python多线程使用场景：多线程采集, 以及性能测试等 。

数据库驱动类-简单封装下

mysqlDriver.py

#!/usr/bin/python3#-*- coding: utf-8 -*-# author:zhouchao# mysql 驱动模型类import pymysql;import traceback; class mysqlDriver:    host="localhost";    user="root";    password="";    database="fitcmoe_boke";    charset="GBK";    db = "false";    # 连接数据库    def connect(self, host="", user="",password="",database="",charset = ""):        if host and user :            self.host = host;            self.user = user;            self.password = password;            self.database = database;            self.charset = charset;        self.db=pymysql.connect(host=self.host,user=self.user,password=self.password,database=self.database,charset=self.charset);    # 查询多条    def select(self,sql,params = []):        if params :            sql = self.bindParams(sql, params);        # print(sql);return;        cursor = self.db.cursor();        cursor.execute(sql);        data = cursor.fetchall();        self.db.close();        return data;    # 查询单条    def find(self,sql,params = []):        if params :            sql = self.bindParams(sql, params);        cursor = self.db.cursor();        cursor.execute(sql);        data = cursor.fetchone();        self.db.close();        return data;    # 新增    def add(self,sql,params=[]):        if params :            sql = self.bindParams(sql, params);        try:            cursor = self.db.cursor();            cursor.execute(sql);            newId = self.db.insert_id();            self.db.commit();            self.db.close();            return newId;           except "involid level":           # 发生错误时回滚           print("发生异常","involid level");           self.db.rollback();           self.db.close();    # 更新    def save(self,sql,params=[]):        if params :            sql = self.bindParams(sql, params);        try:            cursor = self.db.cursor();            resultNum=cursor.execute(sql);            self.db.commit();            self.db.close();            return resultNum;           except "involid level":           # 发生错误时回滚           print("发生异常","involid level");           self.db.rollback();           self.db.close();    def delete(self,sql,params=[]):        if params :            sql = self.bindParams(sql, params);            # self.file_put_contents('rt.txt',sql,'append');            # print(sql);return;        try:            cursor = self.db.cursor();            resultNum=cursor.execute(sql);            self.db.commit();            self.db.close();            return resultNum;           except "involid level":           # 发生错误时回滚           print("发生异常","involid level");           self.db.rollback();           self.db.close();                # 参数绑定  空格好奇怪啊    def bindParams(self,sql, params):        finalSql = "";        length = len(sql);        replaceNum = 0;        for x in sql:             if x == "?":               x = params[replaceNum];               typeX = type(x);               if typeX.__name__ == "list":                    temp = '(';                    for t in x:                        temp +=  "'" +str(t)+"',";                    x=temp.rstrip(",");                    x+=")";               else :                    if str(x).isdigit() :                        x = int(x);                    else:                        x = "'" +str(x) +"'";                                                          replaceNum = replaceNum + 1;            finalSql += str(x);            # finalSql += x;        return finalSql;    # 将sql 写入本地文件    # r+ = pappend 向前追加    # w+ = 覆盖添加      # a+ = append  向后追加    def file_put_contents(self,fileName,content,modeName =''):          if(modeName == 'pappend'):          mode = "r+";        elif(modeName == 'append'):         mode = "a+";        else:         mode = "w+";        fileObject = open(fileName,mode);        fileObject.write(content);        fileObject.close();# 使用说明 异常处理类问题？？# ? 代表参数# ? 可以是列表或数字  如  [1,3,5,7]  和 3 # # 参数位置是按照顺序的 # 简单使用# mysqlD = mysqlDriver();# mysqlD.connect();# data = mysqlD.select("select from t_article where id in ? limit ? ",[[33,34,35,38],3]);# data = mysqlD.delete("delete from t_article where aid in ?",[[43,44,270,280]]);

文件下载函数

file_get_contents.py

#!/usr/bin/python3#-*- coding: utf-8 -*-# author:zhouchao# 文件处理函数def file_get_contents(path,mode="r+"):    fileObject = open(path,mode);    content = fileObject.read();    fileObject.close();    return content;# r+ = pappend 向前追加# w+ = 覆盖添加  # a+ = append  向后追加# wb+ 直接使用二进制添加def file_put_contents(fileName,content,modeName =''):      if(modeName == 'pappend'):      mode = "r+";    elif(modeName == 'append'):     mode = "a+";    elif(modeName == 'wb+'):     mode = "wb+";    else:     mode = "w+";    fileObject = open(fileName,mode);    fileObject.write(content);    fileObject.close();# file_put_contents('rt.txt','da ge');

批量远程图片下载

multiPool.py

#!/usr/bin/python3#-*- coding: utf-8 -*-# author:zhouchao# 功能：多线程 批量下载远程图片import randomimport timeimport osimport mathfrom multiprocessing.dummy import Pool as ThreadPoolimport urllib.requestimport requestsimport syssys.path.append(r"../db")sys.path.append(r"../function")from file_get_contents import *from mysqlDriver import *sql = "select img from images limit ?";mysqlD = mysqlDriver();mysqlD.connect();data = mysqlD.select(sql, [100])saveDir = "D:/images/";def  downImg(url):    url = url[0];    ir = requests.get(url)    if ir.status_code == 200:        # wb+  保存二进制        fileName = str(time.time()) +'.jpg';        file_put_contents(saveDir+fileName,ir.content,"wb+");startTime = time.time();# 不开启多线程# length = len(data);# for x in range(length):#     downImg(data[x][0])# 开启多线程pool = ThreadPool(8) # Sets the pool size to 4results = pool.map(downImg,data);pool.close();pool.join();endTime = time.time();consumeTime = endTime - startTimeprint("程序运行时间："+str(consumeTime)+" 秒")

注意：

sys.path.append(r"../db")sys.path.append(r"../function") 请引用自己保存文件路径 没有开启和开启多线程所耗时间：