Spring REST服务:从请求中检索JSON

Question

我正在Spring 3.1上构建REST服务。我正在为此使用@EnableWebMVC注释。由于我的服务将只接受JSON请求，因此我还希望将传入请求转储到MongoDB集合中以进行日志记录（以及稍后的数据转换）。我想访问原始的JSON请求（我可以在非Spring实现上使用“@Content HttpServletRequest request”作为方法参数来执行此操作）。

我是Spring新手。因此，请帮助我提供实现这一目标的方向。谢谢！

更新：问题尚未完全解决。只有我对GET的测试有效。它在POST中失败。因此未选中已接受的答案

问题是，即使我创建了一个HttpServletRequestWrapper，我也无法在处理和包装请求之后转发请求。以下是发生的情况：

拦截器:

public class DBLogInterceptor extends HandlerInterceptorAdapter {
    MyRequestWrapper requestWrapper;

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

    @Override
    public boolean preHandle(
            HttpServletRequest request,
            HttpServletResponse response,
            Object handler) throws Exception 
    {
        requestWrapper = new MyRequestWrapper(request);
        // Code removed, but it just dumps requestWrapper.getBody() into DB
        return super.preHandle(requestWrapper, response, handler);
    }
}

HTTP POST 服务方法

@RequestMapping(method = RequestMethod.POST, consumes="application/json", produces="application/json", value = "employee")
@ResponseBody
public String updateEntity(@RequestBody Employee emp) {
    // Do some DB Stuff. Anyway, the control flow does not reach this place.
    return "Employee " + emp.getName() + " updated successfully!";
}

现在，每当我发送邮件时，都会出现异常：

12:04:53,821 DEBUG DBLogInterceptor:22 - {"name":"Van Damme","dept":"Applied Martial Arts"}
12:04:53,843 DEBUG RequestResponseBodyMethodProcessor:117 - Reading [com.test.webapp.login.domain.Employee] as "application/json" using [org.springframework.http.converter.json.MappingJacksonHttpMessageConverter@154174f9]
12:04:53,850 DEBUG ExceptionHandlerExceptionResolver:132 - Resolving exception from handler [public java.lang.String com.test.webapp.controller.EmployeeService.updateEntity(com.test.webapp.login.domain.Employee)]: java.io.IOException: Stream closed
12:04:53,854 DEBUG ResponseStatusExceptionResolver:132 - Resolving exception from handler [public java.lang.String com.test.webapp.controller.EmployeeService.updateEntity(com.test.webapp.login.domain.Employee)]: java.io.IOException: Streamclosed
12:04:53,854 DEBUG DefaultHandlerExceptionResolver:132 - Resolving exception from handler [public java.lang.String com.test.webapp.controller.EmployeeService.updateEntity(com.test.webapp.login.domain.Employee)]: java.io.IOException: Streamclosed
12:04:53,859 DEBUG DispatcherServlet:910 - Could not complete request
java.io.IOException: Stream closed
        at org.apache.catalina.connector.InputBuffer.read(InputBuffer.java:312)
        at org.apache.catalina.connector.CoyoteInputStream.read(CoyoteInputStream.java:200)
        at org.codehaus.jackson.impl.ByteSourceBootstrapper.ensureLoaded(ByteSourceBootstrapper.java:507)
        at org.codehaus.jackson.impl.ByteSourceBootstrapper.detectEncoding(ByteSourceBootstrapper.java:129)
        at org.codehaus.jackson.impl.ByteSourceBootstrapper.constructParser(ByteSourceBootstrapper.java:224)
        at org.codehaus.jackson.JsonFactory._createJsonParser(JsonFactory.java:785)
        at org.codehaus.jackson.JsonFactory.createJsonParser(JsonFactory.java:561)
        at org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1914)
        at org.springframework.http.converter.json.MappingJacksonHttpMessageConverter.readInternal(MappingJacksonHttpMessageConverter.java:124)
        at org.springframework.http.converter.AbstractHttpMessageConverter.read(AbstractHttpMessageConverter.java:153)
        at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodArgumentResolver.readWithMessageConverters(AbstractMessageConverterMethodArgumentResolver.java:120)
        at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodArgumentResolver.readWithMessageConverters(AbstractMessageConverterMethodArgumentResolver.java:91)
        at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.resolveArgument(RequestResponseBodyMethodProcessor.java:71)
        at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:75)
        at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:156)
        at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:117)
        at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:96)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:617)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:578)
        at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)
        at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:789)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:999)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:565)
        at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:307)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)

我期望HttpServletRequestWrapper负责缓存请求。但这不会以某种方式发生。

Answer 1

我知道这是一个老问题，但对于那些仍在寻找解决方案的人来说，这对我有用：

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.Collection;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletInputStream;
import javax.servlet.ServletOutputStream;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.io.output.TeeOutputStream;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

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 {
        try {
            HttpServletRequest httpServletRequest = (HttpServletRequest) request;
            HttpServletResponse httpServletResponse = (HttpServletResponse) response;

            Map<String, String> requestMap = this
                    .getTypesafeRequestMap(httpServletRequest);
            BufferedRequestWrapper bufferedRequest = new BufferedRequestWrapper(
                    httpServletRequest);
            BufferedResponseWrapper bufferedResponse = new BufferedResponseWrapper(
                    httpServletResponse);

            final StringBuilder logMessage = new StringBuilder(
                    "REST Request - ").append("[HTTP METHOD:")
                    .append(httpServletRequest.getMethod())
                    .append("] [PATH INFO:")
                    .append(httpServletRequest.getPathInfo())
                    .append("] [REQUEST PARAMETERS:").append(requestMap)
                    .append("] [REQUEST BODY:")
                    .append(bufferedRequest.getRequestBody())
                    .append("] [REMOTE ADDRESS:")
                    .append(httpServletRequest.getRemoteAddr()).append("]");

            chain.doFilter(bufferedRequest, bufferedResponse);
            logMessage.append(" [RESPONSE:")
                    .append(bufferedResponse.getContent()).append("]");
            logger.debug(logMessage.toString());
        } catch (Throwable a) {
            logger.error(a.getMessage());
        }
    }

    private Map<String, String> getTypesafeRequestMap(HttpServletRequest request) {
        Map<String, String> typesafeRequestMap = new HashMap<String, String>();
        Enumeration<?> requestParamNames = request.getParameterNames();
        while (requestParamNames.hasMoreElements()) {
            String requestParamName = (String) requestParamNames.nextElement();
            String requestParamValue = request.getParameter(requestParamName);
            typesafeRequestMap.put(requestParamName, requestParamValue);
        }
        return typesafeRequestMap;
    }

    @Override
    public void destroy() {
    }

    private static final class BufferedRequestWrapper extends
            HttpServletRequestWrapper {

        private ByteArrayInputStream bais = null;
        private ByteArrayOutputStream baos = null;
        private BufferedServletInputStream bsis = null;
        private byte[] buffer = null;

        public BufferedRequestWrapper(HttpServletRequest req)
                throws IOException {
            super(req);
            // Read InputStream and store its content in a buffer.
            InputStream is = req.getInputStream();
            this.baos = new ByteArrayOutputStream();
            byte buf[] = new byte[1024];
            int read;
            while ((read = is.read(buf)) > 0) {
                this.baos.write(buf, 0, read);
            }
            this.buffer = this.baos.toByteArray();
        }

        @Override
        public ServletInputStream getInputStream() {
            this.bais = new ByteArrayInputStream(this.buffer);
            this.bsis = new BufferedServletInputStream(this.bais);
            return this.bsis;
        }

        String getRequestBody() throws IOException {
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    this.getInputStream()));
            String line = null;
            StringBuilder inputBuffer = new StringBuilder();
            do {
                line = reader.readLine();
                if (null != line) {
                    inputBuffer.append(line.trim());
                }
            } while (line != null);
            reader.close();
            return inputBuffer.toString().trim();
        }

    }

    private static final class BufferedServletInputStream extends
            ServletInputStream {

        private ByteArrayInputStream bais;

        public BufferedServletInputStream(ByteArrayInputStream bais) {
            this.bais = bais;
        }

        @Override
        public int available() {
            return this.bais.available();
        }

        @Override
        public int read() {
            return this.bais.read();
        }

        @Override
        public int read(byte[] buf, int off, int len) {
            return this.bais.read(buf, off, len);
        }

    }

    public class TeeServletOutputStream extends ServletOutputStream {

        private final TeeOutputStream targetStream;

        public TeeServletOutputStream(OutputStream one, OutputStream two) {
            targetStream = new TeeOutputStream(one, two);
        }

        @Override
        public void write(int arg0) throws IOException {
            this.targetStream.write(arg0);
        }

        public void flush() throws IOException {
            super.flush();
            this.targetStream.flush();
        }

        public void close() throws IOException {
            super.close();
            this.targetStream.close();
        }
    }

    public class BufferedResponseWrapper implements HttpServletResponse {

        HttpServletResponse original;
        TeeServletOutputStream tee;
        ByteArrayOutputStream bos;

        public BufferedResponseWrapper(HttpServletResponse response) {
            original = response;
        }

        public String getContent() {
            return bos.toString();
        }

        public PrintWriter getWriter() throws IOException {
            return original.getWriter();
        }

        public ServletOutputStream getOutputStream() throws IOException {
            if (tee == null) {
                bos = new ByteArrayOutputStream();
                tee = new TeeServletOutputStream(original.getOutputStream(),
                        bos);
            }
            return tee;

        }

        @Override
        public String getCharacterEncoding() {
            return original.getCharacterEncoding();
        }

        @Override
        public String getContentType() {
            return original.getContentType();
        }

        @Override
        public void setCharacterEncoding(String charset) {
            original.setCharacterEncoding(charset);
        }

        @Override
        public void setContentLength(int len) {
            original.setContentLength(len);
        }

        @Override
        public void setContentType(String type) {
            original.setContentType(type);
        }

        @Override
        public void setBufferSize(int size) {
            original.setBufferSize(size);
        }

        @Override
        public int getBufferSize() {
            return original.getBufferSize();
        }

        @Override
        public void flushBuffer() throws IOException {
            tee.flush();
        }

        @Override
        public void resetBuffer() {
            original.resetBuffer();
        }

        @Override
        public boolean isCommitted() {
            return original.isCommitted();
        }

        @Override
        public void reset() {
            original.reset();
        }

        @Override
        public void setLocale(Locale loc) {
            original.setLocale(loc);
        }

        @Override
        public Locale getLocale() {
            return original.getLocale();
        }

        @Override
        public void addCookie(Cookie cookie) {
            original.addCookie(cookie);
        }

        @Override
        public boolean containsHeader(String name) {
            return original.containsHeader(name);
        }

        @Override
        public String encodeURL(String url) {
            return original.encodeURL(url);
        }

        @Override
        public String encodeRedirectURL(String url) {
            return original.encodeRedirectURL(url);
        }

        @SuppressWarnings("deprecation")
        @Override
        public String encodeUrl(String url) {
            return original.encodeUrl(url);
        }

        @SuppressWarnings("deprecation")
        @Override
        public String encodeRedirectUrl(String url) {
            return original.encodeRedirectUrl(url);
        }

        @Override
        public void sendError(int sc, String msg) throws IOException {
            original.sendError(sc, msg);
        }

        @Override
        public void sendError(int sc) throws IOException {
            original.sendError(sc);
        }

        @Override
        public void sendRedirect(String location) throws IOException {
            original.sendRedirect(location);
        }

        @Override
        public void setDateHeader(String name, long date) {
            original.setDateHeader(name, date);
        }

        @Override
        public void addDateHeader(String name, long date) {
            original.addDateHeader(name, date);
        }

        @Override
        public void setHeader(String name, String value) {
            original.setHeader(name, value);
        }

        @Override
        public void addHeader(String name, String value) {
            original.addHeader(name, value);
        }

        @Override
        public void setIntHeader(String name, int value) {
            original.setIntHeader(name, value);
        }

        @Override
        public void addIntHeader(String name, int value) {
            original.addIntHeader(name, value);
        }

        @Override
        public void setStatus(int sc) {
            original.setStatus(sc);
        }

        @SuppressWarnings("deprecation")
        @Override
        public void setStatus(int sc, String sm) {
            original.setStatus(sc, sm);
        }

        @Override
        public String getHeader(String arg0) {
            return original.getHeader(arg0);
        }

        @Override
        public Collection<String> getHeaderNames() {
            return original.getHeaderNames();
        }

        @Override
        public Collection<String> getHeaders(String arg0) {
            return original.getHeaders(arg0);
        }

        @Override
        public int getStatus() {
            return original.getStatus();
        }

    }
}

然后简单地在web.xml注册过滤器，你就完成了。所有信用：http://wetfeetblog.com/servlet-filer-to-log-request-and-response-details-and-payload/431（我只是做了一些小的修复）。

Answer 2

我怀疑HttpServletRequest estWrapper是否可以工作...看看DispatcherServlet实现：

            HandlerInterceptor[] interceptors = mappedHandler.getInterceptors();
            if (interceptors != null) {
                for (int i = 0; i < interceptors.length; i++) {
                    HandlerInterceptor interceptor = interceptors[i];
                    if (!interceptor.preHandle(processedRequest, response, mappedHandler.getHandler())) {
                        triggerAfterCompletion(mappedHandler, interceptorIndex, processedRequest, response, null);
                        return;
                    }
                    interceptorIndex = i;
                }
            }

            // Actually invoke the handler.
            mv = ha.handle(processedRequest, response, mappedHandler.getHandler());

它仍然传递对“processedRequest”的引用，该引用引用了流已被读取的HttpServletRequest请求。

Answer 3

使用HttpServletRequest对象，您可以访问客户端用于发出请求的URL、使用的方法（get、POST、PUT等）、查询字符串和标题。

获取RequestBody可能有点棘手，可能需要使用HttpServletRequestWrapper对象。由于请求体只能读取一次，因此您需要扩展包装器来访问它，以便您的目标控制器稍后仍然可以访问它，将JSON反序列化为POJO对象。

public class MyRequestWrapper extends HttpServletRequestWrapper {
 private final String body;
 public MyRequestWrapper(HttpServletRequest request) throws IOException {
   super(request);
   StringBuilder stringBuilder = new StringBuilder();
   BufferedReader bufferedReader = null;
   try {
     InputStream inputStream = request.getInputStream();
     if (inputStream != null) {
       bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
       char[] charBuffer = new char[128];
       int bytesRead = -1;
       while ((bytesRead = bufferedReader.read(charBuffer)) > 0) {
         stringBuilder.append(charBuffer, 0, bytesRead);
       }
     } else {
       stringBuilder.append("");
     }
   } catch (IOException ex) {
       throw ex;
   } finally {
     if (bufferedReader != null) {
       try {
         bufferedReader.close();
       } catch (IOException ex) {
         throw ex;
       }
     }
   }
   body = stringBuilder.toString();
 }

 @Override
 public ServletInputStream getInputStream() throws IOException {
   final ByteArrayInputStream byteArrayInputStream = new     ByteArrayInputStream(body.getBytes());
   ServletInputStream servletInputStream = new ServletInputStream() {
     public int read() throws IOException {
       return byteArrayInputStream.read();
     }
   };
   return servletInputStream;
 }

 @Override
 public BufferedReader getReader() throws IOException {
   return new BufferedReader(new InputStreamReader(this.getInputStream()));
 }

 public String getBody() {
   return this.body;
 }
}

要访问中心位置的请求，可以使用过滤器或Spring拦截器。这两个都是在请求被委托给控制器之前调用的，并且都可以访问servlet。

下面是一个使用Spring拦截器的实际日志示例:

package com.vaannila.interceptor;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.log4j.BasicConfigurator;
import org.apache.log4j.Logger;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler. HandlerInterceptorAdapter;

public class LoggerInterceptor extends HandlerInterceptorAdapter {
    static Logger logger = Logger.getLogger(LoggerInterceptor.class);

    static {
        BasicConfigurator.configure();
    }

    @Override

    public boolean preHandle(HttpServletRequest request,
        HttpServletResponse response, Object handler) throws Exception {

        logger.info("Before handling the request");
        return super.preHandle(request, response, handler);
    }

    @Override
    public void postHandle(HttpServletRequest request,
        HttpServletResponse response, Object handler,
            ModelAndView modelAndView) throws Exception {

        logger.info("After handling the request");
        super.postHandle(request, response, handler, modelAndView);
    }

    @Override
    public void afterCompletion(HttpServletRequest request,
        HttpServletResponse response, Object handler, Exception ex)
            throws Exception {

        logger.info("After rendering the view");
        super.afterCompletion(request, response, handler, ex);
    }
}


<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:p="http://www.springframework.org/schema/p"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="viewResolver" class="org.springframework.web.servlet.view.    InternalResourceViewResolver" p:prefix="/WEB-INF/jsp/" p:suffix=".jsp" />

    <bean id="handlerMapping" class="org.springframework.web.servlet.handler. BeanNameUrlHandlerMapping" p:interceptors-ref="loggerInterceptor" />

    <bean id="loggerInterceptor" class="com.vaannila.interceptor.LoggerInterceptor" />

    <bean id="userService" class="com.vaannila.service.UserServiceImpl" />

    <bean name="/userRegistration.htm" class="com.vaannila.web.UserController" p:userService-ref="userService" p:formView="userForm" p:successView="userSuccess" />

</beans>

在 LoggerInterceptor 中，可以使用以下代码来访问请求：

MyRequestWrapper myRequestWrapper = new MyRequestWrapper((HttpServletRequest) request);

String body = myRequestWrapper.getBody();
String clientIP = myRequestWrapper.getRemoteHost();
int clientPort = request.getRemotePort();
String uri = myRequestWrapper.getRequestURI();

System.out.println(body);
System.out.println(clientIP);
System.out.println(clientPort);
System.out.println(uri);