SpringCloud Gateway 获取 request body response write

话不多说,直接上码

/**
 * @author liuhanling
 * @create 2018-12-14 20:01
 * @desc
 */
@Slf4j
@Component
public class RequestBodyFilter implements GatewayFilter, Ordered {

    private static final String CACHE_REQUEST_BODY_OBJECT_KEY = "cachedRequestBodyObject";

    @Override
    @SuppressWarnings("unchecked")
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

        Class inClass = String.class;

        ServerRequest serverRequest = new DefaultServerRequest(exchange);
        ServerHttpRequest request = exchange.getRequest();

        //只记录 http 请求(包含 https)
        String schema = request.getURI().getScheme();
        if ((!"http".equals(schema) && !"https".equals(schema))) {
            return chain.filter(exchange);
        }

        String contentType = request.getHeaders().getFirst("Content-Type");
        String upload = request.getHeaders().getFirst("upload");

        //get 方法获取参数
        if ("GET".equals(request.getMethod().name())) {
            if (!request.getQueryParams().isEmpty()) {
                Map<String, String> map = new HashMap<>();
                request.getQueryParams().toSingleValueMap().forEach((key, val) -> map.put(key, getURLDecoder(val)));
                String param = new Gson().toJson(map);
                exchange.getAttributes().put(CACHE_REQUEST_BODY_OBJECT_KEY, param);
            }
            return chain.filter(exchange);
        }

        //没有内容类型不读取body
        if (contentType == null || contentType.length() == 0) {
            return chain.filter(exchange);
        }

        //文件上传不读取body
        if ("true".equals(upload)) {
            return chain.filter(exchange);
        }

        Mono<?> modifiedBody = serverRequest.bodyToMono(inClass).flatMap(o -> {
            log.debug("requestBody:{}", o);
            exchange.getAttributes().put(CACHE_REQUEST_BODY_OBJECT_KEY, o);
            return Mono.justOrEmpty(o);
        });

        BodyInserter bodyInserter = BodyInserters.fromPublisher(modifiedBody, inClass);
        HttpHeaders headers = new HttpHeaders();
        headers.putAll(exchange.getRequest().getHeaders());

        CachedBodyOutputMessage outputMessage = new CachedBodyOutputMessage(exchange, headers);
        return bodyInserter.insert(outputMessage, new BodyInserterContext())
                .then(Mono.defer(() -> {
                    ServerHttpRequestDecorator decorator = new ServerHttpRequestDecorator(exchange.getRequest()) {

                        @Override
                        public HttpHeaders getHeaders() {
                            long contentLength = headers.getContentLength();
                            HttpHeaders httpHeaders = new HttpHeaders();
                            httpHeaders.putAll(super.getHeaders());
                            if (contentLength > 0) {
                                httpHeaders.setContentLength(contentLength);
                            } else {
                                // TODO: this causes a 'HTTP/1.1 411 Length Required' on httpbin.org
                                httpHeaders.set(HttpHeaders.TRANSFER_ENCODING, "chunked");
                            }
                            return httpHeaders;
                        }

                        @Override
                        public Flux<DataBuffer> getBody() {
                            return outputMessage.getBody();
                        }
                    };
                    return chain.filter(exchange.mutate().request(decorator).build());
                }));
    }

    @Override
    public int getOrder() {
        return 0;
    }

    /**
     * URL 转码
     * @param val
     * @return
     */
    private String getURLDecoder(String val){
        try{
            return URLDecoder.decode(val, "utf-8");
        }catch (Exception e){
            log.error("getURLDecoder error",e);
        }
        return val;
    }
}

重写 ResponseBody

/**
 * @author liuhanling
 * @create 2018-12-27 10:39
 * @desc
 */
@Component
@Slf4j
public class ResponseBodyFilter implements GatewayFilter, Ordered {

    @Override
    @SuppressWarnings("unchecked")
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpResponseDecorator responseDecorator = new ServerHttpResponseDecorator(exchange.getResponse()) {

            @Override
            public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {

                Class inClass = String.class;
                Class outClass = String.class;

                String originalResponseContentType = exchange.getAttribute(ORIGINAL_RESPONSE_CONTENT_TYPE_ATTR);
                HttpHeaders httpHeaders = new HttpHeaders();
                //explicitly add it in this way instead of 'httpHeaders.setContentType(originalResponseContentType)'
                //this will prevent exception in case of using non-standard media types like "Content-Type: image"
                httpHeaders.add(HttpHeaders.CONTENT_TYPE, originalResponseContentType);
                ResponseAdapter responseAdapter = new ResponseAdapter(body, httpHeaders);
                DefaultClientResponse clientResponse = new DefaultClientResponse(responseAdapter, ExchangeStrategies.withDefaults());

                //TODO: flux or mono
                Mono modifiedBody = clientResponse.bodyToMono(inClass)
                        .flatMap(originalBody -> {
                            //如果是文件
                            Gson gson = new Gson();
                            Map<String,String> res = gson.fromJson(String.valueOf(originalBody),new TypeToken<HashMap<String, String>>() {}.getType());
                            //修改
                            res.put("test_id",UUID.randomUUID().toString().replace("-",""));
                            return Mono.just(gson.toJson(res));
                        });

                BodyInserter bodyInserter = BodyInserters.fromPublisher(modifiedBody, outClass);
                CachedBodyOutputMessage outputMessage = new CachedBodyOutputMessage(exchange, exchange.getResponse().getHeaders());
                return bodyInserter.insert(outputMessage, new BodyInserterContext())
                        .then(Mono.defer(() -> {
                            Flux<DataBuffer> messageBody = outputMessage.getBody();
                            //TODO: if (inputStream instanceof Mono) {
                            HttpHeaders headers = getDelegate().getHeaders();
                            if (!headers.containsKey(HttpHeaders.TRANSFER_ENCODING)) {
                                messageBody = messageBody.doOnNext(data -> headers.setContentLength(data.readableByteCount()));
                            }
                            // }
                            //TODO: use isStreamingMediaType?
                            return getDelegate().writeWith(messageBody);
                        }));
            }

            @Override
            public Mono<Void> writeAndFlushWith(Publisher<? extends Publisher<? extends DataBuffer>> body) {
                return writeWith(Flux.from(body)
                        .flatMapSequential(p -> p));
            }
        };

        return chain.filter(exchange.mutate().response(responseDecorator).build());
    }

    @Override
    public int getOrder() {
        return 0;
    }

    public class ResponseAdapter implements ClientHttpResponse {

        private final Flux<DataBuffer> flux;
        private final HttpHeaders headers;

        public ResponseAdapter(Publisher<? extends DataBuffer> body, HttpHeaders headers) {
            this.headers = headers;
            if (body instanceof Flux) {
                flux = (Flux) body;
            } else {
                flux = ((Mono)body).flux();
            }
        }

        @Override
        public Flux<DataBuffer> getBody() {
            return flux;
        }

        @Override
        public HttpHeaders getHeaders() {
            return headers;
        }

        @Override
        public HttpStatus getStatusCode() {
            return null;
        }

        @Override
        public int getRawStatusCode() {
            return 0;
        }

        @Override
        public MultiValueMap<String, ResponseCookie> getCookies() {
            return null;
        }
    }
}

版本信息

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Finchley.SR2</spring-cloud.version>
    </properties>

理论部分参考: https://blog.51cto.com/thinklili/2329184

来源：51CTO

作者：liuhanling

链接：https://blog.51cto.com/5634409/2343489