Python scrapy框架的简单使用

C:\Users\AOBO>scrapy -h
Scrapy 1.2.1 - no active project
使用格式:
  scrapy <command> [options] [args]
可用的命令:
  bench         测试本地硬件性能（工作原理：）：scrapy bench
  commands
  fetch         取URL使用Scrapy下载
  genspider     产生新的蜘蛛使用预先定义的模板
  runspider     运用单独一个爬虫文件：scrapy runspider abc.py
  settings      获取设置值
  shell         进入交互终端，用于爬虫的调试（如果你不调试，那么就不常用）：scrapy shell http://www.baidu.com --nolog（--nolog 不显示日志信息）
  startproject  创建一个爬虫项目，如：scrapy startproject demo（demo 创建的爬虫项目的名字）
  version       查看版本：（scrapy version）
  view          下载一个网页的源代码，并在默认的文本编辑器中打开这个源代码：scrapy view http://www.aobossir.com/
  [ more ]      从项目目录运行时可获得更多命令
使用 "scrapy <command> -h" 要查看有关命令的更多信息

D:\BaiduYunDownload\first>scrapy -h
Scrapy 1.2.1 - project: first
Usage:
  scrapy <command> [options] [args]
Available commands:
  bench         Run quick benchmark test
  check         Check spider contracts
  commands
  crawl         运行一个爬虫文件。：scrapy crawl f1 或者 scrapy crawl f1 --nolog
  edit          使用编辑器打开爬虫文件 （Windows上似乎有问题，Linux上没有问题）：scrapy edit f1
  fetch         Fetch a URL using the Scrapy downloader
  genspider     Generate new spider using pre-defined templates
  list          列出当前爬虫项目下所有的爬虫文件：scrapy list
  parse         Parse URL (using its spider) and print the results
  runspider     Run a self-contained spider (without creating a project)
  settings      获取设置值
  shell         进入交互终端，用于爬虫的调试（如果你不调试，那么就不常用）
  startproject  创建一个爬虫项目，如：scrapy startproject demo（demo 创建的爬虫项目的名字）
  version       查看版本：（scrapy version）
  view          下载一个网页的源代码，并在默认的文本编辑器中打开这个源代码
Use "scrapy <command> -h" to see more info about a command

scrapy -h

scapy --help

(venv)ql@ql:~$ scrapy version
Scrapy 1.1.2
(venv)ql@ql:~$
(venv)ql@ql:~$ scrapy version -v
Scrapy    : 1.1.2
lxml      : 3.6.4.0
libxml2   : 2.9.4
Twisted   : 16.4.0
Python    : 2.7.12 (default, Jul  1 2016, 15:12:24) - [GCC 5.4.0 20160609]
pyOpenSSL : 16.1.0 (OpenSSL 1.0.2g-fips  1 Mar 2016)
Platform  : Linux-4.4.0-36-generic-x86_64-with-Ubuntu-16.04-xenial
(venv)ql@ql:~$

scrapy startproject spider_name

scrapy genspider name domain
#如:
#scrapy genspider sohu sohu.org

scrapy list

scrapy view http://www.baidu.com

# 进入该url的交互环境
scrapy shell http://www.dmoz.org/Computers/Programming/Languages/Python/Books/

response.xpath()    #括号里直接加xpath路径

scrapy runspider 爬虫名称

scrapy startproject  demo

demo
├── demo
│   ├── __init__.py
│   ├── __pycache__
│   ├── items.py        # Items的定义，定义抓取的数据结构
│   ├── middlewares.py  # 定义Spider和DownLoader的Middlewares中间件实现。
│   ├── pipelines.py    # 它定义Item Pipeline的实现，即定义数据管道
│   ├── settings.py     # 它定义项目的全局配置
│   └── spiders         # 其中包含一个个Spider的实现，每个Spider都有一个文件
│       ├── __init__.py
│       └── __pycache__
└── scrapy.cfg    #Scrapy部署时的配置文件，定义了配置文件路径、部署相关信息等内容

scrapy genspider fang fang.5i5j.com
$ tree
├── demo
│   ├── __init__.py
│   ├── __pycache__
│   │   ├── __init__.cpython-36.pyc
│   │   └── settings.cpython-36.pyc
│   ├── items.py
│   ├── middlewares.py
│   ├── pipelines.py
│   ├── settings.py
│   └── spiders
│       ├── __init__.py
│       ├── __pycache__
│       │   └── __init__.cpython-36.pyc
│       └── fang.py  #在spiders目录下有了一个爬虫类文件fang.py
└── scrapy.cfg
# fang.py的文件代码如下：
# -*- coding: utf-8 -*-
import scrapy
class FangSpider(scrapy.Spider):
    name = 'fang'
    allowed_domains = ['fang.5i5j.com']
    start_urls = ['http://fang.5i5j.com/']
    def parse(self, response):
        pass

import scrapy
class FangItem(scrapy.Item):
    # define the fields for your item here like:
    title = scrapy.Field()
    address = scrapy.Field()
    time = scrapy.Field()
    clicks = scrapy.Field()
    price = scrapy.Field()
    #pass

# -*- coding: utf-8 -*-
import scrapy
from demo.items import FangItem
class FangSpider(scrapy.Spider):
    name = 'fang'
    allowed_domains = ['fang.5i5j.com']
    #start_urls = ['http://fang.5i5j.com/']
    start_urls = ['https://fang.5i5j.com/bj/loupan/']
    def parse(self, response):
        hlist = response.css("div.houseList_list")
        for vo in hlist:
            item = FangItem()
            item['title'] =  vo.css("h3.fontS20 a::text").extract_first()
            item['address'] =  vo.css("span.addressName::text").extract_first()
            item['time'] =  vo.re("<span>(.*?)开盘</span>")[0]
            item['clicks'] =  vo.re("<span><i>([0-9]+)</i>浏览</span>")[0]
            item['price'] =  vo.css("i.fontS24::text").extract_first()
            #print(item)
            yield item

class DemoPipeline(object):
    def process_item(self, item, spider):
        print(item)
        return item

scrapy crawl fang

scrapy crawl fang -o fangs.json
scrapy crawl fang -o fangs.csv
scrapy crawl fang -o fangs.xml
scrapy crawl fang -o fangs.pickle
scrapy crawl fang -o fangs.marshal

scrapy genspider youdao fanyi.youdao.com

# -*- coding: utf-8 -*-
import scrapy,json
class YoudaoSpider(scrapy.Spider):
    name = 'youdao'
    allowed_domains = ['fanyi.youdao.com']
    #start_urls = ['http://fanyi.youdao.com']
    def start_requests(self):
        url = 'http://fanyi.youdao.com/translate?smartresult=dict&smartresult=rule'
        keyword = input("请输入要翻译的单词：")
        data = {'i':keyword,'doctype': 'json',}
        # FormRequest 是Scrapy发送POST请求的方法
        yield scrapy.FormRequest(
            url = url,
            formdata = data,
            callback = self.parse
        )
    def parse(self, response):
        res = json.loads(response.body)
        print(res['translateResult'][0][0]['tgt'])
        input("按任意键继续")