package com.simplemessage.cloudpayservice.infrastructure.config.http;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import java.util.Vector;
/**
 * @CreateAt: 2023/10/24 12:13
 * @ModifyAt: 2023/10/24 12:13
 * @Version 1.0
 */
public class MyRequestWrapper  extends HttpServletRequestWrapper {
    private Map params = new HashMap<>();
    public MyRequestWrapper(HttpServletRequest request, Map newParams) {
        super(request);
        if(request.getParameterMap() != null){
            this.params.putAll(request.getParameterMap());
        }
        if(newParams != null){
            this.params.putAll(newParams);
        }
    }
    /**
     * 獲取參數
     * @return
     */
    @Override
    public Map getParameterMap() {
        return params;
    }
    @Override
    public Enumeration getParameterNames() {
        Vector l = new Vector(params.keySet());
        return l.elements();
    }
    @Override
    public String[] getParameterValues(String name) {
        Object v = params.get(name);
        if (v == null) {
            return null;
        } else if (v instanceof String[]) {
            return (String[]) v;
        } else if (v instanceof String) {
            return new String[]{(String) v};
        } else {
            return new String[]{v.toString()};
        }
    }
    /**
     * 根據參數的key獲取參數
     * @param name
     * @return
     */
    @Override
    public String getParameter(String name) {
        Object v = params.get(name);
        if (v == null) {
            return null;
        } else if (v instanceof String[]) {
            String[] strArr = (String[]) v;
            if (strArr.length > 0) {
                return strArr[0];
            } else {
                return null;
            }
        } else if (v instanceof String) {
            return (String) v;
        } else {
            return v.toString();
        }
    }
}

package com.simplemessage.cloudpayservice.infrastructure.config.http;

import com.fasterxml.jackson.core.io.JsonEOFException;
import lombok.extern.slf4j.Slf4j;
import org.apache.catalina.connector.RequestFacade;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

/**
 * @CreateAt: 2023/10/24 12:16
 * @ModifyAt: 2023/10/24 12:16
 * @Version 1.0
 */
@Slf4j
@Component
@WebFilter(filterName = "replaceGetRequestFilter", urlPatterns = {"/*"})
public class ReplaceGetRequestFilter implements Filter {

    @Override
    public void init(FilterConfig filterConfig) {
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        long start = System.currentTimeMillis();
        //獲取HttpServletRequest對象
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        //判斷當前是否為Get請求
        if ("GET".equalsIgnoreCase(httpServletRequest.getMethod())) {
        	// 獲取參數信息
            String param= request.getParameter("param");
            //判斷參數是否為空，為空則放行
            if (StringUtils.isEmpty(param)) {
                chain.doFilter(request, response);
                return;
            } else {
                Map<String, String[]> newParameterMap = new HashMap<>();
                // 替換參數(自定義規(guī)則)
                String newParama="test";
                newParameterMap.put("param", newParama);
                // 實現參數替換
                MyRequestWrapper myRequestWrapper = new MyRequestWrapper(httpServletRequest, newParameterMap);
                chain.doFilter(myRequestWrapper, response);
            }

        } else {
            try {
                chain.doFilter(request, response);
            } catch (HttpMessageNotReadableException httpMessageNotReadableException) {
                log.error(((RequestFacade) request).getRequestURI() + ", " + httpMessageNotReadableException.getMessage());
            } catch (JsonEOFException jsonEOFException) {
                log.error(((RequestFacade) request).getRequestURI() + ", " + jsonEOFException.getMessage());
            }
        }
        long end = System.currentTimeMillis();
        log.info("{} 接口耗時：{} ms", httpServletRequest.getRequestURI(), (end - start));
    }

    @Override
    public void destroy() {
    }
}

package com.simplemessage.cloudpayservice.infrastructure.config.http;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang.StringUtils;
import org.apache.tomcat.util.http.fileupload.IOUtils;
import org.springframework.core.MethodParameter;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpInputMessage;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.lang.Nullable;
import org.springframework.util.CollectionUtils;
import org.springframework.util.ObjectUtils;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.RequestBodyAdvice;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Type;
import java.util.List;

/**
 * @version 1.0
 * @createAt: 2023/10/24 12:23:23
 * @modifyAt: 2023/10/24 12:23:23
 */
@RestControllerAdvice
@Slf4j
public class DecryptRequestBodyHandler implements RequestBodyAdvice {
    
    /**
     * 該方法用于判斷當前請求，是否要執(zhí)行beforeBodyRead方法
     * methodParameter方法的參數對象
     * type方法的參數類型
     * aClass 將會使用到的Http消息轉換器類類型
     * 注意：此判斷方法，會在beforeBodyRead 和 afterBodyRead方法前都觸發(fā)一次。
     * @return 返回true則會執(zhí)行beforeBodyRead
     */
    @Override
    public boolean supports(MethodParameter methodParameter, Type type, Class<? extends HttpMessageConverter<?>> aClass) {
        return true;
    }

    /**
     * 在Http消息轉換器執(zhí)轉換，之前執(zhí)行
     * inputMessage 客戶端請求的信息
     * parameter 參數信息
     * targetType 參數類型
     * converterType Http消息轉換器類類型
     *
     * @return 返回 一個自定義的HttpInputMessage
     */
    @Override
    public HttpInputMessage beforeBodyRead(HttpInputMessage inputMessage, MethodParameter parameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) throws IOException {
        // 如果body是空內容直接返回原來的請求
        if (inputMessage.getBody().available() <= 0) {
            return inputMessage;
        }
        // 請求中的header信息
        HttpHeaders headers = inputMessage.getHeaders();     
      
        // 將輸入流讀出來，注意 body 里面的流只能讀一次
        ByteArrayOutputStream requestBodyDataByte = new ByteArrayOutputStream();
        try {
        	//復制流信息
            IOUtils.copy(inputMessage.getBody(), requestBodyDataByte);
        } catch (Exception e) {
            log.error("參數流拷貝失敗: ", e.toString());
            return inputMessage;
        }
        ByteArrayOutputStream requestBodyDataByteNew = null;
        try {
            JSONObject body = JSON.parseObject(requestBodyDataByte.toByteArray(), JSONObject.class);
            if (ObjectUtils.isEmpty(body)) {
                return inputMessage;
            }
            //自定義規(guī)則西悉尼
            if (body.containsKey("param")) {
                String custId = body.getString("param"); 
                String newParam="";              
                body.put("custId", newParam);
                requestBodyDataByteNew = new ByteArrayOutputStream();
                //拷貝流信息
                IOUtils.copy(new ByteArrayInputStream(body.toJSONString().getBytes()), requestBodyDataByteNew);
            }
        } catch (Throwable e) {
            log.error("流轉換異常 ", e.toString());
        }
        // 如果上述發(fā)生異常，仍然使用原來的請求內容
        requestBodyDataByte = requestBodyDataByteNew != null ? requestBodyDataByteNew : requestBodyDataByte;
        InputStream rawInputStream = new ByteArrayInputStream(requestBodyDataByte.toByteArray());
        inputMessage.getHeaders().set(HttpHeaders.CONTENT_LENGTH, String.valueOf(rawInputStream.available()));
        return new HttpInputMessage() {
            @Override
            public HttpHeaders getHeaders() {
                return inputMessage.getHeaders();
            }

            @Override
            public InputStream getBody() throws IOException {
                return rawInputStream;
            }
        };
    }

    /**
     * 在Http消息轉換器執(zhí)轉換，之后執(zhí)行
     * body 轉換后的對象
     * inputMessage 客戶端的請求數據
     * parameter handler方法的參數類型
     * targetType handler方法的參數類型
     * converterType 使用的Http消息轉換器類類型
     *
     * @return 返回一個新的對象
     */
    @Override
    public Object afterBodyRead(Object body, HttpInputMessage inputMessage, MethodParameter parameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) {
        return body;
    }

    /**
     * 參數與afterBodyRead相同，不過這個方法body為空的情況
     */
    @Override
    public Object handleEmptyBody(@Nullable Object body, HttpInputMessage inputMessage, MethodParameter parameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) {
        return body;
    }
}