python学習-scrapy爬虫類フレームワーク

Scrapyのインストールpip3 install Scrapy(mac版)
Scrapy爬虫類を作るには全部で4歩に分かれています

新規プロジェクト

目標を明確にする:あなたが登りたい目標を明確にする

爬虫類の作成:爬虫類の作成ページ

ストレージ内容:設計パイプストレージ爬取内容

コマンド詳細
インストール後、端末に直接scrapyを入力すると、バージョンといくつかのコマンドプロンプトが表示されます:scrapy bench:あなたのパソコンのscrapy性能をテストscrapy fetch + :URLアドレスにダウンロードページ情報を取得scrapy genspider scrapy runspider:爬虫類scrapy shellを作成/起動:環境を表示するvi settings.pyこのドキュメントを開く
ステップの詳細
新規プロジェクトscrapy startproject + は、自動的に多くのファイルを生成します.
生成ファイルコードの詳細:
items.py

# -*- coding: utf-8 -*-

# Define here the models for your scraped items
#
# See documentation in:
# http://doc.scrapy.org/en/latest/topics/items.html

import scrapy

class ItcastItem(scrapy.Item):   #       
    # define the fields for your item here like:
    # name = scrapy.Field()
    #     
    name = scrapy.Field()
    #     
    title = scrapy.Field()
    #     
    info = scrapy.Field()

settings.py

# -*- coding: utf-8 -*-

# Scrapy settings for ITcast project
#
# For simplicity, this file contains only settings considered important or
# commonly used. You can find more settings consulting the documentation:
#
#     http://doc.scrapy.org/en/latest/topics/settings.html
#     http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html
#     http://scrapy.readthedocs.org/en/latest/topics/spider-middleware.html

BOT_NAME = 'ITcast'

SPIDER_MODULES = ['ITcast.spiders']     #              
NEWSPIDER_MODULE = 'ITcast.spiders'

# Crawl responsibly by identifying yourself (and your website) on the user-agent
#USER_AGENT = 'ITcast (+http://www.yourdomain.com)'

# Obey robots.txt rules   #            robots   
ROBOTSTXT_OBEY = True

# Configure maximum concurrent requests performed by Scrapy (default: 16)
#CONCURRENT_REQUESTS = 32    #        

# Configure a delay for requests for the same website (default: 0)
# See http://scrapy.readthedocs.org/en/latest/topics/settings.html#download-delay
# See also autothrottle settings and docs
#DOWNLOAD_DELAY = 3     #     
# The download delay setting will honor only one of:
#CONCURRENT_REQUESTS_PER_DOMAIN = 16    #           
#CONCURRENT_REQUESTS_PER_IP = 16   #     ip  

# Disable cookies (enabled by default)
#COOKIES_ENABLED = False

# Disable Telnet Console (enabled by default)
#TELNETCONSOLE_ENABLED = False

# Override the default request headers:       #      header
#DEFAULT_REQUEST_HEADERS = {
#   'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
#   'Accept-Language': 'en',
#}

# Enable or disable spider middlewares
# See http://scrapy.readthedocs.org/en/latest/topics/spider-middleware.html
#SPIDER_MIDDLEWARES = {        #      
#    'ITcast.middlewares.ItcastSpiderMiddleware': 543,
#}

# Enable or disable downloader middlewares
# See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html
#DOWNLOADER_MIDDLEWARES = {     #      ，    
#    'ITcast.middlewares.MyCustomDownloaderMiddleware': 543,
#}

# Enable or disable extensions
# See http://scrapy.readthedocs.org/en/latest/topics/extensions.html
#EXTENSIONS = {   #     
#    'scrapy.extensions.telnet.TelnetConsole': None,
#}

# Configure item pipelines
# See http://scrapy.readthedocs.org/en/latest/topics/item-pipeline.html
#ITEM_PIPELINES = {    #       
#    'ITcast.pipelines.ItcastPipeline': 300,
#}

# Enable and configure the AutoThrottle extension (disabled by default)
# See http://doc.scrapy.org/en/latest/topics/autothrottle.html
#AUTOTHROTTLE_ENABLED = True
# The initial download delay
#AUTOTHROTTLE_START_DELAY = 5
# The maximum download delay to be set in case of high latencies
#AUTOTHROTTLE_MAX_DELAY = 60
# The average number of requests Scrapy should be sending in parallel to
# each remote server
#AUTOTHROTTLE_TARGET_CONCURRENCY = 1.0
# Enable showing throttling stats for every response received:
#AUTOTHROTTLE_DEBUG = False

# Enable and configure HTTP caching (disabled by default)
# See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html#httpcache-middleware-settings
#HTTPCACHE_ENABLED = True
#HTTPCACHE_EXPIRATION_SECS = 0
#HTTPCACHE_DIR = 'httpcache'
#HTTPCACHE_IGNORE_HTTP_CODES = []
#HTTPCACHE_STORAGE = 'scrapy.extensions.httpcache.FilesystemCacheStorage'

itcast.py

# -*- coding: utf-8 -*-
import scrapy
from ITcast.ITcast.items import ItcastItem

class ItcastSpider(scrapy.Spider):
    name = 'itcast'   #     ,            
    allowed_domains = ['itcast.cn']    #       ，           ,    
    start_urls = ['http://www.itcast.cn/channel/teacher.shtml']   #       ，        ,        

    def parse(self, response):    #      ，  url         
        node_list = response.xpath("//div[@class='li_txt']")
        items = []
        for node in node_list:

            item = ItcastItem()
            # .extract() xpath    Unicode     xpath        
            name = node.xpath("./h3/text()").extract()
            title = node.xpath("./h4/text()").extract()
            info = node.xpath("./p/text()").extract()

            item['name'] = name[0]
            item['title'] = title[0]
            item['info'] = info[0]
            items.append(item)
        return items