python3 [爬虫入门实战]scrapy爬取盘多多五百万数据并存mongoDB

偏执的太偏执、 2021-06-10 20:42 449阅读 0赞

### 总结：虽然是第二次爬取，但是多多少少还是遇到一些坑，总的结果还是好的，scrapy比多线程多进程强多了啊，中途没有一次被中断过。 ###

> 此版本是盘多多爬取数据的scrapy版本，涉及数据量较大，到现在已经是近500万的数据了。

### 1，抓取的内容 ###

![这里写图片描述][SouthEast]

主要爬取了：文件名，文件链接，文件类型，文件大小，文件浏览量，文件收录时间

### 一，scrapy中item.py代码 ###

# -*- 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 PanduoduoItem(scrapy.Item):
        # define the fields for your item here like:
        # name = scrapy.Field()
        # pass
        # 文件名称
        docName = scrapy.Field()
        # 文件链接
        docLink = scrapy.Field()
        # 文件分类
        docType = scrapy.Field()
        # 文件大小
        docSize = scrapy.Field()
        # 网盘类型
        docPTpye = scrapy.Field()
        # 浏览量
        docCount = scrapy.Field()
        # 收录时间
        docTime = scrapy.Field()

在spider进行抓取出现的问题，（1），因为没有设置请求头信息，盘多多浏览器会返回403错误，不让进行数据的爬取，所以这里我们要进行user-agent的设置，（settings.py中）

USER_AGENT = 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36'
    
    COOKIES_ENABLED = False
    
    ROBOTSTXT_OBEY = False

（2）直接在`def parse(self, response):`方法中打印`response.body`会返回不是utf8的编码，（无奈的是没有做相应的处理，还是爬出来了。）

### 二，spider里面的代码 ###

> （1），在spider中遇到的问题还是有的，比如table下的tbody标签获取，因为内容都被tbody包裹起来的，最后测试半小时，我们可以直接获取table下的tr标签就可以了。  
> （2），在tr下有多个不规则的td标签，我们可以直接根据td\[index\]来获取相对于的数据，

--------------------

贴上代码：

#encoding=utf8
    import scrapy
    from PanDuoDuo.items import PanduoduoItem
    
    class Panduoduo(scrapy.Spider):
        name = 'panduoduo'
        allowed_domains =['panduoduo.net']
        start_urls = ['http://www.panduoduo.net/c/4/{}'.format(n) for n in range(1,86151)]#6151
        # start_urls = ['http://www.panduoduo.net/c/4/1']#6151
        def parse(self, response):
            base_url = 'http://www.panduoduo.net'
            # print(str(response.body).encode('utf-8'))
            node_list = response.xpath("//div[@class='ca-page']/table[@class='list-resource']")
            node_list = response.xpath("//table[@class='list-resource']/tr")
            # print(node_list)
            for node  in node_list:
                duoItem = PanduoduoItem()
                title = node.xpath("./td[@class='t1']/a/text()").extract()
                print(title)
                duoItem['docName'] = ''.join(title)
                link = node.xpath("./td[@class='t1']/a/@href").extract()
                linkUrl  = base_url+''.join(link)
                duoItem['docLink'] = linkUrl
                print(linkUrl)
                docType = node.xpath("./td[2]/a/text()").extract()
                duoItem['docType'] = ''.join(docType)
                print(docType)
                docSize = node.xpath("./td[@class='t2']/text()").extract()
                print(docSize)
                duoItem['docSize'] = ''.join(docSize)
                docCount = node.xpath("./td[5]/text()").extract()
                docTime = node.xpath("./td[6]/text()").extract()
                duoItem['docCount'] = ''.join(docCount)
                duoItem['docTime'] = ''.join(docTime)
                print(docCount)
                print(docTime)
                yield duoItem

### （3）piplines.py里面的代码 ###

> 在这里主要进行了存入mongodb的操作和写入json文件的操作，不过现在看来，存入json文件确实是多余的，因为数据量确实大了。（在存入mongodb的时候遇到过存入报错的问题，这时候可能是mongodb被占用的问题，把原来的进行删除再重新运行一遍就行了。）

**代码：**

# -*- coding: utf-8 -*-
    
    # Define your item pipelines here
    #
    # Don't forget to add your pipeline to the ITEM_PIPELINES setting
    # See: http://doc.scrapy.org/en/latest/topics/item-pipeline.html
    import json
    import pymongo
    from scrapy.conf import settings
    
    class PanduoduoPipeline(object):
        def process_item(self, item, spider):
            return item
    
    class DuoDuoMongo(object):
        def __init__(self):
            self.client = pymongo.MongoClient(host=settings['MONGO_HOST'], port=settings['MONGO_PORT'])
            self.db = self.client[settings['MONGO_DB']]
            self.post = self.db[settings['MONGO_COLL']]
    
        def process_item(self, item, spider):
            postItem = dict(item)
            self.post.insert(postItem)
            return item
    
    # 写入json文件
    class JsonWritePipline(object):
        def __init__(self):
            self.file = open('盘多多.json','w',encoding='utf-8')
    
        def process_item(self,item,spider):
            line  = json.dumps(dict(item),ensure_ascii=False)+"\n"
            self.file.write(line)
            return item
    
        def spider_closed(self,spider):
            self.file.close()

最后附上settings里面的代码，这里的没有用到代理词，浏览器什么的，所以暂时不用设置middlewares.py里面的文件  
**settings代码：**

# -*- coding: utf-8 -*-
    
    # Scrapy settings for PanDuoDuo 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 = 'PanDuoDuo'
    
    SPIDER_MODULES = ['PanDuoDuo.spiders']
    NEWSPIDER_MODULE = 'PanDuoDuo.spiders'
    
    
    # Crawl responsibly by identifying yourself (and your website) on the user-agent
    # USER_AGENT = 'PanDuoDuo (+http://www.yourdomain.com)'
    USER_AGENT = 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36'
    
    # Obey robots.txt rules
    ROBOTSTXT_OBEY = False
    # 配置mongoDB
    MONGO_HOST = "127.0.0.1"  # 主机IP
    MONGO_PORT = 27017  # 端口号
    MONGO_DB = "PanDuo"  # 库名
    MONGO_COLL = "pan_duo"  # collection
    
    # 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
    
    # Disable cookies (enabled by default)
    COOKIES_ENABLED = False
    
    # Disable Telnet Console (enabled by default)
    #TELNETCONSOLE_ENABLED = False
    
    # Override the default request headers:
    #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 = { 
    # 'PanDuoDuo.middlewares.PanduoduoSpiderMiddleware': 543,
    #}
    
    # Enable or disable downloader middlewares
    # See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html
    #DOWNLOADER_MIDDLEWARES = { 
    # 'PanDuoDuo.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 = {
       # 'PanDuoDuo.pipelines.PanduoduoPipeline': 300,
       'PanDuoDuo.pipelines.DuoDuoMongo': 300,
       'PanDuoDuo.pipelines.JsonWritePipline': 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'

最后再看一下数据库里面的数据：

![这里写图片描述][SouthEast 1]

### 再看一下现在的总数，还在继续爬取哦，从下午1:00左右爬的应该是， ###

![这里写图片描述][SouthEast 2]

到此end，下次学习任务，一定把模拟登陆搞懂了。

[SouthEast]: /images/20210529/fe71b49010ae4a9ca6e84c97bf6df3b2.png
[SouthEast 1]: /images/20210529/824553f97f914f9596b231749015290f.png
[SouthEast 2]: /images/20210529/f1450ed04496481cbef15a558b6633cc.png