Druid 简单介绍和配置及使用

加耀 2018-11-18

2565

1. Druid--是什么？

目前常见的数据库连接池主要有c3p0，dbcp，tomcat-jdbc-pool，druid，HiKariCP等，druid是阿里创建的一个开源项目，简称阿里Druid，是目前最好用的数据库连接池之一；

2. Druid--做什么？

Druid能够为我们提供强大的监控和扩展功能，方便我们数据源信息(基本上能够获取所有熟悉)，能够实施为我们提供SQL监控(常用定位慢查询和并发数等)，能够为我们提供数据库中数据表访问统计，能够为我们提供URL监控，能够提供Session监控，能够提供Spring监控等等强大的功能；

3. Druid--怎么用？

下面以SpringBoot项目为例：

首先在pom.xml文件中引入如下依赖

<!-- Druid数据库连接池 -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.1.12</version>
</dependency>复制

Druid的配置文件主要有如下，在我们application.yml文件中的配置：

spring:
  datasource:
      url: jdbc:mysql://ip:3306/数据库名?autoReconnect=true&useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useAffectedRows=true
      username: root
      password: root
      # 配置监控统计拦截的filters，去掉后监控界面sql无法统计
     filters: log4j,wall,mergeStat
      initialSize: 10
      maxActive: 200
      minIdle: 10
      maxWait: 60000
      # 通过connectProperties属性来打开mergeSql功能；慢SQL记录
     connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
      # 合并多个DruidDataSource的监控数据
     useGlobalDataSourceStat: true
      druidUserName: admin
      druidPassWord: 123456复制

实现数据库监控，首先需要一个创建一个监听器以及过滤器等，这里我一共写了四个类，分别是：

DruidConfig.java
ConfigListener.java
XssFilter.java
XssHttpServletrRequestWrapper.java

复制

代码如下：

package cn.jiayao.druidtest.config.web;

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import com.alibaba.druid.support.spring.stat.BeanTypeAutoProxyCreator;
import com.alibaba.druid.support.spring.stat.DruidStatInterceptor;
import org.springframework.aop.Advisor;
import org.springframework.aop.support.DefaultPointcutAdvisor;
import org.springframework.aop.support.JdkRegexpMethodPointcut;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletListenerRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.context.request.RequestContextListener;

import java.util.Arrays;

/**
 * web 配置类
 */
@Configuration
public class DruidConfig {

    /**
     * druidServlet注册
     */
    @Bean
    public ServletRegistrationBean druidServletRegistration() {
        ServletRegistrationBean registration = new ServletRegistrationBean(new StatViewServlet());
        registration.addUrlMappings("/druid/*");
        //登录查看信息的账号密码.
        registration.addInitParameter("loginUsername", "admin");
        registration.addInitParameter("loginPassword", "123456");
        // 白名单： 如果没有配置的话及所有的都可以访问
//        registration.addInitParameter("allow", "127.0.0.1");
        // IP黑名单 (存在共同时，deny优先于allow) : 如果满足deny的话提示:Sorry, you are not permitted to view this page.
        registration.addInitParameter("deny", "192.168.1.73");
        return registration;
    }

    /**
     * druid监控 配置URI拦截策略
     *
     * @return
     */
    @Bean
    public FilterRegistrationBean druidStatFilter() {
        FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter());
        //添加过滤规则.
        filterRegistrationBean.addUrlPatterns("/*");
        //添加不需要忽略的格式信息.
        filterRegistrationBean.addInitParameter(
                "exclusions", "/static/*,*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid,/druid/*");
        //用于session监控页面的用户名显示 需要登录后主动将username注入到session里
        filterRegistrationBean.addInitParameter("principalSessionName", "username");
        return filterRegistrationBean;
    }

    /**
     * druid数据库连接池监控
     */
    @Bean
    public DruidStatInterceptor druidStatInterceptor() {
        return new DruidStatInterceptor();
    }


    @Bean
    public JdkRegexpMethodPointcut druidStatPointcut() {
        JdkRegexpMethodPointcut druidStatPointcut = new JdkRegexpMethodPointcut();
        String patterns = "com.esgcc.platform.activity.modular.*.service.*";
        //可以set多个
        druidStatPointcut.setPatterns(patterns);
        return druidStatPointcut;
    }

    /**
     * druid数据库连接池监控
     */
    @Bean
    public BeanTypeAutoProxyCreator beanTypeAutoProxyCreator() {
        BeanTypeAutoProxyCreator beanTypeAutoProxyCreator = new BeanTypeAutoProxyCreator();
        beanTypeAutoProxyCreator.setTargetBeanType(DruidDataSource.class);
        beanTypeAutoProxyCreator.setInterceptorNames("druidStatInterceptor");
        return beanTypeAutoProxyCreator;
    }

    /**
     * druid 为druidStatPointcut添加拦截
     *
     * @return
     */
    @Bean
    public Advisor druidStatAdvisor() {
        return new DefaultPointcutAdvisor(druidStatPointcut(), druidStatInterceptor());
    }

    /**
     * xssFilter注册
     */
    @Bean
    public FilterRegistrationBean xssFilterRegistration() {
        XssFilter xssFilter = new XssFilter();
        xssFilter.setUrlExclusion(Arrays.asList("/notice/update", "/notice/add"));
        FilterRegistrationBean registration = new FilterRegistrationBean(xssFilter);
        registration.addUrlPatterns("/*");
        return registration;
    }

    /**
     * RequestContextListener注册
     */
    @Bean
    public ServletListenerRegistrationBean<RequestContextListener> requestContextListenerRegistration() {
        return new ServletListenerRegistrationBean<>(new RequestContextListener());
    }

    /**
     * ConfigListener注册
     */
    @Bean
    public ServletListenerRegistrationBean<ConfigListener> configListenerRegistration() {
        return new ServletListenerRegistrationBean<>(new ConfigListener());
    }

}
复制

这里需要引用其他的几个类：

package cn.jiayao.druidtest.config.web;

import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import java.util.HashMap;
import java.util.Map;

public class ConfigListener implements ServletContextListener {

    private static Map<String, String> conf = new HashMap<>();

    public static Map<String, String> getConf() {
        return conf;
    }

    @Override
    public void contextDestroyed(ServletContextEvent arg0) {
        conf.clear();
    }

    @Override
    public void contextInitialized(ServletContextEvent evt) {
        ServletContext sc = evt.getServletContext();
        // 项目路径
        conf.put("realPath", sc.getRealPath("/").replaceFirst("/", ""));
        conf.put("contextPath", sc.getContextPath());
    }

}
复制

package cn.jiayao.druidtest.config.web;



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


public class XssFilter implements Filter {

    FilterConfig filterConfig = null;

    private List<String> urlExclusion = null;

    public void init(FilterConfig filterConfig) throws ServletException {
        this.filterConfig = filterConfig;
    }

    public void destroy() {
        this.filterConfig = null;
    }

    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        String servletPath = httpServletRequest.getServletPath();

        if (urlExclusion != null && urlExclusion.contains(servletPath)) {
            chain.doFilter(request, response);
        } else {
            chain.doFilter(new XssHttpServletRequestWrapper((HttpServletRequest) request), response);
        }
    }

    public List<String> getUrlExclusion() {
        return urlExclusion;
    }

    public void setUrlExclusion(List<String> urlExclusion) {
        this.urlExclusion = urlExclusion;
    }
}复制

package cn.jiayao.druidtest.config.web;


import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;


public class XssHttpServletRequestWrapper extends HttpServletRequestWrapper {

    public XssHttpServletRequestWrapper(HttpServletRequest servletRequest) {

        super(servletRequest);

    }

    public String[] getParameterValues(String parameter) {

        String[] values = super.getParameterValues(parameter);

        if (values == null) {

            return null;

        }

        int count = values.length;

        String[] encodedValues = new String[count];

        for (int i = 0; i < count; i++) {

            encodedValues[i] = cleanXSS(values[i]);

        }

        return encodedValues;

    }

    public String getParameter(String parameter) {

        String value = super.getParameter(parameter);

        if (value == null) {

            return null;

        }

        return cleanXSS(value);

    }

    public String getHeader(String name) {

        String value = super.getHeader(name);

        if (value == null)

            return null;

        return cleanXSS(value);

    }

    private String cleanXSS(String value) {

        //You'll need to remove the spaces from the html entities below

        value = value.replaceAll("<", "& lt;").replaceAll(">", "& gt;");

        value = value.replaceAll("\\(", "& #40;").replaceAll("\\)", "& #41;");

        value = value.replaceAll("'", "& #39;");

        value = value.replaceAll("eval\\((.*)\\)", "");

        value = value.replaceAll("[\\\"\\\'][\\s]*javascript:(.*)[\\\"\\\']", "\"\"");

        value = value.replaceAll("script", "");

        return value;

    }


}复制