请求代理转发(四)

请求代理转发(四)

请求代理转发(四)

使用 webclient 代理请求和支持文件上传

代理 Api

@Slf4j
@RestController
public class ProxyApi {private WebClient.Builder builder = WebClient.builder();public WebClient client() {return Webclient.create();}private static final String CLIENT_RESPONSE_ATTR = "CLIENT_RESPONSE_ATTR";private static final String PERCENTAGE_SIGN = "%";//目标服务器@Value("${hq.host:http://localhost:7777}")private String host;private static final String prefix = "/proxy";@RequestMapping(prefix + "/**")public Mono<Void> proxy(ServerWebExchange exchange) {URI requestUrl = rebuildURI(exchange);log.info(">>>>> proxy url: {}", requestUrl);ServerHttpRequest request = exchange.getRequest();HttpMethod method = request.getMethod();WebClient.RequestBodySpec bodySpec = client().method(method).uri(requestUrl).headers(httpHeaders -> {httpHeaders.addAll(exchange.getRequest().getHeaders());httpHeaders.remove("Host");});if (isUploadRequest(request)) {//处理上传return exchange.getMultipartData().flatMap(mmp -> {WebClient.RequestHeadersSpec<?> headersSpec = bodySpec.body(BodyInserters.fromMultipartData(mmp));return doProxy(exchange, headersSpec);});}WebClient.RequestHeadersSpec<?> headersSpec;if (requiresBody(method)) {headersSpec = bodySpec.body(BodyInserters.fromDataBuffers(request.getBody()));} else {headersSpec = bodySpec;}return doProxy(exchange, headersSpec);}private static boolean isUploadRequest(ServerHttpRequest request) {return request.getHeaders().getContentType() != null && request.getHeaders().getContentType().equalsTypeAndSubtype(MediaType.MULTIPART_FORM_DATA);}public Mono<? extends Void> doProxy(ServerWebExchange exchange, WebClient.RequestHeadersSpec<?> headersSpec) {return headersSpec.exchange().log().flatMap(clientResponse -> {ServerHttpResponse response = exchange.getResponse();response.setStatusCode(clientResponse.statusCode());response.getHeaders().setContentType(MediaType.APPLICATION_JSON_UTF8);exchange.getAttributes().put(CLIENT_RESPONSE_ATTR, clientResponse);return Mono.justOrEmpty(1);}).flatMap(a -> {ClientResponse clientResponse = exchange.getAttribute(CLIENT_RESPONSE_ATTR);if (clientResponse == null) {return Mono.empty();}ServerHttpResponse response = exchange.getResponse();return clientResponse.bodyToMono(String.class).flatMap(str -> {try {log.info(">>>>>>>> response {}", str);//自定义返回jsonDataBuffer wrap = response.bufferFactory().wrap(str.getBytes(StandardCharsets.UTF_8));return response.writeWith(Mono.just(wrap));} catch (Exception e) {return Mono.error(e);}});});}private URI rebuildURI(ServerWebExchange exchange) {URI original = exchange.getRequest().getURI();String path = path(prefix, exchange);URI uri = URI.create(host);//这个方式可以 copy get 请求的参数return UriComponentsBuilder.fromUri(original).scheme(uri.getScheme()).host(uri.getHost()).port(uri.getPort()).replacePath(path).build(containsEncodedParts(original)).toUri();}/*** @param prefix* @param exchange* @return*/private String path(String prefix, ServerWebExchange exchange) {//获取 完整的请求 urlString path = exchange.getRequest().getURI().getPath();return path.substring(prefix.length());}private boolean requiresBody(HttpMethod method) {switch (method) {case PUT:case POST:case PATCH:return true;default:return false;}}public static boolean containsEncodedParts(URI uri) {boolean encoded = (uri.getRawQuery() != null && uri.getRawQuery().contains(PERCENTAGE_SIGN))|| (uri.getRawPath() != null && uri.getRawPath().contains(PERCENTAGE_SIGN));if (encoded) {try {UriComponentsBuilder.fromUri(uri).build(true);return true;} catch (IllegalArgumentException ignored) {if (log.isTraceEnabled()) {log.trace("Error in containsEncodedParts", ignored);}}return false;}return encoded;}
}

服务api:

@PostMapping(value = "/body")
public Mono<R<String>> body(@RequestBody String name) {log.info("name: {}", name);return Mono.just(R.ok("success"));
}@PostMapping(value = "/form")
public Mono<R<String>> form(String name) {log.info("name: {}", name);return Mono.just(R.ok("success"));
}@RequestMapping(value = "/get")
public Mono<R<String>> get(String name) {log.info("name: {}", name);return Mono.just(R.ok("success"));
}@PostMapping(value = "/upload")
public Mono<R<String>> index(@RequestPart("file") FilePart filePart,ServerWebExchange exchange) throws IOException {System.out.println(filePart.filename());Path file = Files.createFile(Paths.get("test".concat(filePart.filename())));filePart.transferTo(file.toFile());return Mono.just(R.ok("success"));
}

good luck!