springboot配置Druid数据源监控页面

使用场景：
为什么用druid监控页面，因为定时任务总是删除activiti中的act开头的表，于是druid来监控sql.

1、首先maven引入durid中依赖包

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid-spring-boot-starter</artifactId>
    <version>${druid.version}</version>
</dependency>

2、本人用的是nacos，有些微服务不起作用，后来直接用配置类来解决的，配置如下：

# spring配置
spring: 
  redis:
    host: 127.0.0.1
    port: 6379
    password: 123456
    database: 2    
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true&serverTimezone=GMT%2B8
    username: root
    password: 123456
    druid:
      stat-view-servlet:
        enabled: true
        url-pattern: /druid/*
        loginUsername: admin
        loginPassword: 123456
    #   数据源其他配置
    initialSize: 5
    minIdle: 5
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true
    #配置监控统计拦截的filters，去掉后监控界面sql无法统计，'wall'用于防火墙  
    filters: stat,wall
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true  
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500
# mybatis配置
mybatis:
    # 搜索指定包别名
    typeAliasesPackage: com.ruoyi.job.domain
    # 配置mapper的扫描，找到所有的mapper.xml映射文件
    mapperLocations: classpath:mapper/**/*.xml

# swagger配置
swagger:
  title: 定时任务接口文档
  license: Powered By ruoyi
  licenseUrl: https://ruoyi.vip

http:
  maxTotal: 100
  defaultMaxPerRoute: 20
  connectTimeout: 100000
  connectionRequestTimeout: 50000
  socketTimeout: 100000
  staleConnectionCheckEnabled: true

3、如果以上配置无效，添加配置类

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.spring.boot.autoconfigure.properties.DruidStatProperties;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import com.alibaba.druid.util.Utils;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

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

/**
 * druid 配置多数据源
 *
 * @author defu
 */
@Configuration
public class DruidConfig {

    @ConfigurationProperties(prefix = "spring.datasource")
    @Bean
    public DruidDataSource druidDataSource() {
        return new DruidDataSource();
    }


    /**
     * 配置监控服务器
     *
     * @return 返回监控注册的servlet对象
     * @author SimpleWu
     */
    @Bean
    public ServletRegistrationBean statViewServlet() {
        ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
        // 添加IP白名单
        servletRegistrationBean.addInitParameter("allow", "127.0.0.1");
        // 添加IP黑名单，当白名单和黑名单重复时，黑名单优先级更高
        servletRegistrationBean.addInitParameter("deny", "127.0.0.1");
        // 添加控制台管理用户
        servletRegistrationBean.addInitParameter("loginUsername", "admin");
        servletRegistrationBean.addInitParameter("loginPassword", "123456");
        // 是否能够重置数据
        servletRegistrationBean.addInitParameter("resetEnable", "false");
        return servletRegistrationBean;
    }

    /**
     * 配置服务过滤器
     *
     * @return 返回过滤器配置对象
     */
    @Bean
    public FilterRegistrationBean statFilter() {
        FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter());
        // 添加过滤规则
        filterRegistrationBean.addUrlPatterns("/*");
        // 忽略过滤格式
        filterRegistrationBean.addInitParameter("exclusions", "*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*,");
        return filterRegistrationBean;
    }

    /**
     * 去除监控页面底部的广告
     */
    @SuppressWarnings({"rawtypes", "unchecked"})
    @Bean
    @ConditionalOnProperty(name = "spring.datasource.druid.statViewServlet.enabled", havingValue = "true")
    public FilterRegistrationBean removeDruidFilterRegistrationBean(DruidStatProperties properties) {
        // 获取web监控页面的参数
        DruidStatProperties.StatViewServlet config = properties.getStatViewServlet();
        // 提取common.js的配置路径
        String pattern = config.getUrlPattern() != null ? config.getUrlPattern() : "/druid/*";
        String commonJsPattern = pattern.replaceAll("\\*", "js/common.js");
        final String filePath = "support/http/resources/js/common.js";
        // 创建filter进行过滤
        Filter filter = new Filter() {
            @Override
            public void init(javax.servlet.FilterConfig filterConfig) throws ServletException {
            }

            @Override
            public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
                    throws IOException, ServletException {
                chain.doFilter(request, response);
                // 重置缓冲区，响应头不会被重置
                response.resetBuffer();
                // 获取common.js
                String text = Utils.readFromResource(filePath);
                // 正则替换banner, 除去底部的广告信息
                text = text.replaceAll("<a.*?banner\"></a><br/>", "");
                text = text.replaceAll("powered.*?shrek.wang</a>", "");
                response.getWriter().write(text);
            }

            @Override
            public void destroy() {
            }
        };
        FilterRegistrationBean registrationBean = new FilterRegistrationBean();
        registrationBean.setFilter(filter);
        registrationBean.addUrlPatterns(commonJsPattern);
        return registrationBean;
    }

}