上周用了一周的时间学习了Python和Scrapy，实现了从0到1完整的网页爬虫实现。研究的时候很痛苦，但是很享受，做技术的嘛。
首先，安装Python，坑太多了，一个个爬。由于我是windows环境，没钱买mac, 在安装的时候遇到各种各样的问题，确实各种各样的依赖。
安装教程不再赘述。如果在安装的过程中遇到 ERROR：需要windows c/c++问题，一般是由于缺少windows开发编译环境，晚上大多数教程是安装一个VisualStudio，太不靠谱了，事实上只要安装一个WindowsSDK就可以了。
下面贴上我的爬虫代码：
爬虫主程序：
# -*- coding: utf-8 -*-import scrapyfrom scrapy.http import Requestfrom zjf.FsmzItems import FsmzItemfrom scrapy.selector import Selector# 圈圈：情感生活class MySpider(scrapy.Spider): #爬虫名 name = "MySpider" #设定域名 allowed_domains = ["nvsheng.com"] #爬取地址 start_urls = [] #flag x = 0 #爬取方法 def parse(self, response): item = FsmzItem() sel = Selector(response) item['title'] = sel.xpath('//h1/text()').extract() item['text'] = sel.xpath('//*[@class="content"]/p/text()').extract() item['imags'] = sel.xpath('//div[@id="content"]/p/a/img/@src|//div[@id="content"]/p/img/@src').extract() if MySpider.x == 0: page_list = MySpider.getUrl(self,response) for page_single in page_list: yield Request(page_single) MySpider.x += 1 yield item #init: 动态传入参数 #命令行传参写法： scrapy crawl MySpider -a start_url="http://some_url" def __init__(self,*args,**kwargs): super(MySpider,self).__init__(*args,**kwargs) self.start_urls = [kwargs.get('start_url')] def getUrl(self, response): url_list = [] select = Selector(response) page_list_tmp = select.xpath('//div[@class="viewnewpages"]/a[not(@class="next")]/@href').extract() for page_tmp in page_list_tmp: if page_tmp not in url_list: url_list.append("http://www.nvsheng.com/emotion/px/" + page_tmp) return url_list PipeLines类
# -*- 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.htmlfrom zjf import settingsimport json,os,re,randomimport urllib.requestimport requests, jsonfrom requests_toolbelt.multipart.encoder import MultipartEncoderclass MyPipeline(object): flag = 1 post_title = '' post_text = [] post_text_imageUrl_list = [] cs = [] user_id= '' def __init__(self): MyPipeline.user_id = MyPipeline.getRandomUser('37619,18441390,18441391') #process the data def process_item(self, item, spider): #获取随机user_id，模拟发帖 user_id = MyPipeline.user_id #获取正文text_str_tmp text = item['text'] text_str_tmp = "" for str in text: text_str_tmp = text_str_tmp + str # print(text_str_tmp) #获取标题 if MyPipeline.flag == 1: MyPipeline.post_title = MyPipeline.post_title + title[0] #保存并上传图片 text_insert_pic = '' text_insert_pic_w = '' text_insert_pic_h = '' for imag_url in item['imags']: img_name = imag_url.replace('/','').replace('.','').replace('|','').replace(':','') pic_dir = settings.IMAGES_STORE + '%s.jpg' %(img_name) urllib.request.urlretrieve(imag_url,pic_dir) #图片上传，返回json upload_img_result = MyPipeline.uploadImage(pic_dir,'image/jpeg') #获取json中保存图片路径 text_insert_pic = upload_img_result['result']['image_url'] text_insert_pic_w = upload_img_result['result']['w'] text_insert_pic_h = upload_img_result['result']['h'] #拼接json if MyPipeline.flag == 1: cs_json = {"c":text_str_tmp,"i":"","w":text_insert_pic_w,"h":text_insert_pic_h} else: cs_json = {"c":text_str_tmp,"i":text_insert_pic,"w":text_insert_pic_w,"h":text_insert_pic_h} MyPipeline.cs.append(cs_json) MyPipeline.flag += 1 return item #spider开启时被调用 def open_spider(self,spider): pass #sipder 关闭时被调用 def close_spider(self,spider): strcs = json.dumps(MyPipeline.cs) jsonData = {"apisign":"99ea3eda4b45549162c4a741d58baa60","user_id":MyPipeline.user_id,"gid":30,"t":MyPipeline.post_title,"cs":strcs} MyPipeline.uploadPost(jsonData) #上传图片 def uploadImage(img_path,content_type): "uploadImage functions" #UPLOAD_IMG_URL = "http://api.qa.douguo.net/robot/uploadpostimage" UPLOAD_IMG_URL = "http://api.douguo.net/robot/uploadpostimage" # 传图片 #imgPath = 'D:/pics/http___img_nvsheng_com_uploads_allimg_170119_18-1f1191g440_jpg.jpg' m = MultipartEncoder( # fields={'user_id': '192323', # 'images': ('filename', open(imgPath, 'rb'), 'image/JPEG')} fields={'user_id': MyPipeline.user_id, 'apisign':'99ea3eda4b45549162c4a741d58baa60', 'image': ('filename', open(img_path , 'rb'),'image/jpeg')} ) r = requests.post(UPLOAD_IMG_URL,data=m,headers={'Content-Type': m.content_type}) return r.json() def uploadPost(jsonData): CREATE_POST_URL = http://api.douguo.net/robot/uploadimagespost reqPost = requests.post(CREATE_POST_URL,data=jsonData)
def getRandomUser(userStr): user_list = [] user_chooesd = '' for user_id in str(userStr).split(','): user_list.append(user_id) userId_idx = random.randint(1,len(user_list)) user_chooesd = user_list[userId_idx-1] return user_chooesd 字段保存Items类
# -*- 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 FsmzItem(scrapy.Item): # define the fields for your item here like: # name = scrapy.Field() #tutor = scrapy.Field() #strongText = scrapy.Field() text = scrapy.Field() imags = scrapy.Field()
在命令行里键入
scrapy crawl MySpider -a start_url=www.aaa.com
这样就可以爬取aaa.com下的内容了
以上这篇Python下使用Scrapy爬取网页内容的实例就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持VEVB武林网。
注：相关教程知识阅读请移步到python教程频道。
