摘要：
left_menu_text=requests.get（“https:csdn”）.textnodes_str_tatch=re.search（“forumNodes:”None“）nodes_list=ast.literal_eval（nodes_str）returnnodes_listreturn[]url_list=[]defprocess_nodes_list（nodes_list）：
安装软件：
pip instal pymysq
pip install peewee
创建数据模型orm
from peewee import * db = MySQLDatabase("spider", host="127.0.0.1", port=3306, user="root", password="root") class BaseModel(Model): class Meta: database = db #设计数据表的时候有几个重要点一定要注意 """ char类型， 要设置最大长度 对于无法确定最大长度的字段，可以设置为Text 设计表的时候 采集到的数据要尽量先做格式化处理 default和null=True """ class Topic(BaseModel): title = CharField() content = TextField(default="") id = IntegerField(primary_key=True) author = CharField() create_time = DateTimeField() answer_nums = IntegerField(default=0) click_nums = IntegerField(default=0) praised_nums = IntegerField(default=0) jtl = FloatField(default=0.0) # 结帖率 score = IntegerField(default=0) # 赏分 status = CharField() # 状态 last_answer_time = DateTimeField() class Answer(BaseModel): topic_id = IntegerField() author = CharField() content = TextField(default="") create_time = DateTimeField() parised_nums = IntegerField(default=0) #点赞数 class Author(BaseModel): name = CharField() id = CharField(primary_key=True) click_nums = IntegerField(default=0) #访问数 original_nums = IntegerField(default=0) #原创数 forward_nums = IntegerField(default=0) # 转发数 rate = IntegerField(default=-1) # 排名 answer_nums = IntegerField(default=0) # 评论数 parised_nums = IntegerField(default=0) # 获赞数 desc = TextField(null=True) industry = CharField(null=True) location = CharField(null=True) follower_nums = IntegerField(default=0) # 粉丝数 following_nums = IntegerField(default=0) # 关注数 if __name__ == "__main__": db.create_tables([Topic, Answer, Author])
数据爬取与解析：
""" 抓取 解析 存储 """ import re import ast from urllib import parse from datetime import datetime import requests from scrapy import Selector from csdn_spider.models import * domain = "https://bbs.csdn.net" def get_nodes_json(): left_menu_text = requests.get("https://bbs.csdn.net/dynamic_js/left_menu.js?csdn").text nodes_str_match = re.search("forumNodes: (.*])", left_menu_text) if nodes_str_match: nodes_str = nodes_str_match.group(1).replace("null", "None") nodes_list = ast.literal_eval(nodes_str) return nodes_list return [] url_list = [] def process_nodes_list(nodes_list): #将js的格式提取出url到list中 for item in nodes_list: if "url" in item: if item["url"]: url_list.append(item["url"]) if "children" in item: process_nodes_list(item["children"]) def get_level1_list(nodes_list): level1_url = [] for item in nodes_list: if "url" in item and item["url"]: level1_url.append(item["url"]) return level1_url def get_last_urls(): #获取最终需要抓取的url nodes_list = get_nodes_json() process_nodes_list(nodes_list) level1_url = get_level1_list(nodes_list) last_urls = [] for url in url_list: if url not in level1_url: last_urls.append(url) all_urls = [] for url in last_urls: all_urls.append(parse.urljoin(domain, url)) all_urls.append(parse.urljoin(domain, url+"/recommend")) all_urls.append(parse.urljoin(domain, url+"/closed")) return all_urls def parse_topic(url): #获取帖子的详情以及回复 topic_id = url.split("/")[-1] res_text = requests.get(url).text sel = Selector(text=res_text) all_divs = sel.xpath("//div[starts-with(@id, 'post-')]") topic_item = all_divs[0] content = topic_item.xpath(".//div[@class='post_body post_body_min_h']").extract()[0] praised_nums = topic_item.xpath(".//label[@class='red_praise digg']//em/text()").extract()[0] jtl_str = topic_item.xpath(".//div[@class='close_topic']/text()").extract()[0] jtl = 0 jtl_match = re.search("(d+)%", jtl_str) if jtl_match: jtl = int(jtl_match.group(1)) existed_topics = Topic.select().where(Topic.id == topic_id) if existed_topics: topic = existed_topics[0] topic.content = content topic.jtl = jtl topic.praised_nums = praised_nums topic.save() for answer_item in all_divs[1:]: answer = Answer() answer.topic_id = topic_id author_info = answer_item.xpath(".//div[@class='nick_name']//a[1]/@href").extract()[0] author_id = author_info.split("/")[-1] create_time = answer_item.xpath(".//label[@class='date_time']/text()").extract()[0] create_time = datetime.strptime(create_time, "%Y-%m-%d %H:%M:%S") answer.author = author_id answer.create_time = create_time praised_nums = topic_item.xpath(".//label[@class='red_praise digg']//em/text()").extract()[0] answer.parised_nums = int(praised_nums) content = topic_item.xpath(".//div[@class='post_body post_body_min_h']").extract()[0] answer.content = content answer.save() next_page = sel.xpath("//a[@class='pageliststy next_page']/@href").extract() if next_page: next_url = parse.urljoin(domain, next_page[0]) parse_topic(next_url) def parse_author(url): author_id = url.split("/")[-1] # 获取用户的详情 headers = { 'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:65.0) Gecko/20100101 Firefox/65.0', } res_text = requests.get(url, headers=headers).text sel = Selector(text=res_text) author = Author() author.id = author_id all_li_strs = sel.xpath("//ul[@class='mod_my_t clearfix']/li/span/text()").extract() click_nums = all_li_strs[0] original_nums = all_li_strs[1] forward_nums = int(all_li_strs[2]) rate = int(all_li_strs[3]) answer_nums = int(all_li_strs[4]) parised_nums = int(all_li_strs[5]) author.click_nums = click_nums author.original_nums = original_nums author.forward_nums = forward_nums author.rate = rate author.answer_nums = answer_nums author.parised_nums = parised_nums desc = sel.xpath("//dd[@class='user_desc']/text()").extract() if desc: author.desc = desc[0].strip() person_b = sel.xpath("//dd[@class='person_b']/ul/li") for item in person_b: item_text = "".join(item.extract()) if "csdnc-m-add" in item_text: location = item.xpath(".//span/text()").extract()[0].strip() author.location = location else: industry = item.xpath(".//span/text()").extract()[0].strip() author.industry = industry name = sel.xpath("//h4[@class='username']/text()").extract()[0] author.name = name.strip() existed_author = Author.select().where(Author.id == author_id) if existed_author: author.save() else: author.save(force_insert=True) def parse_list(url): res_text = requests.get(url).text sel = Selector(text=res_text) all_trs = sel.xpath("//table[@class='forums_tab_table']//tr")[2:] for tr in all_trs: topic = Topic() if tr.xpath(".//td[1]/span/text()").extract(): status = tr.xpath(".//td[1]/span/text()").extract()[0] topic.status = status if tr.xpath(".//td[2]/em/text()").extract(): score = tr.xpath(".//td[2]/em/text()").extract()[0] topic.score = int(score) topic_url = parse.urljoin(domain, tr.xpath(".//td[3]/a/@href").extract()[0]) topic_title = tr.xpath(".//td[3]/a/text()").extract()[0] author_url = parse.urljoin(domain,tr.xpath(".//td[4]/a/@href").extract()[0]) author_id = author_url.split("/")[-1] create_time = tr.xpath(".//td[4]/em/text()").extract()[0] create_time = datetime.strptime(create_time, "%Y-%m-%d %H:%M") answer_info = tr.xpath(".//td[5]/span/text()").extract()[0] answer_nums = answer_info.split("/")[0] click_nums = answer_info.split("/")[1] last_time_str = tr.xpath(".//td[6]/em/text()").extract()[0] last_time = datetime.strptime(last_time_str, "%Y-%m-%d %H:%M") topic.id = int(topic_url.split("/")[-1]) topic.title = topic_title topic.author = author_id topic.click_nums = int(click_nums) topic.answer_nums = int(answer_nums) topic.create_time = create_time topic.last_answer_time = last_time existed_topics = Topic.select().where(Topic.id==topic.id) if existed_topics: topic.save() else: topic.save(force_insert=True) parse_topic(topic_url) # parse_author(author_url) next_page = sel.xpath("//a[@class='pageliststy next_page']/@href").extract() if next_page: next_url = parse.urljoin(domain, next_page[0]) parse_list(next_url) if __name__ == "__main__": last_urls = get_last_urls() for url in last_urls: parse_list(url) print(last_urls)