scrapy框架之comand line tool

一 Global Command

　　1 startproject

　　https://docs.scrapy.org/en/latest/topics/commands.html#startproject

　　2 scrapy genspider -t basic baidu www.baidu.com

　　https://docs.scrapy.org/en/latest/topics/commands.html#genspider

　　3 settings

　　https://docs.scrapy.org/en/latest/topics/commands.html#settings

　　4 runspider

　　https://docs.scrapy.org/en/latest/topics/commands.html#runspider

　　5 shell

　　https://docs.scrapy.org/en/latest/topics/commands.html#shell

In [1]: response
Out[1]: <200 https://www.baidu.com>

In [2]: request
Out[2]: <GET https://www.baidu.com>

In [3]: view(response)
Out[3]: True

　　6 fetch

　　https://docs.scrapy.org/en/latest/topics/commands.html#fetch

　　7view 

　　https://docs.scrapy.org/en/latest/topics/commands.html#view

　　8 version

　　https://docs.scrapy.org/en/latest/topics/commands.html#version

二 Project-only Command 

　　1 crawl

　　https://docs.scrapy.org/en/latest/topics/commands.html#crawl

　　2 check

　　https://docs.scrapy.org/en/latest/topics/commands.html#check

　　3 list

　　https://docs.scrapy.org/en/latest/topics/commands.html#list

　　4 edit（没啥用）

　　https://docs.scrapy.org/en/latest/topics/commands.html#edit

　　5 parse

　　https://docs.scrapy.org/en/latest/topics/commands.html#parse

　　6 bench

　　https://docs.scrapy.org/en/latest/topics/commands.html#bench

三 自定义命令

　　官方文档

　　https://docs.scrapy.org/en/latest/topics/commands.html#custom-project-commands

　　定义一个类，继承ScrapyCommand，实现run方法。

四 添加命令行参数

　　在命令行用crawl控制spider爬取的时候，加上-a选项，如

scrapy crawl WangyiSpider -a category=打车

　　然后在 spider 的构造函数里加上带入的参数：

import scrapy
class WangyiSpider(BaseSpider):
    name = "Wangyi"
    def __init__(self, category=None, *args, **kwargs):
        super(WangyiSpider, self).__init__(*args, **kwargs)