gateway的作用是可以来作为服务的一个代理， 请求的转发，中间的一个路由的功能， 这就好比是nginx的功能；
相比较zuul, zuul是将请求结果代理转发到了当前eureka注册中心的其他的服务上去的， 局限在了本服务集群体系里面的服务调用了；
gateway有跟好的一个路由的功能；
本章的目的是为了记录gateway一些简单的使用， 内容参考了其他的博客， 自己实践一下；
@SpringBootApplication
@RestController
@EnableDiscoveryClient
public class GatewaySimpleApplication {
public static void main(String[] args) {
SpringApplication.run(GatewaySimpleApplication.class, args);
}
@Autowired
ConfigurableApplicationContext applicationContext;
@Bean
public RouteLocatorBuilder routeLocatorBuilder() {
return new RouteLocatorBuilder(applicationContext);
}
//全局的token的过滤器
@Bean
public TokenFilter tokenFilter() {
return new TokenFilter();
}
//自定义的resolver来给redis-rate-limiter使用
@Bean
public AddrKeyResolver addrKeyResolver(){
return new AddrKeyResolver();
}
@Bean
public UriKeyResolver uriKeyResolver(){
return new UriKeyResolver();
}
@Bean
public RouteLocator routeLocator(RouteLocatorBuilder builder) {
String httpUrl = "http://httpbin.org:80/get";
return builder.routes()
//路由的参数restfull请求
.route(r -> r.path("/foo/{segment}").uri(httpUrl).id("route_segment"))
//cookie参数
.route(r -> r.cookie("name", "java").uri(httpUrl).id("cookie_test"))
//header参数
.route(p -> p.path("/get").filters(f -> f.addRequestHeader("Hello", "World")).uri(httpUrl).id("header_param"))
//时间before
.route(r -> r.before(changeShanghaiToUTC("2020-01-01 11:11:11")).uri(httpUrl).id("before_time"))
//时间after
.route(r -> r.after(changeShanghaiToUTC("2018-01-01 11:11:11")).uri(httpUrl).id("after_time"))
//fallback
.route(p -> p.host("*.hystrix.com").filters(f -> f.hystrix(h -> h.setName("cmd").setFallbackUri("forward:/fallback"))).uri(httpUrl).id("fallback"))
//order越大优先级越低
.route(r -> r.path("/customer/**")
.filters(f -> f.filter(new RequestTimeFilter()).addRequestHeader("X-Response-Default-Foo", "Default-Foo"))
.uri(httpUrl).order(-1).id("customer_filter"))
.build();
}
/**
* 请求的时间计算的过滤器
*/
static class RequestTimeFilter implements GatewayFilter, Order {
private static final Logger logger = LoggerFactory.getLogger(RequestTimeFilter.class);
static String TEMP_KEY = "startTime";
@Override
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
exchange.getAttributes().put(TEMP_KEY, System.currentTimeMillis());
return chain.filter(exchange).then(Mono.fromRunnable(() -> {
Long startTime = exchange.getAttribute(TEMP_KEY);
if (null != startTime) {
logger.info(exchange.getRequest().getURI().getRawPath() + " : " + (System.currentTimeMillis() - startTime));
}
}));
}
@Override
public int value() {
return 0;
}
@Override
public Class<? extends Annotation> annotationType() {
return null;
}
}
/**
* token 全局的过滤器
*/
static class TokenFilter implements GlobalFilter, Order {
private static final Logger logger = LoggerFactory.getLogger(TokenFilter.class);
@Override
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
String token = exchange.getRequest().getQueryParams().getFirst("token");
if (StringUtils.isEmpty(token)) {
logger.info("token is empty...");
exchange.getResponse().setStatusCode(HttpStatus.UNAUTHORIZED);
return exchange.getResponse().setComplete();
}
return chain.filter(exchange);
}
@Override
public int value() {
return 0;
}
@Override
public Class<? extends Annotation> annotationType() {
return null;
}
}
static class AddrKeyResolver implements KeyResolver{
@Override
public Mono<String> resolve(ServerWebExchange exchange) {
return Mono.just(exchange.getRequest().getRemoteAddress().getAddress().getHostAddress());
}
}
static class UriKeyResolver implements KeyResolver{
@Override
public Mono<String> resolve(ServerWebExchange exchange) {
return Mono.just(exchange.getRequest().getURI().getPath());
}
}
public static ZonedDateTime changeShanghaiToUTC(String dateStr) {
DateTimeFormatter beijingFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss").withZone(ZoneId.of("Asia/Shanghai"));
if (StringUtils.isBlank(dateStr)) {
return null;
}
ZonedDateTime beijingDateTime = ZonedDateTime.parse(dateStr, beijingFormatter);
return beijingDateTime.withZoneSameInstant(ZoneId.of("UTC"));
}
/**全局的fallback*/
@RequestMapping("/fallback")
public Mono<String> fallback() {
System.out.println("fallback run...");
return Mono.just("fallback");
}
}
另外还有一种route是通过yaml来进行配置的， 无论是java config 还是 yaml配置都是可以的
描述：
limite_route，当请求http://localhost:8081/getMessages?messageID=2&token=222服务的时候会进行限流的动作
这就是redis-rate-limiter的使用， 之前一直是不生效，经过搜索无法找到正解， 最后查看日志发现走了其他的route,
route都是可以自定义id的， 我们可以区分当前的请求是结果了那个route , 不生效是因为这个route的优先级别不够被别的route限制性了；
解决办法：加入order =-1 或者进行路由path进行匹配精准一些；
hystrix_route是个请求hystrxy调用失败的测试
启用gateway的endpoint
