRequest().getQueryParams().getFirst("id")));
40. if (id%2==0){
41. while (!"new".equals(response.getServer().getMetadata().get("version"))){
42. try {
43. response=this.choose(exchange).toFuture().get();
44. }catch (Exception e){
45. System.out.println(e.getMessage());
46. }
47. }
48. }
49.  
50. DelegatingServiceInstance serviceInstance = new DelegatingServiceInstance(response.getServer(), overrideScheme);
51.  
52. System.out.println(exchange.getRequest().getQueryParams().getFirst("id")+"对应server的version为："+serviceInstance.getMetadata().get("version"));
53. URI requestUrl = LoadBalancerUriTools.reconstructURI(serviceInstance, uri);
54. if (log.isTraceEnabled()) {
55. log.trace("LoadBalancerClientFilter url chosen: " + requestUrl);
56. }
57.  
58. exchange.getAttributes().put(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR, requestUrl);
59. }
60. }).then(chain.filter(exchange));
61. } else {
62. return chain.filter(exchange);
63. }
64. }
65.  
66. private Mono<Response<ServiceInstance>> choose(ServerWebExchange exchange) {
67. URI uri = exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR);
68. assert uri != null;
69. ReactorLoadBalancer<ServiceInstance> loadBalancer = this.clientFactory.getInstance(uri.getHost(), ReactorLoadBalancer.class, new Class[]{ServiceInstance.class});
70. if (loadBalancer == null) {
71. throw new NotFoundException("No loadbalancer available for " + uri.getHost());
72. } else {
73. return loadBalancer.choose(this.createRequest());
74. }
75. }
76.  
77. private Request createRequest() {
78. return ReactiveLoadBalancer.REQUEST;
79. }
80. }

同名应用hello-service1

配置文件

1. spring:
2. application:
3. name: hello-service
4. cloud:
5. consul:
6. host: 172.18.0.20
7. port: 8500
8. discovery:
9. instance-id: ${spring.application.name}-${random.int}
10. tags: version=old

controller 层

1. @RestController
2. public class HelloController {
3. @RequestMapping("/hello")
4. public String hello(){
5. return "hello old version";
6. }
7. }

同名应用hello-service2

配置文件

1. spring:
2. application:
3. name: hello-service
4. cloud:
5. consul:
6. host: 172.18.0.20
7. port: 8500
8. discovery:
9. instance-id: ${spring.application.name}-${random.int}
10. tags: version=new

controller 层

1. @RestController
2. public class HelloController {
3. @RequestMapping("/hello")
4. public String hello(){
5. return "hello new version";
6. }
7. }

测试输出

consul注册的应用

参数测试

当id为偶数时，输出为hello new version

以上为个人经验，希望能给大家一个参考，也希望大家多多支持我们。

原文链接：https://blog.csdn.net/cuixinzhou/article/details/93379130