前一篇寫了基礎的爬蟲变泄，這篇我們就來爬圖片保存下來劳澄。?環(huán)境如上一篇scrapy 爬電影 抓取數(shù)據(jù)
Step1
首先還是實體類寫好我們需要的字段
注釋中ImagesPipeline后面會解釋
from scrapy import Item, Field
class PaimgItem(Item):
# 這兩個字段 image_urls images是ImagesPipeline存放需要的
image_urls = Field()
images = Field()
name = Field()
Step2
項目結構不變，依然首先來寫我們的Spider
import scrapy
from scrapy.spiders import CrawlSpider
from PaImg.items import PaimgItem
class MeizituSpider(CrawlSpider):
name = "meizitu"
host = 'http://www.meizitu.com/'
start_urls = ['http://www.meizitu.com/a/sexy.html']
headers = {
'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
'Accept-Language': 'zh-CN,zh;q=0.8,en-US;q=0.5,en;q=0.3',
}
def parse(self, response):
nextPage = response.xpath(u'//div[@id="wp_page_numbers"]//a[text()="下一頁"]/@href').extract_first()
nextPage = self.host + nextPage
for p in response.xpath('//li[@class="wp-item"]//a/@href').extract():
# scrapy.Request再次請求獲取詳情html由parse_item解析
yield scrapy.Request(p, callback=self.parse_item)
yield scrapy.Request(nextPage, callback=self.parse)
def parse_item(self, response):
item = PaimgItem()
# 詳情中的圖片列表
item['image_urls'] = response.xpath("http://div[@id='picture']//img/@src").extract()
item['name'] = response.xpath("http://div[@id='picture']//img/@alt").extract()[0].split(u'糠悼，')[0]
return item
上一篇如果你認真看了寫了调卑，這一點代碼相信你一眼就看懂了杉编。如果不懂先看一下上一篇吧scrapy 爬電影 抓取數(shù)據(jù)
Step3
上面我們將詳情頁的圖片列表地址存儲保存了下來。我們需要一個專門下載每張圖片的類赌厅。
也就是Step1中提到的ImagesPipeline穷绵。它是用來處理下載圖片的一個Pipeline關于Pipline可以查看Pipeline。我們創(chuàng)建一個PaimgPipeline類繼承自ImagesPipeline
class PaimgPipeline(ImagesPipeline):
我們需要復寫四個方法：get_media_requests(進行圖片下載請求處理) item_completed(圖片下載完成的通知) file_path(下載原始圖片的保存路徑) thumb_path(縮略圖保存路徑)
完整代碼：
headers = {
'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
'Accept-Language': 'zh-CN,zh;q=0.8,en-US;q=0.5,en;q=0.3',
"Referer": "https://www.meizitu.com/", # 加入referer 為下載的域名網(wǎng)站
}
class PaimgPipeline(ImagesPipeline):
# 在工作流程中可以看到特愿，管道會得到圖片的URL并從項目中下載仲墨。
# # 為了這么做，你需要重寫 get_media_requests() 方法揍障，并對各個圖片URL返回一個Request:
def get_media_requests(self, item, info):
for image_url in item['image_urls']:
# 這里把item傳過去目养，因為后面需要用item里面的name作為文件名
yield Request(image_url, meta={'item': item}, headers=headers)
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 file_path(self, request, response=None, info=None):
item = request.meta['item']
image_guid = request.url.split('/')[-1] # 倒數(shù)第一個元素
filenames = "full/%s/%s" % (item['name'], image_guid)
# print(filename)
return filenames
def thumb_path(self, request, thumb_id, response=None, info=None):
item = request.meta['item']
image_guid = request.url.split('/')[-1] # 倒數(shù)第一個元素
# thumb_id就是setting文件中定義的big small
filenames = "thumbil/%s/%s/%s" % (thumb_id, item['name'], image_guid)
return filenames
Step4
編寫隨機的UserAgent和IP代理
import random
from scrapy.downloadermiddlewares.useragent import UserAgentMiddleware
'''
這個類主要用于產(chǎn)生隨機UserAgent
'''
class RandomUserAgent(UserAgentMiddleware):
def __init__(self, agents):
self.agents = agents
@classmethod
def from_crawler(cls, crawler):
return cls(crawler.settings.getlist('USER_AGENTS')) # 返回的是本類的實例cls ==RandomUserAgent
def process_request(self, request, spider):
request.headers.setdefault('User-Agent', random.choice(self.agents))
import random
from PaImg.settings import IPPOOL
class ProxiesMiddleware(object):
def __init__(self, ip=''):
self.ip = ip
def process_request(self, request, spider):
thisip = random.choice(IPPOOL)
print("this is ip:" + thisip["ipaddr"])
request.meta["proxy"] = "http://" + thisip["ipaddr"]
Step5
下來我們就需要配置一下settings.py了。
- 首先我們先把剛剛寫的
PaimgPipeline配置到settings中
ITEM_PIPELINES = {
'PaImg.pipelines.PaimgPipeline': 300,
}
- 設置上面編寫的
RandomUserAgent及ProxiesMiddleware
DOWNLOADER_MIDDLEWARES = {
'scrapy.downloadermiddlewares.useragent.UserAgentMiddleware': None,
'PaImg.RandomUserAgent.RandomUserAgent': 100,
# 代理IP可能會失效 需要重新ping代理ip地址
'scrapy.downloadermiddlewares.httpproxy.HttpProxyMiddleware' : None,
'PaImg.ProxiesMiddleware.ProxiesMiddleware' : 100
}
- 設置USER_AGENTS毒嫡，也就是上面我們自己編寫
RandomUserAgent需要的數(shù)據(jù)
USER_AGENTS = [
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; AcooBrowser; .NET CLR 1.1.4322; .NET CLR 2.0.50727)",
"Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; Acoo Browser; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.0.04506)",
"Mozilla/4.0 (compatible; MSIE 7.0; AOL 9.5; AOLBuild 4337.35; Windows NT 5.1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)",
"Mozilla/5.0 (Windows; U; MSIE 9.0; Windows NT 9.0; en-US)",
"Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Win64; x64; Trident/5.0; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 2.0.50727; Media Center PC 6.0)",
"Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 1.0.3705; .NET CLR 1.1.4322)",
"Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.2; .NET CLR 1.1.4322; .NET CLR 2.0.50727; InfoPath.2; .NET CLR 3.0.04506.30)",
"Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN) AppleWebKit/523.15 (KHTML, like Gecko, Safari/419.3) Arora/0.3 (Change: 287 c9dfb30)",
"Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/527+ (KHTML, like Gecko, Safari/419.3) Arora/0.6",
"Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.2pre) Gecko/20070215 K-Ninja/2.1.1",
"Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9) Gecko/20080705 Firefox/3.0 Kapiko/3.0",
"Mozilla/5.0 (X11; Linux i686; U;) Gecko/20070322 Kazehakase/0.4.5",
"Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.8) Gecko Fedora/1.9.0.8-1.fc10 Kazehakase/0.5.6",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.56 Safari/535.11",
"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_3) AppleWebKit/535.20 (KHTML, like Gecko) Chrome/19.0.1036.7 Safari/535.20",
"Opera/9.80 (Macintosh; Intel Mac OS X 10.6.8; U; fr) Presto/2.9.168 Version/11.52",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.11 TaoBrowser/2.0 Safari/536.11",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/21.0.1180.71 Safari/537.1 LBBROWSER",
"Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E; LBBROWSER)",
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; QQDownload 732; .NET4.0C; .NET4.0E; LBBROWSER)",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.84 Safari/535.11 LBBROWSER",
"Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E)",
"Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E; QQBrowser/7.0.3698.400)",
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; QQDownload 732; .NET4.0C; .NET4.0E)",
"Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; SV1; QQDownload 732; .NET4.0C; .NET4.0E; 360SE)",
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; QQDownload 732; .NET4.0C; .NET4.0E)",
"Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E)",
"Mozilla/5.0 (Windows NT 5.1) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/21.0.1180.89 Safari/537.1",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/21.0.1180.89 Safari/537.1",
"Mozilla/5.0 (iPad; U; CPU OS 4_2_1 like Mac OS X; zh-cn) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8C148 Safari/6533.18.5",
"Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:2.0b13pre) Gecko/20110307 Firefox/4.0b13pre",
"Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:16.0) Gecko/20100101 Firefox/16.0",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.64 Safari/537.11",
"Mozilla/5.0 (X11; U; Linux x86_64; zh-CN; rv:1.9.2.10) Gecko/20100922 Ubuntu/10.10 (maverick) Firefox/3.6.10"
]
- 設置IPPOOL癌蚁，也就是上面我們自己編寫
ProxiesMiddleware需要的數(shù)據(jù)( 代理IP可能會失效 需要重新ping代理ip地址)
IPPOOL=[
{"ipaddr":"211.142.141.210:8998"},
{"ipaddr":"58.19.15.218:808"},
{"ipaddr":"117.90.1.141:9000"},
{"ipaddr":"125.117.115.180:9000"},
{"ipaddr":"211.142.141.210:8998"},
{"ipaddr":"163.125.251.242:8118"}
]
- 設置上面略縮圖的大小，有兩種方式：
IMAGES_THUMBS = {
'small': (50, 50),
'big': (270, 270),
}
- 設置圖片(寬最小與高最小)過濾兜畸。以防止我們會下載一些廣告圖或其他無用圖
IMAGES_MIN_HEIGHT = 110
IMAGES_MIN_WIDTH = 110
- 設置本地保存路徑
IMAGES_STORE = '/Users/cuiyang/Pictures/meizitu'
- 還有我們的延遲下載
DOWNLOAD_DELAY = 2
基本上這些就已經(jīng)夠了努释，我們還可以再優(yōu)化一下配置，也是比較通用的一些配置
Tip
- 減少超時時間以提高爬取速度
DOWNLOAD_TIMEOUT = 15
- 不對失敗的HTTP請求進行重試
RETRY_ENABLED = False
- 禁用cookie
COOKIES_ENABLED = False
- 通用爬取經(jīng)常抓取大量的 “index” 頁面膳叨； AjaxCrawlMiddleware能幫助您正確地爬取洽洁。 由于有些性能問題，且對于特定爬蟲沒有什么意義菲嘴，該中間默認關閉饿自。
AJAXCRAWL_ENABLED = False
