Python schedule 库定时任务

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Python schedule 库定时任务

schedule的使用

# 用于scrapy定时任务设置
import schedule
import time


def job():
    print("Do Jod", time.time())

    
schedule.every(10).minutes.do(job)
schedule.every().hour.do(job)
schedule.every().day.at("10:30").do(job)
schedule.every(5).to(10).day.do(job)
schedule.every().monday.do(job)
schedule.every().wednesday.at("13:15").do(job)

schedule在scrapy的应用

import subprocess, schedule, time, datetime, logging

from multiprocessing import Process
from scrapy import cmdline


def crawl_work():
    print("I'm working...")
    ## cmd = "scrapy crawl NanPing"
    ## subprocess.Popen(cmd)
    ## run(cmd, shell=True)
    ## pipe = subprocess.Popen(cmd, stdout=subprocess.PIPE).stdout
    ## print(pipe.read())
    print('-'*100)
    args = ["scrapy", "crawl", 'it']
    while True:
        start = time.time()
        p = Process(target=cmdline.execute, args=(args,))
        p.start()
        p.join()
        logging.debug("### use time: %s" % (time.time() - start))


if __name__=='__main__':
    print('*'*10+'开始执行定时爬虫'+'*'*10)
    schedule.every(1).minutes.do(crawl_work)
    print('当前时间为{}'.format(datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')))
    print('*' * 10 + '定时爬虫开始运行' + '*' * 10)
    while True:
        schedule.run_pending()
        time.sleep(10)

Sqlalchemy连接postgresql

import os

from sqlalchemy import create_engine
from sqlalchemy.orm import scoped_session, sessionmaker

# postgresql+psycopg2://username:password@host/dbname
engine = create_engine("postgresql+psycopg2://postgres:88595073@localhost/lecture3")
db = scoped_session(sessionmaker(bind=engine))


def main():
    result = db.execute("SELECT * FROM table_name").fetchall()
    for r in result:
        print(r)

        

if __name__ == "__main__":
	main()

Scrapy通过连接池连接mysql工具

import pymysql
import traceback
from DBUtils.PooledDB import PooledDB
from scrapy.utils.project import get_project_settings


class MySqlUtil(object):
    
    # 获取scrapy中settings的信息
    settings = get_project_settings()
    
    config = {
        "host": settings.get("MYSQL_HOST"),
        "port": settings.get("MYSQL_PORT"),
        "database": settings.get("MYSQL_DATABASE"),
        "user": settings.get("MYSQL_USER"),
        "password": settings.get("MYSQL_PASSWORD"),
        "charset": settings.get("MYSQL_CHARSET")
    }
    
    """
    MYSQL数据库对象，负责产生数据库连接
    """
    
    # 连接池对象
    __pool = None
    
    def __init__(self):
        self._conn = MysqlUtil.get_conn()
        self._cursor = self._conn.cursor()
    
    @staticmethod
    def get_conn():
        """
        @summary: 静态方法，从连接池中取出连接
        @return： MySQLdb.connection
        """
        if MysqlUtil.__pool is None:
            __pool = PooledDB(creator=pymysql, mincached=1, maxcached=20, host=MysqlUtil.config['host'], port=MysqlUtil.config['port'], user=MysqlUtil.config['user'], passwd=MysqlUtil.config['password'], db=MysqlUtil.config['database'], charset=MysqlUtil.config['charset']))
        return __pool.connection()
   	
    def get_all(self, sql, param=None):
        """
        @summary: 执行查询， 并返回所有结果集
        @param sql: 查询sql，如果有查询条件，请指定参数列表，并使用[param]传入
        @param param: 可选参数，条件列表值（元组/列表）
        @return: result list(字典对象)/boolean 查询到的结果集
        """
        try:
            if param is None:
                count = self._cursor.execute(sql)
            else:
                count = self._cursor.execute(sql, param)
            if count > 0:
                result = self._cursor.fetchall()
            else:
                result = False
            return result
        except Exception as e:
            traceback.print_exc(e)
	
    def get_one(self, sql, param=None):
        """
        @summary: 执行查询， 并返回所有结果集
        @param sql: 查询sql，如果有查询条件，请指定参数列表，并使用[param]传入
        @param param: 可选参数，条件列表值（元组/列表）
        @return: result list/boolean 查询到的结果集
        """
        try:
            if param is None:
                count = self._cursor.execute(sql)
            else:
                count = self._cursor.execute(sql, param)
            if count > 0:
                result = self._cursor.fetchone()
            else:
                result = False
            return result
        except Exception as e:
            traceback.print_exc(e)
    
    def get_count(self, sql, param=None):
        """
        @summary: 执行查询， 并返回所有结果集
        @param sql: 查询sql，如果有查询条件，请指定参数列表，并使用[param]传入
        @param param: 可选参数，条件列表值（元组/列表）
        @return: result list/boolean 查询到的结果集
        """
        try:
            if param is None:
                count = self._cursor.execute(sql)
            else:
                count = self._cursor.execute(sql, param)
            return count
        except Exception as e:
            traceback.print_exc(e)
            
    def get_many(self, sql, num, param=None):
        """
        @summary: 执行查询，并取出num条结果
        @param sql:查询sql，如果有查询条件，请只指定条件列表，并将条件值使用参数[param]传递进来
        @param num:取得的结果条数
        @param param: 可选参数，条件列表值（元组/列表）
        @return: result list/boolean 查询到的结果集
        """
        try:
            if param is None:
                count = self._cursor.execute(sql)
            else:
                count = self._cursor.execute(sql, param)
            if count > 0:
                result = self._cursor.fetchmany(num)
            else:
                result = False
            return result
        except Exception as e:
            traceback.print_exc(e)
    
    def insert_one(self, sql, value):
        """
        @summary: 向数据表插入一条记录
        @param sql:要插入的sql格式
        @param value:要插入的记录数据tuple/list
        @return: insertId 受影响的行数
        """
        try:
            row_count = self._cursor.execute(sql, value)
            return row_count
        except Exception as e:
            traceback.print_exc(e)
            self.end("rollback")
     
    def insert_many(self, sql, values):
        """
        @summary: 向数据表插入多条记录
        @param sql:要插入的sql格式
        @param values:要插入的记录数据tuple(tuple)/list[list]
        @return: count 受影响的行数
        """
        try:
            row_count = self._cursor.executemany(sql, values)
            return row_count
        except Exception as e:
            traceback.print_exc(e)
            self.end("rollback")
     
    def __query(self, sql, param=None):
        try:
            if param is None:
                count = self._cursor.execute(sql)
            else:
                count = self._cursor.execute(sql, param)
            return count
        except Exception as e:
            traceback.print_exc(e)

    def update(self, sql, param=None):
        """
        @summary: 更新数据表记录
        @param sql: sql格式及条件，使用(%s,%s)
        @param param: 要更新的  值 tuple/list
        @return: count 受影响的行数
        """
        return self.__query(sql, param)

    def delete(self, sql, param=None):
        """
        @summary: 删除数据表记录
        @param sql: sql格式及条件，使用(%s,%s)
        @param param: 要删除的条件 值 tuple/list
        @return: count 受影响的行数
        """
        return self.__query(sql, param)

    def begin(self):
        """
        @summary: 开启事务
        """
        self._conn.autocommit(0)

    def end(self, option='commit'):
        """
        @summary: 结束事务
        """
        if option == 'commit':
            self._conn.commit()
        else:
            self._conn.rollback()

    def dispose(self, is_end=1):
        """
        @summary: 释放连接池资源
        """
        if is_end == 1:
            self.end('commit')
        else:
            self.end('rollback')
        self._cursor.close()
        self._conn.close()

# 调用 pipeline
from torrentSpider.utils.db_util import MysqlUtil
import traceback
import logging


class MySqlPipeline(object):
    pool = None

    def __init__(self):
        pass

    # 开启爬虫时链接数据库
    def open_spider(self, spider):
        self.pool = MysqlUtil()

    # 处理
    def process_item(self, item, spider):
        try:
            # 执行sql语句
            # sql = "select * from torrent_ye"
            # count = self.pool.get_all(sql, None)
            # print('查询数量为：' + str(count))

            # 先去数据库查询，查到了就不入库了
            sql_select = """select count(1) from torrent_ye where torrent_url = %(torrent_url)s"""
            params_select = {'torrent_url': item['torrent_url']}
            flag = self.pool.get_count(sql_select, params_select)
            if flag > 0:
                logging.info('记录已经存在:[%s][%s]', item['torrent_title'], item['torrent_url'])
                return

            sql_insert = """insert into torrent_ye(torrent_title, torrent_name, torrent_director,
            torrent_actor, torrent_language, torrent_type, torrent_region, torrent_update_time,
            torrent_status, torrent_show_time, torrent_introduction, torrent_url) values
             (%(torrent_title)s,%(torrent_name)s,%(torrent_director)s,%(torrent_actor)s,%(torrent_language)s,
             %(torrent_type)s,%(torrent_region)s,%(torrent_update_time)s,%(torrent_status)s,%(torrent_show_time)s,%(torrent_introduction)s,%(torrent_url)s)"""

            params = {'torrent_title': item['torrent_title'], 'torrent_name': item['torrent_name'],
                      'torrent_director': item['torrent_director'], 'torrent_actor': item['torrent_actor'],
                      'torrent_language': item['torrent_language'], 'torrent_type': item['torrent_type'],
                      'torrent_region': item['torrent_region'], 'torrent_update_time': item['torrent_update_time'],
                      'torrent_status': item['torrent_status'], 'torrent_show_time': item['torrent_show_time'],
                      'torrent_introduction': item['torrent_introduction'], 'torrent_url': item['torrent_url']}

            self.pool.insert_one(sql_insert, params)
            self.pool.end("commit")
        except Exception as e:
            logging.error('发生异常:[%s]', e)
            traceback.print_exc(e)
            self.pool.end("rollback")

    # 结束
    def close_spider(self, spider):
        pass

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