首先创建一个爬虫文件dgrds.py

–– coding: utf-8 ––

import scrapy

from scrapy_redis.spiders import RedisSpider

class DgrdsSpider(RedisSpider):

name = ‘dgrds’

redis_key = ‘dgrds:start_urls’

def parse(self, response):

for i in range(2499930, 2499940):

yield scrapy.Request(‘https://www.douguo.com/cookbook/’ + str(i) + ‘.html’, callback=self.parse2)

def parse2(self, response):

if (response.status == 200):

title = response.css(‘.rinfo h1.title::text’).get(”)

view_nums = response.css(‘.vcnum span:first-of-type::text’).get(”)

collection_nums = response.css(‘.vcnum .collectnum::text’).get(”)

user_name = response.css(‘.author-info .nickname::text’).get(”)

user_image = response.css(‘.author-img img::attr(src)’).get(”)

tags = ”

tag_arr = response.css(‘.fenlei span’)

if tag_arr is not None:

for tg in tag_arr:

tags += ‘;’ + tg.css(‘a::text’).get(”)

basic_url = ”

youku = ”

id = 0

isvideo = response.css(‘#banner + a’)

if isvideo is not None:

next_url = response.css(‘#banner + a::attr(href)’).get(”)

id = next_url.replace(‘/recipevideo/’, ”)

basic_url = ‘https://www.douguo.com/cookbook/’ + id + ‘.html’

item = {

‘cate’: ”,

‘title’: title,

‘view_nums’: view_nums,

‘collection_nums’: collection_nums,

‘user_name’: user_name,

‘user_image’: user_image,

‘tags’: tags,

‘basic_url’: basic_url

}

yield scrapy.Request(response.urljoin(next_url), meta=item, callback=self.parse4)

def parse4(self, response):

url = response.css(’embed::attr(src)’).get(”)

item = {

‘cate’: response.meta[‘cate’],

‘title’: response.meta[‘title’],

‘view_nums’: response.meta[‘view_nums’],

‘collection_nums’: response.meta[‘collection_nums’],

‘user_name’: response.meta[‘user_name’],

‘user_image’: response.meta[‘user_image’],

‘tags’: response.meta[‘tags’],

‘basic_url’: response.meta[‘basic_url’]

}

item[‘video_url’] = url

yield item

然后修改setting.py配置文件

–– coding: utf-8 ––

Scrapy settings for dgredis project

For simplicity, this file contains only settings considered important or

commonly used. You can find more settings consulting the documentation:

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

https://docs.scrapy.org/en/latest/topics/downloader-middleware.html

https://docs.scrapy.org/en/latest/topics/spider-middleware.html

BOT_NAME = ‘dgredis’

SPIDER_MODULES = [‘dgredis.spiders’]

NEWSPIDER_MODULE = ‘dgredis.spiders’

Crawl responsibly by identifying yourself (and your website) on the user-agent

USER_AGENT = ‘dgredis (+http://www.yourdomain.com)’

Obey robots.txt rules

ROBOTSTXT_OBEY = False

Configure maximum concurrent requests performed by Scrapy (default: 16)

CONCURRENT_REQUESTS = 32

Configure a delay for requests for the same website (default: 0)

See https://docs.scrapy.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 https://docs.scrapy.org/en/latest/topics/spider-middleware.html

SPIDER_MIDDLEWARES = {

‘dgredis.middlewares.DgredisSpiderMiddleware’: 543,

}

Enable or disable downloader middlewares

See https://docs.scrapy.org/en/latest/topics/downloader-middleware.html

DOWNLOADER_MIDDLEWARES = {

‘dgredis.middlewares.DgredisDownloaderMiddleware’: 543,

}

Enable or disable extensions

See https://docs.scrapy.org/en/latest/topics/extensions.html

EXTENSIONS = {

‘scrapy.extensions.telnet.TelnetConsole’: None,

}

Configure item pipelines

See https://docs.scrapy.org/en/latest/topics/item-pipeline.html

ITEM_PIPELINES = {

‘dgredis.pipelines.DgredisPipeline’: 300,

‘scrapy_redis.pipelines.RedisPipeline’: 400,

}

Enable and configure the AutoThrottle extension (disabled by default)

See https://docs.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 https://docs.scrapy.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’

MYSQL_HOST = ‘127.0.0.1’

MYSQL_PORT = ‘3306’

MYSQL_USER = ‘root’

MYSQL_PASS = ”

MYSQL_DB = ‘test’

HTTPERROR_ALLOWED_CODES = [404, 301]

DUPEFILTER_CLASS = “scrapy_redis.dupefilter.RFPDupeFilter”

SCHEDULER = “scrapy_redis.scheduler.Scheduler”

SCHEDULER_PERSIST = True

SCHEDULER_QUEUE_CLASS = “scrapy_redis.queue.SpiderPriorityQueue”

SCHEDULER_QUEUE_CLASS = “scrapy_redis.queue.SpiderQueue”

SCHEDULER_QUEUE_CLASS = “scrapy_redis.queue.SpiderStack”

LOG_LEVEL = ‘DEBUG’

Introduce an artifical delay to make use of parallelism. to speed up the

crawl.

DOWNLOAD_DELAY = 1

然后修改管道文件pipeline.py

–– coding: utf-8 ––

Define your item pipelines here

Don’t forget to add your pipeline to the ITEM_PIPELINES setting

See: https://docs.scrapy.org/en/latest/topics/item-pipeline.html

import pymysql

from twisted.enterprise import adbapi

class DgredisPipeline:

def init(self, dbpool):

self.dbpool = dbpool

@classmethod

def from_settings(cls, settings):

adbparams = dict(

host=settings[‘MYSQL_HOST’],

db=settings[‘MYSQL_DB’],

user=settings[‘MYSQL_USER’],

password=settings[‘MYSQL_PASS’],

charset=’utf8′,

cursorclass=pymysql.cursors.DictCursor

)

dbpool = adbapi.ConnectionPool(‘pymysql’, **adbparams)

return cls(dbpool)

def process_item(self, item, spider):

query = self.dbpool.runInteraction(self.do_insert, item) # 指定操作方法和操作数据

添加异常处理

query.addCallback(self.handle_error) # 处理异常

def do_insert(self, cursor, item):

对数据库进行插入操作，并不需要commit，twisted会自动commit

insert_sql = “””

insert into douguoaa(title,user_name,user_image,view_nums,collection_nums,basic_url,video_url,tags,cate_name) VALUES(%s,%s,%s,%s,%s,%s,%s,%s,%s)

“””

cursor.execute(insert_sql, (

item[‘title’], item[‘user_name’], item[‘user_image’], item[‘view_nums’], item[‘collection_nums’],

item[‘basic_url’],

item[‘video_url’], item[‘tags’], item[‘cate’]))

def handle_error(self, failure):

if failure:

print(failure)

修改完这三个文件就可以支持分布式爬取。去重。异步写入数据库功能了

cd切换到爬虫项目的spider文件夹，执行命令 scrapy runspider dgrds.py ,这时候爬虫出去等待发送指令状态

然后在redis-cli端发送爬取指令，也就是指定start_urls，命令：lpush dgrds:start_urls http://www.douguo.com，点击回车后上面的图片代码接收到指令后会自动执行爬取

这个是基础爬虫文件，规则爬取crawSpider跟这个类似，只需指定Rule规则即可

That’s All

Thanks！

原文链接:https://blog.csdn.net/muziduoxi/article/details/106422873

Original: https://blog.csdn.net/weixin_35204634/article/details/113128429
Author: 我有改名卡
Title: scrapy分布式写入到mysql_scrapy-redis分布式爬虫去重异步写入mysql数据库实例代码…