Breastcancer社区评论下载

首页

某个社区

某社区的一个话题

目标：获取这个网站所有话题的所有评论相关信息

python实现

# -*- coding: utf-8 -*-

"""
@Datetime: 2019/3/17
@Author: Zhang Yafei
"""
import functools
import os
import re
import traceback
import time
from concurrent.futures import ThreadPoolExecutor, wait, as_completed, ProcessPoolExecutor
from itertools import chain
from urllib.request import urljoin

import pandas as pd
from lxml import etree
from selenium import webdriver
from selenium.webdriver.chrome.options import Options

# 控制台输出所有列
pd.set_option('display.max_columns', None)

forum_info = pd.read_csv('all_forum_info.csv')


def timeit(fun):
    @functools.wraps(fun)
    def wrapper(*args, **kwargs):
        start_time = time.time()
        res = fun(*args, **kwargs)
        print('运行时间为%.6f' % (time.time() - start_time))
        return res

    return wrapper


class Download(object):
    """ 请求的下载 """

    def __init__(self, url):
        self.url = url
        self.forum_topic = '【{}】'.format(forum_info[forum_info.forum_url == url[0]].forum_topic.values[0])
        self.dir_path = os.path.join('download', self.forum_topic).replace('/', '-').replace(',', '').replace(':', '-').replace('"', '')
        if not os.path.exists(self.dir_path):
            os.mkdir(self.dir_path)
        self.chrome_options = Options()
        self.chrome_options.add_argument('--headless')
        self.chrome_options.add_argument('--disable-gpu')
        self.browser = None
        self.dispatch(pool=True)

    def dispatch(self, pool=True):
        """ 下载所有社区页面 """
        topic_count = int(self.url[1].replace(',', ''))
        pages = divmod(topic_count, 30)[0] + 1
        remain_pages = self.filter_url(pages)
        urls = [self.url[0] + '?page={}'.format(page) for page in remain_pages]
        # [self.forum_start(urls), list(map(self.forum_start, self.url))][len(self.url) > 1
        if urls and pool:
            pool = ThreadPoolExecutor(max_workers=4)
            pool.map(self.forum_start, urls, timeout=60)
            pool.shutdown()
        elif urls:
            list(map(self.forum_start, urls))
        else:
            print(self.dir_path + '共需下载{}页'.format(pages) + '	下载完成')

    def filter_url(self, pages):
        has_pages = list(map(lambda x: int(x.strip('.html')), os.listdir(self.dir_path)))
        down_pages = list(set(range(1, pages + 1)) - set(has_pages))
        if len(down_pages):
            print(self.dir_path + '共需下载：{}页'.format(pages) + ' 已下载：{}页'.format(len(has_pages)) + ' 未下载：{}页'.format(len(down_pages)))
        return down_pages

    def forum_start(self, url, header=False):
        if header:
            browser = webdriver.Chrome()
        else:
            browser = webdriver.Chrome(chrome_options=self.chrome_options)
        browser.get(url=url)
        html = browser.page_source
        browser.close()
        file_path = os.path.join(self.dir_path, url.split('?page=')[-1] + '.html')
        with open(file_path, mode='w', encoding='utf-8') as f:
            f.write(html)
        print(url + '下载成功')

    # def close(self):
    #     self.browser.close()


class BreastCancer(object):
    """ BreastCancer社区评论下载 """

    def __init__(self):
        self.base_url = 'https://community.breastcancer.org/'
        self.all_forum_columns = ['hgroup', 'forum_topic', 'forum_url', 'count_topic', 'count_post']
        self.all_forum_file = 'all_forum_info.csv'
        self.all_topic_columns = ['forum', 'topic_url', 'founder', 'count_posts', 'count_views', 'created_time', 'file_path']
        self.all_topic_file = 'all_topic_info.csv'

        if not os.path.exists(self.all_topic_file):
            self.write_to_file(columns=self.all_topic_columns, file=self.all_topic_file, mode='w')

    def download_forums_index(self):
        """
        下载社区首页
        """
        browser = webdriver.Chrome()
        browser.get(url=self.base_url)
        html = browser.page_source
        with open('download/community.html', mode='w', encoding='utf-8') as f:
            f.write(html)
        browser.close()

    def parse_forums_index(self):
        """ 解析社区首页 获取所有社区页面id """
        # 创建csv文件, 写入表头
        if not os.path.exists(self.all_forum_file):
            data = pd.DataFrame(columns=self.all_forum_columns)
            data.to_csv(self.all_forum_file, index=False)
        # 读取html文件,提取有用信息，写入到文件尾部
        with open('download/community.html', encoding='utf-8') as f:
            response = f.read()
        response = etree.HTML(response)
        rowgroups = response.xpath('//div[@class="rowgroup"]')
        list(map(self.get_all_forums_ids, rowgroups))

    def get_all_forums_ids(self, response):
        """
        获取所有:
            hgroup、
            forum_topic(社区主题)、
            url(社区页面地址)、
            count_topic(话题数量)、
            count_post(评论数量)
        """
        hgroup = response.xpath('.//h2/text()')[0]
        forums = response.xpath('.//li')
        data_list = []
        for forum in forums:
            forum_topic = forum.xpath('h3/a/text()')[0]
            forum_url = urljoin('https://community.breastcancer.org/', forum.xpath('h3/a/@href')[0])
            count_topic = forum.xpath('.//span[@class="count_topic"]/strong/text()')[0]
            count_post = forum.xpath('.//span[@class="count_post"]/strong/text()')[0]
            data_dict = {'hgroup': hgroup, 'forum_topic': forum_topic, 'forum_url': forum_url,
                         'count_topic': count_topic,
                         'count_post': count_post}
            data_list.append(data_dict)

        df = pd.DataFrame(data=data_list)
        # 固定输出列的顺序
        df = df.loc[:, self.all_forum_columns]
        df.to_csv(self.all_forum_file, index=False, header=False, mode='a')
        print(hgroup + '数据解析完成')

    def get_all_forum_page(self, pool=True):
        """ 获取所有社区url 并下载所有社区相关页面 """
        df = pd.read_csv(self.all_forum_file)
        forum_urls = df.apply(lambda x: (x.forum_url, x.count_topic), axis=1)
        if pool:
            # 多线程下载
            # BreastCancer.thread_pool_download(forum_urls)
            # 多进程
            BreastCancer.process_pool_download(forum_urls)
        else:
            # 单线程下载
            list(map(Download, forum_urls))

    @staticmethod
    def thread_pool_download(urls):
        """ 多线程下载 """
        pool = ThreadPoolExecutor(max_workers=4)
        tasks = [pool.submit(Download, url) for url in urls]
        wait(tasks)
        # pool.map(Download, urls)
        pool.shutdown()

    @staticmethod
    def process_pool_download(urls):
        """ 多进程下载 """
        pool = ProcessPoolExecutor(max_workers=4)
        pool.map(Download, urls)
        pool.shutdown()

    def get_topic_info(self, response):
        """ 获取所有话题相关信息 """
        topic_url = urljoin(self.base_url, response.xpath('./h3/a/@href')[0])
        count_posts = response.xpath('./p[1]/span[1]/strong/text()')[0]
        count_views = response.xpath('./p[1]/span[2]/strong/text()')[0]
        founder = response.xpath('./p[2]/a/text()')[0]
        created = response.xpath('./p[2]')[0].xpath('string(.)').replace('
', '').replace(' ', '')
        created_time = re.search('on(.*)', created).group(1)
        data_dict = {'topic_url': topic_url, 'founder': founder,
                     'count_posts': count_posts, 'count_views': count_views,
                     'created_time': created_time
                     }
        return data_dict

    @staticmethod
    def get_file_path_list(row):
        forum_topic = '【{}】'.format(row.forum_topic)
        dir_path = os.path.join('download', forum_topic).replace('/', '-').replace(',', '').replace(':', '-').replace(
            '"', '')
        file_path_list = list(map(lambda file: os.path.join(dir_path, file), os.listdir(dir_path)))
        return file_path_list

    @timeit
    def start_parse_forum_page(self, pool=False):
        """ 开始解析社区页面  """
        file_path_lists = forum_info.apply(BreastCancer.get_file_path_list, axis=1).tolist()
        file_path_lists = functools.reduce(lambda x, y: x + y, file_path_lists)
        # 每次解析前过滤已解析的页面
        file_path_lists = self.filter_file_path(file_path_lists)
        if pool:
            pool = ThreadPoolExecutor(max_workers=4)
            pool.map(self.parse_forum_page, file_path_lists)
            pool.shutdown()
        else:
            list(map(self.parse_forum_page, file_path_lists))

    def filter_file_path(self, file_path_list):
        parse_file = pd.read_csv(self.all_topic_file).file_path.unique()
        file_list = set(file_path_list) - set(parse_file)
        print('共{}个页面'.format(len(set(file_path_list))), '

已解析{}个页面'.format(len(set(parse_file))))
        return list(file_list)

    def parse_forum_page(self, file_path):
        """ 解析社区页面具体功能实现 """
        with open(file_path, encoding='utf-8') as f:
            response = f.read()
        response = etree.HTML(response)
        try:
            forum = response.xpath('//div[@id="section-content"]/h1/text()')[0]
            forum = re.search('Forum: (.*)', forum).group(1)
            topics = response.cssselect('#section-content > ul.rowgroup.topic-list > li')
            data_list = list(map(self.get_topic_info, topics))
            for data_dict in data_list:
                data_dict['forum'] = forum
                data_dict['file_path'] = file_path
            BreastCancer.write_to_file(data=data_list, file=self.all_topic_file, columns=self.all_topic_columns, mode='a')
            print(file_path + '解析完成')
        except Exception:
            traceback.print_exc()
            print(file_path + '解析错误')
            return

    @staticmethod
    def write_to_file(file, data=None, columns=None, mode=None, index=False, header=False):
        if mode == 'w':
            data = pd.DataFrame(columns=columns)
            data.to_csv(file, index=False)
        elif mode == 'a':
            df = pd.DataFrame(data=data)
            df = df.loc[:, columns]
            df.to_csv(file, mode=mode, index=index, header=header)

    @staticmethod
    def all_forum_stat():
        all_hgroup_count = forum_info.hgroup.nunique()
        all_forum_count = forum_info.forum_topic.nunique()
        all_topic_count = pd.to_numeric(forum_info.count_topic.str.replace(',', ''), downcast='integer').sum()
        all_post_count = pd.to_numeric(forum_info.count_post.str.replace(',', ''), downcast='integer').sum()
        all_topic_pages = forum_info.apply(lambda x: divmod(int(x.count_topic.replace(',', '')), 30)[0] + 1,
                                           axis=1).sum()
        print('共有hgroup：{}个'.format(all_hgroup_count))
        print('共有社区：{}个'.format(all_forum_count))
        print('共有话题：{}个'.format(all_topic_count))
        print('共有评论：{}个'.format(all_post_count))
        print('共需下载：{}个页面'.format(all_topic_pages))


if __name__ == '__main__':
    breastcancer = BreastCancer()
    # breastcancer.all_forum_stat()
    # 1. 下载社区首页
    # breastcancer.parse_forums_index()

    # 2. 获取所有社区页面url
    # breastcancer.get_all_forums_ids()

    # 3. 下载所有社区页面
    # breastcancer.get_all_forum_page(pool=False)

    # 4. 解析所有社区页面
    breastcancer.start_parse_forum_page()