Spring/SpringBoot 过滤器/拦截器获取http 请求request中的参数和 response返回值

左手的ㄟ右手 2021-09-20 00:34 1090阅读 0赞

## 需求：每个接口被调用时，获取接口的请求参数及返回值，进行保存 ##

参考：  
[https://www.jianshu.com/p/69c6fba08c92][https_www.jianshu.com_p_69c6fba08c92]  
[https://blog.csdn.net/qq\_33206732/article/details/78623042][https_blog.csdn.net_qq_33206732_article_details_78623042]  
思考：  
1.request 和 response 中的数据都是 存在流中的（缓存中）获取一次就没有了，需要重新写回去。  
2.通过拦截器 获取，但是拦截器中获取不到 response 的返回值  
3.通过 实现 RequestBodyAdvice和ResponseBodyAdvice两个接口 进行操作，很方便，但是我不会。。。我觉得 这是两个类，很难同时保存一个请求中的请求参数和返回值  
4.最后决定用 filter 实现。  
首先需要 继承HttpServletRequestWrapper 和 HttpServletResponseWrapper 两个包装类对 request和response进行包装，从中获取数据，代码整理如下。  
（我是新人，不知道怎么写，直接看代码吧 -.-！）

package com.hoau.psb.servlet;
    
    import javax.servlet.ReadListener;
    import javax.servlet.ServletInputStream;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletRequestWrapper;
    import java.io.*;
    
    public class RequestWrapper extends HttpServletRequestWrapper { 
        private final String body;
    
        public RequestWrapper(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 boolean isFinished() { 
                    return false;
                }
    
                public boolean isReady() { 
                    return false;
                }
    
                public void setReadListener(ReadListener readListener) { 
                }
    
                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;
        }
    
    }

package com.hoau.psb.servlet;
    
    import javax.servlet.ServletOutputStream;
    import javax.servlet.WriteListener;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.http.HttpServletResponseWrapper;
    import java.io.*;
    
    /** * @param * @author * @create 2019-06-10 13:31 * @return * @description ： */
    public class ResponseWrapper extends HttpServletResponseWrapper { 
    
        private ByteArrayOutputStream bytes = new ByteArrayOutputStream();
        private HttpServletResponse response;
        private PrintWriter pwrite;
    
        public ResponseWrapper(HttpServletResponse response) { 
            super(response);
            this.response = response;
        }
    
        @Override
        public ServletOutputStream getOutputStream() throws IOException { 
            // 将数据写到 byte 中
            return new MyServletOutputStream(bytes);
        }
    
        /** * 重写父类的 getWriter() 方法，将响应数据缓存在 PrintWriter 中 */
        @Override
        public PrintWriter getWriter() throws IOException { 
            try { 
                pwrite = new PrintWriter(new OutputStreamWriter(bytes, "utf-8"));
            } catch (UnsupportedEncodingException e) { 
                e.printStackTrace();
            }
            return pwrite;
        }
    
        /** * 获取缓存在 PrintWriter 中的响应数据 * * @return */
        public byte[] getBytes() { 
            if (null != pwrite) { 
                pwrite.close();
                return bytes.toByteArray();
            }
    
            if (null != bytes) { 
                try { 
                    bytes.flush();
                } catch (IOException e) { 
                    e.printStackTrace();
                }
            }
            return bytes.toByteArray();
        }
    
        class MyServletOutputStream extends ServletOutputStream { 
            private ByteArrayOutputStream ostream;
    
            public MyServletOutputStream(ByteArrayOutputStream ostream) { 
                this.ostream = ostream;
            }
    
            @Override
            public void write(int b) throws IOException { 
                ostream.write(b); // 将数据写到 stream　中
            }
    
            @Override
            public boolean isReady() { 
                return false;
            }
    
            @Override
            public void setWriteListener(WriteListener listener) { 
    
            }
        }
    
    }

package com.hoau.psb.filter;
    
    import com.alibaba.dubbo.config.annotation.Reference;
    import com.alibaba.fastjson.JSONObject;
    import com.hoau.psb.entity.MonitorData;
    import com.hoau.psb.facade.IhoauMonitorDataFacade;
    import com.hoau.psb.servlet.RequestWrapper;
    import com.hoau.psb.servlet.ResponseWrapper;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.springframework.stereotype.Component;
    
    import javax.servlet.*;
    import javax.servlet.annotation.WebFilter;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import java.io.IOException;
    
    @Component
    @WebFilter(urlPatterns = "/psb/*", filterName = "monitorDataFilter")
    public class MonitorDataFilter implements Filter { 
    
    
        @Reference
        IhoauMonitorDataFacade ihoauMonitorDataServiceImpl;
    
        Log log = LogFactory.getLog(MonitorDataFilter.class);
    
        private MonitorData monitorData;
    
        @Override
        public void init(FilterConfig filterConfig) throws ServletException { 
    
        }
    
        @Override
        public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException { 
    
            HttpServletRequest httpServletRequest = (HttpServletRequest) servletRequest;
            HttpServletResponse httpServletResponse = (HttpServletResponse) servletResponse;
            RequestWrapper requestWrapper = new RequestWrapper(httpServletRequest);
            ResponseWrapper responseWrapper = new ResponseWrapper(httpServletResponse);
    
            filterChain.doFilter(requestWrapper, responseWrapper);
    
            monitorData = new MonitorData();
            String params = null;
            String val = null;
    
            String meth = httpServletRequest.getMethod();
    
            //delete 和put 请求暂时未处理
            if ("POST".equals(meth)) { 
                params = requestWrapper.getBody();
            } else { 
                params = JSONObject.toJSONString(httpServletRequest.getParameterMap());
            }
            log.info(params);
    
            monitorData.setInterAddress(httpServletRequest.getRequestURL().toString());
            monitorData.setAccAccount("");
            monitorData.setAccIP(httpServletRequest.getRemoteAddr());
            monitorData.setAccParams(params);
            monitorData.setInterType("");
    
            byte[] bytes = responseWrapper.getBytes();
            val = new String(bytes, "UTF-8");
            monitorData.setRetVal(JSONObject.toJSONString(val));
    
            log.info(val);
    
            //将数据 再写到 response 中
            servletResponse.getOutputStream().write(bytes);
            servletResponse.getOutputStream().flush();
            servletResponse.getOutputStream().close();
    
            ihoauMonitorDataServiceImpl.addMonitorData(monitorData);
    
        }
    
        @Override
        public void destroy() { 
    
        }
    }

[https_www.jianshu.com_p_69c6fba08c92]: https://www.jianshu.com/p/69c6fba08c92
[https_blog.csdn.net_qq_33206732_article_details_78623042]: https://blog.csdn.net/qq_33206732/article/details/78623042