构建统一的http参数拦截器

目录

• 利用HttpServletRequestWrapper实现请求参数扩展处理
  • 对HttpServletRequestWrapper包装实现
  • 新增过滤器
  • 新增拦截器
  • 配置拦截器
  • 配置过滤器

利用HttpServletRequestWrapper实现请求参数扩展处理

对HttpServletRequestWrapper包装实现

import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;

/**
 *
 * http请求主体包装器
 *
 * @author 唐海斌
 * @date 2021/12/16 14:38
 */
public class BodyHttpServletRequestWrapper extends HttpServletRequestWrapper {
    /**
     * 请求参数字节数组
     */
    private final byte [] bodyBytes;

    public BodyHttpServletRequestWrapper(HttpServletRequest request) throws IOException {
        super(request);
        BufferedInputStream bufferedInputStream = new BufferedInputStream(request.getInputStream());
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        byte [] byteBuffer = new byte[1024];
        int len;
        while ((len = bufferedInputStream.read(byteBuffer, 0, 1024)) != -1) {
            byteArrayOutputStream.write(byteBuffer, 0, len);
        }
        bodyBytes = byteArrayOutputStream.toByteArray();
    }

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

            @Override
            public boolean isFinished() {
                return false;
            }

            @Override
            public boolean isReady() {
                return false;
            }

            @Override
            public void setReadListener(ReadListener readListener) {

            }
        };
    }
}

新增过滤器

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;

/**
 *
 * 参数包装过滤器
 *
 * @author 唐海斌
 * @date 2021/12/16 15:10
 */
public class BodyWrapperFilter implements Filter {

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        if (servletRequest instanceof HttpServletRequest) {
            filterChain.doFilter(new BodyHttpServletRequestWrapper((HttpServletRequest) servletRequest), servletResponse);
        } else {
            filterChain.doFilter(servletRequest, servletResponse);
        }
    }
}

新增拦截器

import com.alibaba.fastjson.JSONObject;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.collections4.MapUtils;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.Map;

/**
 *
 * 参数日志拦截器
 *
 * @author: haibin.tang
 * @date: 2021/3/4
 */
@Slf4j
public class ParamLogInterceptor extends HandlerInterceptorAdapter {

    private final static String LOG_TEMPLATE = "请求资源[%s], 请求参数[%s], 请求主体 %s";

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        byte [] byteBuffer = new byte[1024];
        int len;
        StringBuilder bodyBuilder = new StringBuilder();
        ServletInputStream inputStream = request.getInputStream();
        while ((len = inputStream.read(byteBuffer, 0, 1024)) != -1) {
            bodyBuilder.append(new String(byteBuffer, 0, len));
        }
        log.info(String.format(LOG_TEMPLATE, request.getRequestURI(), parseParamMap(request), bodyBuilder));
        return super.preHandle(request, response, handler);
    }


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

    private String parseParamMap(HttpServletRequest request) {
        Map<String, String[]> parameterMap = request.getParameterMap();
        if (MapUtils.isEmpty(parameterMap)) {
            return null;
        }
        StringBuilder paramBuilder = new StringBuilder();
        parameterMap.forEach((key, value) -> {
            paramBuilder.append(key).append("=").append(JSONObject.toJSONString(value));
        });
        return paramBuilder.toString();
    }
}

配置拦截器

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

/**
 * 拦截器配置
 */
@Configuration
public class InterceptorConfig extends WebMvcConfigurerAdapter {

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(paramLogInterceptor()).addPathPatterns("/trace/**");
    }

    @Bean
    public ParamLogInterceptor paramLogInterceptor() {
        return new ParamLogInterceptor();
    }

    /**
     * 解决跨域问题
     * @param registry
     */
    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**")
                .allowedOrigins("*")
                .allowCredentials(true)
                .allowedMethods("GET", "POST", "DELETE", "PUT")
                .maxAge(3600);
    }
}

配置过滤器

import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.util.Collections;

/**
 * @author 唐海斌
 * @date 2021/12/16 15:16
 */
@Configuration
public class FilterConfiguration {

    @Bean
    FilterRegistrationBean<BodyWrapperFilter> filterFilterRegistrationBean() {
        FilterRegistrationBean<BodyWrapperFilter> bean = new FilterRegistrationBean<>();
        bean.setFilter(new BodyWrapperFilter());
        bean.setOrder(-1);
        bean.setUrlPatterns(Collections.singleton("/trace/*"));
        return bean;
    }
}