从HttpServletRequest获取XML并使用到endpoint

Question

我想从请求和响应中获得XML数据，并将其用于Rest控制器。我试过这个：

@RestController()
    public class HomeController {

        @PostMapping(value = "/v1")
      public Response handleMessage(@RequestBody Transaction transaction, HttpServletRequest request, HttpServletResponse response) throws Exception {

           HttpServletRequest request, HttpServletResponse response

            System.out.println("!!!!!!! InputStream");
            System.out.println(request.getInputStream());
            System.out.println(response.getOutputStream());

            InputStream in = request.getInputStream();
            String readLine;
            BufferedReader br = new BufferedReader(new InputStreamReader(in));

            while (((readLine = br.readLine()) != null)) {
                System.out.println(readLine);    
            }
         } 
    }

但我得到java.io.ioException:UT010029:Stream is closed

将内容转换成字符串变量的正确方法是什么？

@Component
public class HttpLoggingFilter implements Filter {

    private static final Logger logger = LoggerFactory.getLogger(HttpLoggingFilter.class);

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {

        ResettableStreamHttpServletRequest wrappedRequest = new ResettableStreamHttpServletRequest((HttpServletRequest) request);
        wrappedRequest.getInputStream().read();
        String body = IOUtils.toString(wrappedRequest.getReader());
        System.out.println("!!!!!!!!!!!!!!!!!! " + body);
        wrappedRequest.resetInputStream();


        chain.doFilter(request, response);
    }

    public class ResettableStreamHttpServletRequest extends HttpServletRequestWrapper {
        private byte[] rawData;
        private HttpServletRequest request;
        private ResettableServletInputStream servletStream;

        ResettableStreamHttpServletRequest(HttpServletRequest request) {
            super(request);
            this.request = request;
            this.servletStream = new ResettableServletInputStream();
        }

        void resetInputStream() {
            servletStream.stream = new ByteArrayInputStream(rawData);
        }

        @Override
        public ServletInputStream getInputStream() throws IOException {
            if (rawData == null) {
                rawData = IOUtils.toByteArray(this.request.getInputStream());
                servletStream.stream = new ByteArrayInputStream(rawData);
            }
            return servletStream;
        }

        @Override
        public BufferedReader getReader() throws IOException {
            if (rawData == null) {
                rawData = IOUtils.toByteArray(this.request.getInputStream());
                servletStream.stream = new ByteArrayInputStream(rawData);
            }
            String encoding = getCharacterEncoding();
            if (encoding != null) {
                return new BufferedReader(new InputStreamReader(servletStream, encoding));
            } else {
                return new BufferedReader(new InputStreamReader(servletStream));
            }
        }

        private class ResettableServletInputStream extends ServletInputStream {
            private InputStream stream;

            @Override
            public int read() throws IOException {
                return stream.read();
            }

            @Override
            public boolean isFinished() {
                // TODO Auto-generated method stub
                return false;
            }

            @Override
            public boolean isReady() {
                // TODO Auto-generated method stub
                return false;
            }

            @Override
            public void setReadListener(ReadListener readListener) {
                // TODO Auto-generated method stub

            }
        }
    }   
}

@RestController()
public class HomeController {

    @PostMapping(value = "/v1")
  public Response handleMessage(@RequestBody Transaction transaction, HttpServletRequest request, org.zalando.logbook.HttpRequest requestv, HttpServletResponse response) throws Exception {

       // Get here request and response and log it into DB
     } 
}

Answer 1

这里有一堆类来完成它。这是一个OncePerRequestFilter实现，请查看https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/web/filter/OncePerRequestFilter.html。基本上问题在于，在链式过滤器中，请求流和响应流只能读取一次。因此，需要将这两个流包装在可以多次读取的内容中。

在前两行中，我将request和response封装在requestToUse和responseTouse中。ResettableStreamHttpServletRequest和ResettableStreamHttpServletResponse是将原始字符串主体保存在其中的包装类，每次需要流时，它们都会返回一个新的流。

我从我做的一个老项目里拿来的。实际上有更多的包层，但我为你提取了主要部分。这可能不能立即编译。试试看，让我知道，我会帮助你使它发挥作用。

    public class RequestResponseLoggingFilter extends OncePerRequestFilter {

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
        //here you wrap the request and response into some resetable istream class
        HttpServletRequest requestToUse = new ResettableStreamHttpServletRequest(request);
        HttpServletResponse responseToUse = new ResettableStreamHttpServletResponse(response);

        //you read the request to log it
        byte[] payload = IOUtils.toByteArray(requestToUse.getReader(), requestToUse.getCharacterEncoding());      
        String body =  new String(payload, requestToUse.getCharacterEncoding());

        //here you log the body request
        log.(body);

        //let the chain continue
        filterChain.doFilter(requestToUse, responseToUse);

        // Here we log the response
        String response =  new String(responseToUse.toString().getBytes(), responseToUse.getCharacterEncoding());

        //since you can read the stream just once, you will need it again for chain to be able to continue, so you reset it
        ResettableStreamHttpServletResponse responseWrapper = WebUtils.getNativeResponse(responseToUse, ResettableStreamHttpServletResponse.class);
        if (responseWrapper != null) {
            responseWrapper.copyBodyToResponse(true);
        }
    }

}

    public class ResettableStreamHttpServletRequest extends HttpServletRequestWrapper {

    private byte[] rawData;
    private ResettableServletInputStream servletStream;

    public ResettableStreamHttpServletRequest(HttpServletRequest request) throws IOException {
        super(request);
        rawData = IOUtils.toByteArray(request.getInputStream());
        servletStream = new ResettableServletInputStream();
        servletStream.setStream(new ByteArrayInputStream(rawData));
    }

    @Override
    public ServletInputStream getInputStream() throws IOException {
        servletStream.setStream(new ByteArrayInputStream(rawData));
        return servletStream;
    }

    @Override
    public BufferedReader getReader() throws IOException {
        servletStream.setStream(new ByteArrayInputStream(rawData));
        return new BufferedReader(new InputStreamReader(servletStream));
    }

}

    public class ResettableStreamHttpServletResponse extends HttpServletResponseWrapper {

    private ByteArrayServletOutputStream byteArrayServletOutputStream = new ByteArrayServletOutputStream();

    public ResettableStreamHttpServletResponse(HttpServletResponse response) throws IOException {
        super(response);
    }

    /**
     * Copy the cached body content to the response.
     *
     * @param complete whether to set a corresponding content length for the complete cached body content
     * @since 4.2
     */
    public void copyBodyToResponse(boolean complete) throws IOException {
        byte[] array = byteArrayServletOutputStream.toByteArray();
        if (array.length > 0) {
            HttpServletResponse rawResponse = (HttpServletResponse) getResponse();
            if (complete && !rawResponse.isCommitted()) {
                rawResponse.setContentLength(array.length);
            }
            rawResponse.getOutputStream().write(byteArrayServletOutputStream.toByteArray());
            if (complete) {
                super.flushBuffer();
            }
        }
    }

    /**
     * The default behavior of this method is to return getOutputStream() on the wrapped response object.
     */
    @Override
    public ServletOutputStream getOutputStream() throws IOException {
        return byteArrayServletOutputStream;
    }

    /**
     * The default behavior of this method is to return getOutputStream() on the wrapped response object.
     */
    @Override
    public String toString() {
        String response = new String(byteArrayServletOutputStream.toByteArray());
        return response;
    }

}