# -*- coding: utf-8 -*-
# scrapy爬取全部知乎用户信息
# 1：是否遵守robbots_txt协议改为False
# 2: 加入爬取所需的headers: user-agent，authorazation
# 3：确定爬取任务：即想要得到的用户信息
# 4: 爬取思路解析
# 整体思路：从起始大v开始，获得其关注列表和粉丝列表；解析列表，可以得到每一个用户的详细信息地址，组成每一个用户的url；
# 从用户的url开始，解析用户详细信息，取到详细信息。同时又可以解析到每一个用户的关注列表和粉丝列表，循环请求。
# 分步骤如下：
# 4-1：找到起始大v，请求其页面，循环翻页获取其全部的关注列表，粉丝列表
# 4-2：列表步骤：解析关注列表，粉丝列表，从所有列表中取得用户的url_token，组成用户url，执行用户步骤4-3
# 4-3：用户步骤：解析用户url，该步骤可以获得1.该用户详细信息 2.该用户全部的关注列表与粉丝列表，返回列表步骤4-2
# 4-4：同步存储item到数据库mongodb，去重设计。
import json
import scrapy
from zhihu2.items import Zhihu2Item

class ZhihuuserSpider(scrapy.Spider):
    name = 'zhihuuser'
    allowed_domains = ['www.zhihu.com']
    start_urls = ['http://www.zhihu.com/']
    start_user = 'excited-vczh'
    # 一：对用户关注列表的请求构造
    # 用户关注列表 start_user为起始大v，followees_include为请求参数，limit为每页显示用户数，默认20，offset为页码参数，首页为0
    followees_url = 'https://www.zhihu.com/api/v4/members/{user}/followees?include={include}&offset={offset}&limit={limit}'
    followees_include = 'data[*].answer_count,articles_count,gender,follower_count,is_followed,is_following,badge[?(type=best_answerer)].topics'

    # 二：对用户粉丝列表的请求构造
    # 用户关注列表 start_user为起始大v，followees_include为请求参数，limit为每页显示用户数，默认20，offset为页码参数，首页为0
    followers_url = 'https://www.zhihu.com/api/v4/members/{user}/followers?include={include}&offset={offset}&limit={limit}'
    followers_include = 'data[*].answer_count,articles_count,gender,follower_count,is_followed,is_following,badge[?(type=best_answerer)].topics'

    # 三：对用户详细信息的请求构造
    user_url = 'https://www.zhihu.com/api/v4/members/{user}?include={include}'
    user_include = 'allow_message,is_followed,is_following,is_org,is_blocking,employments,answer_count,follower_count,articles_count,gender,badge[?(type=best_answerer)].topics'
    def start_requests(self):
        # 分别举列表url和用户url示例，以验证是否能够爬取
        # 关注列表url示例
        # 返回401是请求验证用户的身份，知乎的首页是要求验证用户的身份才能进入，所以需要在settings里面设置authorization
        # url='https://www.zhihu.com/api/v4/members/excited-vczh/followees?include=data%5B*%5D.answer_count%2Carticles_count%2Cgender%2Cfollower_count%2Cis_followed%2Cis_following%2Cbadge%5B%3F(type%3Dbest_answerer)%5D.topics&offset=60&limit=20'
        # 用户详细url示例
        # url='https://www.zhihu.com/api/v4/members/lanfengxing?include=allow_message%2Cis_followed%2Cis_following%2Cis_org%2Cis_blocking%2Cemployments%2Canswer_count%2Cfollower_count%2Carticles_count%2Cgender%2Cbadge%5B%3F(type%3Dbest_answerer)%5D.topics'
        # yield scrapy.Request(url, callback=self.parse)
        # 构造用户关注列表的请求 主要用到format方法

        yield scrapy.Request(url=self.followees_url.format(user=self.start_user, include=self.followees_include, offset=0, limit=20), callback=self.parse_followees)
        # 构造用户粉丝列表的请求 主要用到format方法
        yield scrapy.Request(url=self.followers_url.format(user=self.start_user, include=self.followers_include, offset=0, limit=20),callback=self.parse_followers)
        # 对用户详细信息的请求构造
        yield scrapy.Request(url=self.user_url.format(user=self.start_user, include=self.user_include),callback=self.parse_user)
    # 解析关注列表
    def parse_followees(self, response):
        results = json.loads(response.text)
        if 'data' in results.keys():
            for result in results.get('data'):
                # 解析关注列表，得到所关注人的url_token，构造解析详细信息请求
                yield scrapy.Request(url=self.user_url.format(user=result.get('url_token'), include=self.user_include),callback=self.parse_user)
        # 构造翻页请求
        if 'paging' in results.keys() and results.get('paging').get('is_end')==False:
            next = results.get('paging').get('next')
            yield scrapy.Request(url=next, callback=self.parse_followees)

    # 解析粉丝列表
    def parse_followers(self, response):
        results = json.loads(response.text)
        if 'data' in results.keys():
            for result in results.get('data'):
                # 解析关注列表，得到所关注人的url_token，构造解析详细信息请求
                yield scrapy.Request(url=self.user_url.format(user=result.get('url_token'), include=self.user_include),
                                     callback=self.parse_user)
        # 构造翻页请求
        if 'paging' in results.keys() and results.get('paging').get('is_end') == False:
            next = results.get('paging').get('next')
            yield scrapy.Request(url=next, callback=self.parse_followers)

    # 解析用户详细信息,由于我们任务的目标是获取用户详细信息，因此在这一步要确定哪些信息是被使用，在items里面做相应设置
    def parse_user(self, response):
        item = Zhihu2Item()
        # 返回的response是json格式，因此需要解析json
        results = json.loads(response.text)
        # 遍历item数据结构的键名，item.field可以得到数据结构的所有键
        for field in item.fields:
            # 如果item的键名在网页里面，则遍历赋值
            if field in results.keys():
                item[field]=results.get(field)
        yield item

        # 提取用户的关注列表
        yield scrapy.Request(url=self.followees_url.format(user=results.get('url_token'),include = self.followees_include,offset=0, limit=20),callback=self.parse_followees)
        # 提取用户的粉丝列表
        yield scrapy.Request(url=self.followers_url.format(user=results.get('url_token'), include=self.followers_include, offset=0, limit=20),callback=self.parse_followers)

# -*- 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

# 想要获取的用户信息设置
class Zhihu2Item(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()

    # 姓名　
    name = scrapy.Field()
    # 性别
    gender = scrapy.Field()
    # 职业
    employments = scrapy.Field()
    # 级别
    badge = scrapy.Field()
    # 一句话介绍
    headline = scrapy.Field()
    # 粉丝数
    follower_count = scrapy.Field()
    # 回答问题数
    answer_count = scrapy.Field()
    # 撰写文章数
    articles_count = scrapy.Field()
    # 头像
    avatar_url = scrapy.Field()
    avatar_url_template = scrapy.Field()
    # id
    id = scrapy.Field()
    # 注册类型
    type = scrapy.Field()
    # 注册url
    url = scrapy.Field()
    # 主页地址，唯一识别码
    url_token = scrapy.Field()
    # 用户类型
    user_type = scrapy.Field()

# -*- 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
import pymongo
# 项目管道用来处理得到的item信息,这里设置存储到MongoDB的class
class MongoPipeline(object):

    #初始化变量, 这里需要传入mongo_uri,mongo_db两个参数,这两个参数可以从类方法里面获得
    def __init__(self,mongo_uri,mongo_db):
        self.mongo_uri = mongo_uri
        self.mongo_db = mongo_db

    # 定义类方法,获得mongo_uri,mongo_db
    @classmethod
    def from_crawler(cls,crawler):
        return cls(
        mongo_uri = crawler.settings.get('MONGO_URI'),
        mongo_db = crawler.settings.get('MONGO_DB')
        )

    # 初始化mongodb的变量,client, 与db,爬虫启动时即开始初始化
    def open_spider(self,spider):
        self.client = pymongo.MongoClient(self.mongo_uri)
        self.db = self.client[self.mongo_db]

    # 存储主体进程,返回item或者DropItem,这里设置update方法设置去重, 如果有同名就更新,没有就重新建立
    def process_item(self, item, spider):
        name = item.__class__.__name__
        self.db[name].update({'url_token':item['url_token']}, {'$set':item}, True)
        return item

    # 关闭mongodb
    def close_spider(self,spider):
        self.client.close()

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

# Scrapy settings for zhihu2 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 = 'zhihu2'

SPIDER_MODULES = ['zhihu2.spiders']
NEWSPIDER_MODULE = 'zhihu2.spiders'

MONGO_URI = 'localhost'
MONGO_DB = 'zhihu2'
# Crawl responsibly by identifying yourself (and your website) on the user-agent
#USER_AGENT = 'zhihu2 (+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',
  'User-Agent':'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36',
  'authorization':'oauth c3cef7c66a1843f8b3a9e6a1e3160e20',
}

# Enable or disable spider middlewares
# See http://scrapy.readthedocs.org/en/latest/topics/spider-middleware.html
#SPIDER_MIDDLEWARES = {
#    'zhihu2.middlewares.Zhihu2SpiderMiddleware': 543,
#}

# Enable or disable downloader middlewares
# See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html
#DOWNLOADER_MIDDLEWARES = {
#    'zhihu2.middlewares.MyCustomDownloaderMiddleware': 543,
#}

# 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 = {
   'zhihu2.pipelines.MongoPipeline': 300,
}

# 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'