Python：Scrapy传入自定义参数运行

# 运行爬虫
$ scrapy crawl spiderName
# 传入自定义参数运行
$ scrapy crawl spiderName -a parameter1=value1 -a parameter2=value2

# -*- coding: utf-8 -*-
import scrapy
from scrapy import cmdline
class BaiduSpider(scrapy.Spider):
    name = 'baidu_spider'
    start_urls = ['https://www.baidu.com/']
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        # 方式一: 在init方法中获取参数
        num = kwargs.get('num')
        print('init num: ', num)
    def parse(self, response):
        # 方式二: 在实例方法中获取参数
        # 如果没有传参数会报错： AttributeError: 'BaiduSpider' object has no attribute 'num'
        print('self.num: ', self.num)
        # 方式三: 在实例方法中获取参数
        num = getattr(self, 'num', False)
        print('getattr: ', num)
if __name__ == '__main__':
    cmdline.execute("scrapy crawl baidu_spider -a num=10".split())