zoukankan      html  css  js  c++  java
  • spring boot拦截器中获取request post请求中的参数

    最近有一个需要从拦截器中获取post请求的参数的需求,这里记录一下处理过程中出现的问题。
    首先想到的就是request.getParameter(String )方法,但是这个方法只能在get请求中取到参数,post是不行的,后来想到了使用流的方式,调用request.getInputStream()获取流,然后从流中读取参数,如下代码所示:

    String body = "";
    StringBuilder stringBuilder = new StringBuilder();
    BufferedReader bufferedReader = null;
    InputStream inputStream = null;
    try {
    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) {
    e.printStackTrace();
    } finally {
    if (inputStream != null) {
    try {
    inputStream.close();
    }
    catch (IOException e) {
    e.printStackTrace();
    }
    }
    if (bufferedReader != null) {
    try {
    bufferedReader.close();
    }
    catch (IOException e) {
    e.printStackTrace();
    }
    }
    }
    body = stringBuilder.toString();
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    代码中的body就是request中的参数,我这里传的是JSON数据:{“page”: 1, “pageSize”: 10},那么body就是:body = “{“page”: 1, “pageSize”: 10}”,一个JSON字符串。这样是可以成功获取到post请求的body,但是,经过拦截器后,参数经过@RequestBody注解赋值给controller中的方法的时候,却抛出了一个这样的异常:

    org.springframework.http.converter.HttpMessageNotReadableException: Required request body is missing
    request的输入流只能读取一次,那么这是为什么呢?下面是答案:

    那是因为流对应的是数据,数据放在内存中,有的是部分放在内存中。read 一次标记一次当前位置(mark position),第二次read就从标记位置继续读(从内存中copy)数据。 所以这就是为什么读了一次第二次是空了。 怎么让它不为空呢?只要inputstream 中的pos 变成0就可以重写读取当前内存中的数据。javaAPI中有一个方法public void reset() 这个方法就是可以重置pos为起始位置,但是不是所有的IO读取流都可以调用该方法!ServletInputStream是不能调用reset方法,这就导致了只能调用一次getInputStream()。
    那么有什么办法可以用户解决呢?上面这篇博客中提到了解决方案,就是重写HttpServletRequestWrapper把request保存下来,然后通过过滤器把保存下来的request再填充进去,这样就可以多次读取request了。步骤如下所示:

    ①写一个类,继承HttpServletRequestWrapper

    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) {
    super(request);
    StringBuilder stringBuilder = new StringBuilder();
    BufferedReader bufferedReader = null;
    InputStream inputStream = null;
    try {
    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) {

    } finally {
    if (inputStream != null) {
    try {
    inputStream.close();
    }
    catch (IOException e) {
    e.printStackTrace();
    }
    }
    if (bufferedReader != null) {
    try {
    bufferedReader.close();
    }
    catch (IOException e) {
    e.printStackTrace();
    }
    }
    }
    body = stringBuilder.toString();
    }

    @Override
    public ServletInputStream getInputStream() throws IOException {
    final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(body.getBytes());
    ServletInputStream servletInputStream = new ServletInputStream() {
    @Override
    public boolean isFinished() {
    return false;
    }
    @Override
    public boolean isReady() {
    return false;
    }
    @Override
    public void setReadListener(ReadListener readListener) {
    }
    @Override
    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;
    }

    }
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    62
    63
    64
    65
    66
    67
    68
    69
    70
    71
    72
    73
    74
    75
    76
    77
    78
    79
    80
    81
    82
    83
    ②拦截器层面

    import com.alibaba.fastjson.JSON;
    import com.miniprogram.api.douyin.user.req.DyuserReq;
    import com.miniprogram.common.auth.VisitLimitCount;
    import com.miniprogram.common.cache.RedisCache;
    import com.miniprogram.common.config.InterceptorConfigMap;
    import com.miniprogram.common.config.InterceptorUrlConfig;
    import com.miniprogram.common.douyin.SearchEngineMapConstants;
    import com.miniprogram.common.response.Response;
    import com.miniprogram.common.session.*;
    import com.miniprogram.common.utils.DateUtil;
    import com.miniprogram.dao.common.UserLoginEntity.Users;
    import com.miniprogram.service.douyin.users.UsersService;
    import com.miniprogram.web.douyin.config.RequestWrapper;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.BeanUtils;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Component;
    import org.springframework.web.servlet.ModelAndView;
    import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import java.io.BufferedReader;
    import java.io.InputStreamReader;
    import java.util.ArrayList;
    import java.util.HashMap;
    import java.util.List;
    import java.util.Map;

    @Component("authSecurityInterceptor")
    public class AuthSecurityInterceptor extends HandlerInterceptorAdapter {
    private Logger logger = LoggerFactory.getLogger(AuthSecurityInterceptor.class);

    @Autowired
    private RedisCache redisCache;
    @Autowired
    private VisitLimitCount visitLimitCount;

    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
    try {
    RequestWrapper requestWrapper = new RequestWrapper(httpServletRequest);
    String body = requestWrapper.getBody();
    System.out.println(body);
    return true;
    }catch (Exception e){
    logger.error("权限判断出错",e);
    }
    return false;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
    }
    }
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    ③过滤器Filter,用来把request传递下去

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

    @WebFilter(urlPatterns = "/*",filterName = "channelFilter")
    public class ChannelFilter implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

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

    @Override
    public void destroy(http://www.my516.com) {

    }
    }
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    ④在启动类中注册拦截器

    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.boot.web.servlet.MultipartConfigFactory;
    import org.springframework.boot.web.servlet.ServletComponentScan;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.ComponentScan;
    import org.springframework.context.annotation.Configuration;

    @SpringBootApplication
    // @ServletComponentScan //注册过滤器注解
    @Configuration
    public class WebApplication {

    public static void main(String[] args) {
    SpringApplication.run(WebApplication.class, args);
    }
    }
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    经测试,问题解决
    ---------------------

  • 相关阅读:
    tomcat调优
    使用Docker部署Spring Boot项目
    java配置ueditor中解决“未找到上传文件”错误提示
    java.lang.NoClassDefFoundError: org/aspectj/weaver/reflect/ReflectionWorld$ReflectionWorldException
    spring01
    android中的wrap_content,match_parent, fill_parent
    RPC和http
    Failed to read artifact descriptor for xxx
    Error processing condition on org.springframework.boot.autoconfigure.thymeleaf.ThymeleafAutoConfiguration$ThymeleafWebMvcConfiguration.resourceUrlEncodingFilter
    springboot的自动配置
  • 原文地址:https://www.cnblogs.com/ly570/p/11183002.html
Copyright © 2011-2022 走看看