基于spring gateway 的静态资源缓存实现

由于子项目比较多，子项目都是通过嵌套的方式实现的。就会导致子页面加载比较慢，影响客户体验

实现思路（AI搜的--!）:

1、通过spring boot缓存实现静态资源缓存

2、在gateway过滤器，对静态资源进行缓存

直接上代码：

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-cache</artifactId>
</dependency>

package com.xxx.filter;import lombok.extern.slf4j.Slf4j;
import org.springframework.cache.Cache;
import org.springframework.cache.CacheManager;
import org.springframework.cache.support.SimpleValueWrapper;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.reactive.function.client.WebClient;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;import java.net.URI;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;/*** @author Wang* 创建时间: 2023/11/15 10:19* 功能描述：静态资源缓存*/
@Slf4j
@Component
public class StaticResourceFilter implements GlobalFilter, Ordered {private static final String STATIC_RESOURCE_PATTERN = "\\.(html|css|js|png|jpg|jpeg|gif|woff2|woff)$";private final WebClient webClient;private final CacheManager cacheManager;List<String> synchronizedList = Collections.synchronizedList(new ArrayList<>());public StaticResourceFilter(WebClient webClient, CacheManager cacheManager) {this.webClient = webClient;this.cacheManager = cacheManager;}@Overridepublic Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {ServerHttpRequest request = exchange.getRequest();URI uriInfo = request.getURI();String staticResourcePath = getUrl(uriInfo);if (isStaticResource(staticResourcePath) && !synchronizedList.contains(staticResourcePath)) {//Route route = exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_ROUTE_ATTR);String cacheKey = request.getURI().toString();Cache cache = cacheManager.getCache("staticResources");// 尝试从缓存中获取静态资源Object cachedResource = cache.get(cacheKey);if (cachedResource != null) {if (cachedResource instanceof SimpleValueWrapper) {cachedResource = ((SimpleValueWrapper) cachedResource).get();}// 如果缓存中存在，直接返回缓存的资源ServerHttpResponse response = exchange.getResponse();HttpHeaders headers = response.getHeaders();String fileSuffix = staticResourcePath.replaceAll(".*(\\.[a-zA-Z0-9]+)$", "$1");// 根据文件后缀设置MIME类型switch (fileSuffix) {case ".html":headers.setContentType(MediaType.TEXT_HTML);break;case ".js":headers.set(HttpHeaders.CONTENT_TYPE, "application/javascript");break;case ".css":headers.set(HttpHeaders.CONTENT_TYPE, "text/css");break;case ".png":headers.setContentType(MediaType.IMAGE_PNG);break;case ".jpg":case ".jpeg":headers.setContentType(MediaType.IMAGE_JPEG);break;case ".woff":headers.set(HttpHeaders.CONTENT_TYPE, "application/font-woff");break;case ".woff2":headers.set(HttpHeaders.CONTENT_TYPE, "application/font-woff2");break;case ".ttf":headers.set(HttpHeaders.CONTENT_TYPE, "application/x-font-ttf");break;case ".eot":headers.set(HttpHeaders.CONTENT_TYPE, "application/vnd.ms-fontobject");break;default:headers.setContentType(MediaType.ALL);break;}// 这里假设缓存的内容是字节数组，您可以根据实际情况进行调整DataBuffer dataBuffer = response.bufferFactory().wrap((byte[]) cachedResource);return response.writeWith(Mono.just(dataBuffer));}// 如果缓存不存在，则继续请求下游服务获取资源，并将其缓存起来return chain.filter(exchange).then(Mono.fromRunnable(() -> {getResourceFromDownstream(staticResourcePath, cacheKey, cache);}));}// 继续处理其他过滤器或请求return chain.filter(exchange);}@Overridepublic int getOrder() {return Ordered.HIGHEST_PRECEDENCE;}/*** 根据请求路径判断是否为静态资源请求** @param staticResourcePath 请求路径*/private boolean isStaticResource(String staticResourcePath) {Pattern pattern = Pattern.compile(STATIC_RESOURCE_PATTERN);Matcher matcher = pattern.matcher(staticResourcePath);return matcher.find();}/*** 请求下游服务静态资源的方法，这里只是一个示例，您需要根据实际情况实现此方法** @param cache              缓存* @param staticResourcePath URL* @param cacheKey           缓存Key*/private void getResourceFromDownstream(String staticResourcePath, String cacheKey, Cache cache) {synchronizedList.add(staticResourcePath);Mono<byte[]> mono = webClient.get().uri(staticResourcePath).retrieve().bodyToMono(byte[].class);// 处理响应数据mono.subscribe(res -> {synchronizedList.remove(staticResourcePath);cache.put(cacheKey, res);}, error -> {log.error("请求下游服务静态资源失败：{}，\n错误详情:{}", staticResourcePath, error.toString());});}/*** 获取静态资源地址** @param uri uri* @return 静态资源地址*/private String getUrl(URI uri) {String path = uri.getPath();String host = uri.getHost();int port = uri.getPort();// 下游服务的地址是String downstreamUrl = String.format("http://%s:%s%s", host, port, path);return downstreamUrl;}
}