java - 导致 POST 请求主体变空的过滤器

Question

我正在使用 HMAC 身份验证过滤器。当我访问我的 POST 请求正文时，在过滤器中，我能够在其中获取 XML。当我尝试访问 Controller 中的 XML 时，我得到一个空字符串。过滤器中的 xmlString 提供正确的 XML，但 Controller 中的 xmlString 提供空白字符串。我正在使用 Spring MVC。

我的过滤器是:

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest httpRequest = (HttpServletRequest) request;
        HttpServletResponse httpResponse = (HttpServletResponse) response;

        String authorisation = httpRequest.getHeader("authorization");
        String accessKeyId = authorisation.split(":")[0].split(" ")[1];
        String signature = authorisation.split(":")[1];
        String secretAccessKey = getSecretAccessKey(accessKeyId);

        InputStream xmlStream = httpRequest.getInputStream();
        String xmlString = IOUtils.toString(xmlStream, "UTF-8");
        String encodedXml = new String();
        try {
            encodedXml = HMACEncoder.calculateHMAC(xmlString, secretAccessKey);
        } catch (SignatureException e) {
            e.printStackTrace();
        }
        if (!signature.equals(encodedXml))
            httpResponse.sendError(HttpServletResponse.SC_UNAUTHORIZED);
        else
            chain.doFilter(request, response);
    }

我的 Controller 是:

@RequestMapping(value = "/user", method = RequestMethod.POST)
public String fetchUserString(HttpServletRequest request) {
    InputStream xml = null;
    String xmlString = null;
    try {
        xml = request.getInputStream();
        xmlString = IOUtils.toString(xml, "UTF-8");
    } catch (IOException e) {
        e.printStackTrace();
    }
    return xmlString;
}

Answer 1

正如 praki 所建议的，我将 XML 放在请求属性中，在我的 Controller 中，我从请求属性中获取它，然后将 XML 放在 ModelAttribute 中。这是我的代码:

我的过滤器:

@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
    HttpServletRequest httpRequest = (HttpServletRequest) request;
    HttpServletResponse httpResponse = (HttpServletResponse) response;
    if (httpRequest.getMethod().equalsIgnoreCase("POST")) {    
        String authorisation = httpRequest.getHeader("authorization");
        String accessKeyId = authorisation.split(":")[0].split(" ")[1];
        String signature = authorisation.split(":")[1];
        String secretAccessKey = getSecretAccessKey(accessKeyId);    
        ServletInputStream servletStream = httpRequest.getInputStream();
        String xmlString = IOUtils.toString(servletStream);
        String encodedXml = new String();
        try {
            encodedXml = HMACEncoder.calculateHMAC(xmlString, secretAccessKey);
        } catch (SignatureException e) {
            e.printStackTrace();
        }
        httpRequest.setAttribute("content", xmlString);
        if (!signature.equals(encodedXml))
            httpResponse.sendError(HttpServletResponse.SC_UNAUTHORIZED);
        else
            chain.doFilter(request, response);
    } else
        chain.doFilter(request, response);
}

和我的 Controller :

@RequestMapping(value = "/add", method = RequestMethod.POST, produces = "application/xml")
public @ResponseBody Catalog addCatalog(@ModelAttribute("catalog") Catalog catalog) {
    logger.info("In addCatalog with " + catalog);
    catalog.getHeader().setOrganizationId(IConstant.ORGANIZATION_ID_BSL);
    try {
        catalog = catalogService.addCatalogIntegration(catalog);
    } catch (Exception e) {
        e.printStackTrace();
    }
    logger.info("Returning from addCatalog with " + catalog);
    return catalog;
}

@ModelAttribute("catalog")
private Catalog getCatalog(HttpServletRequest request) throws Exception {
    Catalog catalog = new Catalog();
    try {
        String xml = (String) request.getAttribute("content");
        if (xml != null) {
            JAXBContext jaxbContext = JAXBContext.newInstance(Catalog.class);
            Unmarshaller unmarshaller = jaxbContext.createUnmarshaller();
            catalog = (Catalog) unmarshaller.unmarshal(new StringReader(xml));
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    return catalog;
}