python之scrapy模块logging日志

1、知识点

"""
logging :
    scrapy：
        settings中设置LOG_LEVEL="WARNING"
        settings中设置LOG_FILE="./log.log" #设置日志保存的位置，设置后在终端不会显示日志内容
        import logging 实例化一个logger的方式在任何文件中使用logger输出内容
                logger = logging.getLogger(__name__) #实例化
    普通项目中：
        import logging
        logging.basicConfig(level=logging.DEBUG,
                format='%(asctime)s %(filename)s[line:%(lineno)d] %(levelname)s %(message)s',
                datefmt='%a, %d %b %Y %H:%M:%S',
                filename='myapp.log',
                filemode='w') #设置日志输出格式
        实例化一个ogger = logging.getLogger(__name__)
        在任何py文件中调用logger即可
"""

2、scrapy项目中使用logging

# -*- coding: utf-8 -*-
import scrapy
import  logging

logger = logging.getLogger(__name__)
class JulyeduSpider(scrapy.Spider):
    name = 'julyedu'
    allowed_domains = ['julyedu.com']
    start_urls = ['http://julyedu.com/']
    #这个parse方法名不能改
    def parse(self, response):
        """
        爬虫七月在线的导师名单
        :param response:
        :return:
        """
        list_li = response.xpath("//div[@class='swiper-wrapper']//li")
        #print(list_li)
        item = {}
        for li in list_li:
            item["name"] = li.xpath(".//h3/text()").extract_first()
            item["content"] = li.xpath(".//p[@class='teacherBrief']/text()").extract_first()
            #item["content"] = li.xpath(".//p[@class='teacherIntroduction']/text()").extract_first()
            #print(item)
            #将数据传递道pipelines，yield只接受Request,BaseItem，dict,None四种类型
            logger.warning(item) #打印日志
            yield  item

2、普通项目中

　　a)建立一个通用的log_a.py

# coding = utf-8
import  logging
logging.basicConfig(level=logging.DEBUG,
                format='%(asctime)s %(filename)s[line:%(lineno)d] %(levelname)s %(message)s',
                datefmt='%a, %d %b %Y %H:%M:%S',
                filename='myapp.log',
                filemode='w')

logger = logging.getLogger(__name__)

if __name__ == '__main__':
    logger.info("this is a log ")

　　b)log_b.py文件使用通用的log_a.py

# coding = utf-8
from log_a import logger

if __name__ == '__main__':
    logger.warning("b文件")