Python爬虫的scrapy框架的简单应用
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2022-05-06 20:32:32
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load_mzitu\mzitu\item.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 MzituItem(scrapy.Item):
# define the fields for your item here like:
# name = scrapy.Field()
name=scrapy.Field()
image_url=scrapy.Field()
url=scrapy.Field()
load_mzitu\mzitu\middlewares.py
# -*- coding: utf-8 -*-
# Define here the models for your spider middleware
#
# See documentation in:
# http://doc.scrapy.org/en/latest/topics/spider-middleware.html
from scrapy import signals
class MzituSpiderMiddleware(object):
# Not all methods need to be defined. If a method is not defined,
# scrapy acts as if the spider middleware does not modify the
# passed objects.
@classmethod
def from_crawler(cls, crawler):
# This method is used by Scrapy to create your spiders.
s = cls()
crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
return s
def process_spider_input(response, spider):
# Called for each response that goes through the spider
# middleware and into the spider.
# Should return None or raise an exception.
return None
def process_spider_output(response, result, spider):
# Called with the results returned from the Spider, after
# it has processed the response.
# Must return an iterable of Request, dict or Item objects.
for i in result:
yield i
def process_spider_exception(response, exception, spider):
# Called when a spider or process_spider_input() method
# (from other spider middleware) raises an exception.
# Should return either None or an iterable of Response, dict
# or Item objects.
pass
def process_start_requests(start_requests, spider):
# Called with the start requests of the spider, and works
# similarly to the process_spider_output() method, except
# that it doesn’t have a response associated.
# Must return only requests (not items).
for r in start_requests:
yield r
def spider_opened(self, spider):
spider.logger.info('Spider opened: %s' % spider.name)
#防盗链
class MeiZiTu(object):
def process_request(self, request, spider):
'''设置headers和切换请求头
:param request: 请求体
:param spider: spider对象
:return: None
'''
referer = request.meta.get('referer', None)
if referer:
request.headers['referer'] = referer
load_mzitu\mzitu\pipelines.py
# -*- 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
#图片管道
from scrapy.pipelines.images import ImagesPipeline
from scrapy.exceptions import DropItem
from scrapy import Request
import re
import urllib
import uuid
class MzituPipeline(ImagesPipeline):
#重写请求
def get_media_requests(self, item, info):
"""
:param item: spider.py中返回的item
:param info:
:return:
"""
# 这里的item['image_url'] 是前面的meizi.py返回的一个列表
for img_url in item['image_url']:
#这是每一套图总地址url 是前面的meizi.py返回的是一个字符串
referer=item['url']
x=uuid.uuid1()
urllib.urlretrieve(referer,'F:\scrapy\MZITU\%s.jpg' % x)
#这里的Request默认callback给file_path meta传递参数给 file_path
yield Request(img_url,meta={'item':item,'referer':referer})
# 重写文件路径
def file_path(self, request, response=None, info=None):
"""
:param request: 每一个图片下载管道请求
:param response:
:param info:
:param strip :清洗Windows系统的文件夹非法字符，避免无法创建目录
:return: 每套图的分类目录 传递到item_completed的results
"""
#接收来自get_media_requests的item 也就是meizi.py提交过来的 item
item=request.meta['item']
#得到每套图的名字（文件夹名）
file_name=item['name']
#因为得到的名字可能存在window系统非法的文件字符串 所以这里替换一下
file_name=strip(file_name)
#利用图片url的分割得到每张图片的名字
img_name=request.url.split('/')[-1]
#这里是结合起来得到的每一张图片的具体存取路径
file_img_path='full/{}/{}'.format(file_name,img_name)
#print file_img_path
return file_img_path
def item_completed(self, results, item, info):
image_paths = [x['path'] for ok, x in results if ok]
if not image_paths:
raise DropItem("Item contains no images")
return item
def strip(path):
"""
:param path: 需要清洗的文件夹名字
:return: 清洗掉Windows系统非法文件夹名字的字符串
"""
#找到 RE 匹配的所有子串，并将其用一个不同的字符串替换。可选参数 count 是模式匹配後替换的最大次数；count 必须是非负整数。
# 缺省值是 0 表示替换所有的匹配。如果无匹配，字符串将会无改变地返回 re.sub(pattern, repl, string, count=0, flags=0)
#这里非法字符用空''替换
path = re.sub(r'[？\\*|“<>:/]','', str(path))
return path
# def process_item(self, item, spider):
# return item
if __name__=="__main__":
#没什么意思 测试下strip好不好用
a = '我是一个？\*|“<>:/错误的字符串'
print(strip(a))
load_mzitu\mzitu\settings.py
# -*- coding: utf-8 -*-
# Scrapy settings for mzitu 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 = 'mzitu'
SPIDER_MODULES = ['mzitu.spiders']
NEWSPIDER_MODULE = 'mzitu.spiders'
# Crawl responsibly by identifying yourself (and your website) on the user-agent
#USER_AGENT = 'mzitu (+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 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 = {
# 'mzitu.middlewares.MzituSpiderMiddleware': 543,
#}
# Enable or disable downloader middlewares
# See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html
DOWNLOADER_MIDDLEWARES = {
'mzitu.middlewares.MeiZiTu':5,
}
# 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 = {
'mzitu.pipelines.MzituPipeline': 1.7,
}
IMAGES_STORE = 'F:/scrapy/load_mzitu/mztu'
# 30 days of delay for images expiration
IMAGES_EXPIRES = 10
# 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'
load_mzitu\mzitu\spiders\meizi .py
# -*- coding: utf-8 -*-
import scrapy
from mzitu.items import MzituItem
from scrapy.spiders import CrawlSpider,Rule
from scrapy.linkextractors import LinkExtractor
###这里千万要把parser函数删了 不然无法调用parser_item函数 因为CrawlSpider已经默认使用parser函数来爬取第一个链接
#该程序的目的就是找到所有的符合规律的url链接跟进获取图片
class MeiziSpider(CrawlSpider):
name = "meizi"
allowed_domains = ["mzitu.com"]
start_urls = ['http://www.mzitu.com/']
#定义一个全局的列表
img_urls=[]
#定义抓取规则 找到如下规则内的所有url allow是允许的 deny是不允许的 从start_url页，从start_urls链接的源代码开始找 然后再跟进继续使用该规则
rules = (
Rule(LinkExtractor(allow=('http://www.mzitu.com/\d{6}',),deny=('http://www.mzitu.com/\s',)),\
callback='parser_item',follow=True),
)
def parser_item(self,response):
item=MzituItem()
#得到没套图的名字 extract_first(default=”N/A”)取xpath返回值的第一个元素。如果xpath没有取到值，则返回N/A
#这里我用字符串分割的方法
name=response.selector.xpath('/html/body/div[2]/div[1]/div[1]/text()[3]').extract()
item['name']=name[0][3:-1]
item['url']=response.url
all_page=response.selector.xpath('/html/body/div[2]/div[1]/div[4]/a[5]/span/text()').extract()
for page in range(1,int(all_page[0])+1):
#得到每张照片的地址
url=response.url+'/'+str(page)
yield scrapy.Request(url=url,callback=self.img_url)
#上面的循环所有页面执行完 定义的图片url列表也在下面的 img_url函数里添加好了 所以放入容器
item['image_url']=self.img_urls
yield item
def img_url(self,response):
urls=response.selector.xpath('/html/body/div[2]/div[1]/div[3]/p/a/img/@src').extract()
#有的页面不只一张图 所以加个循环 得到当前页面所有的
print "--------------------------------------------------\n"
for img_url in urls:
#x=uuid.uuid1()
f =open("data.txt","a+")
f.write(img_url+"\n")
f.close()
print img_url+" ===>>download"
self.img_urls.append(img_url)
load_mzitu\begin.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# @Time : 2017/10/30 19:28
# @Author : Yu
# @Site :
# @File : begin.py
from scrapy import cmdline
cmdline.execute(["scrapy","crawl","meizi"])
#http://i.meizitu.net/2015/05/29m02.jpg
#http://www.mzitu.com/156427
运行begin后会把所有爬取到的图片链接写入到txt中
load_mzitu\download.py
import urllib
import urllib2
import requests
import random
import uuid,os
#img_url = "https://p.ssl.qhimg.com/dm/48_48_100/t017aee03b28107657b.jpg"
img_url="http://i.meizitu.net/2018/10/13c02.jpg"
img="http://i.meizitu.net/2018/11/06c35.jpg"
my_headers={
"User-Agent":"Mozilla/5.0 (Linux; Android 6.0; Nexus 5 Build/MRA58N) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Mobile Safari/537.36",
'Referer':'http://m.mzitu.com/15309'}
def read_txt(path):
mt=[]
f=open(path,'r')
for t in f.readlines():
mt.append(t)
f.close()
return mt
def down_load(img,my_headers):
request = urllib2.Request(url=img, headers=my_headers)
response = urllib2.urlopen(request)
pic=response.read()
path_name=img.split('/')[-1]
path_name=path_name.replace('\n','')
new_name="pic/" + path_name
if not os.path.exists(new_name):
with open("%s" % new_name, "wb") as f:
f.write(pic)
print "downloading with urllib"
def main():
path="data.txt"
mt=read_txt(path)
print len(mt)
print len(set(mt))
for f in mt:
print f
down_load(f,my_headers)
print 'fininsh'.center(40,'-')
main()
运行它会把txt中的图片下载到本地。
详情看gittup
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