import threading
from queue import Queue
from lxml import etree
import requests
import json
import time


class ThreadCrawl(threading.Thread):
    def __init__(self, threadName, pageQueue, dataQueue):
        # 调用父类的初始化方法
        # threading.Thread.__init__(self)
        super(ThreadCrawl, self).__init__()
        # 线程的名字
        self.threadName = threadName
        # 页码队列
        self.pageQueue = pageQueue
        # 数据队列
        self.dataQueue = dataQueue
        # 请求报头
        self.headers = {
            "Uaer-Agent": "Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_8; en-us) AppleWebKit/534.50 (KHTML, like Gecko) Version/5.1 Safari/534.50"
        }

    def run(self):
        print(‘启动:{}‘.format(self.threadName))
        while not CRAWL_EXIT:
            try:
                # 取出队列中的一个数字, 先进先出
                # 可选参数block, 默认值为True, 两种用法
                # 1. 如果队列为空, block为True的话, 不会结束, 就会进入阻塞状态, 知道队列有新的数据
                # 2. 如果队列为空, block为False的话, 就会弹出一个Queue.empty()异常
                page = self.pageQueue.get(False)
                url = ‘http://www.qiushibaike.com/8hr/page/{}/‘.format(page)
                content = requests.get(url, headers=self.headers).text
                # content = content.decode(‘utf-8‘)
                # print(content)
                time.sleep(1)
                self.dataQueue.put(content)
            except:
                pass
        print(‘结束:{}‘.format(self.threadName))


class ThreadParse(threading.Thread):
    def __init__(self, threadName, dataQueue, filename, lock):
        super(ThreadParse, self).__init__()
        # 线程的名字
        self.threadName = threadName
        # 数据队列
        self.dataQueue = dataQueue
        # 保存解析后数据的文件名
        self.filename = filename
        # 锁
        self.lock = lock

    def run(self):
        print(‘启动:{}‘.format(self.threadName))
        while not PARSE_EXIT:
            try:
                html = self.dataQueue.get(False)
                self.parse(html)
            except:
                pass
        print(‘结束:{}‘.format(self.threadName))

    def parse(self, html):
        # 解析为HTML DOM
        html = etree.HTML(html)
        node_list = html.xpath(‘//div[contains(@class, "article block untagged mb15")]‘)
        for node in node_list:
            # print(node)
            # xpath返回的列表，这个列表就这一个参数，用索引方式取出来，用户名
            # .//h2  用户名
            username = node.xpath(‘.//h2‘)[0].text.strip()
            # print(‘username==={}‘.format(username))
            # .//div[@class="thumb"]//@src  图片连接
            image = node.xpath(‘.//div[@class="thumb"]//@src‘)
            # print(‘image==={}‘.format(image))
            # .//div[@class="content"]/span    取出标签下的内容,段子内容
            content = node.xpath(‘.//div[@class="content"]/span‘)[0].text.strip()
            # print(‘content==={}‘.format(content))
            # .//i[@class="number"][0] 点赞  取出标签里包含的内容，点赞
            zan = node.xpath(‘.//i[@class="number"]‘)[0].text
            # print(‘zan==={}‘.format(zan))
            # .//i[@class="number"][i] 评论
            comments = node.xpath(‘.//i[@class="number"]‘)[1].text
            # print(‘comments==={}‘.format(comments))
            items = {
                "username" : username,
                "image" : image,
                "content" : content,
                "zan" : zan,
                "comments" : comments
            }

            # with 后面有两个必须执行的操作：__enter__ 和 _exit__
            # 不管里面的操作结果如何，都会执行打开、关闭
            # 打开锁、处理内容、释放锁
            # print("正在写入内容!!!")
            with self.lock:
                # print("正在写入内容!!!")
                # # 写入存储的解析后的数据
                # json_data = json.dumps(items, ensure_ascii=False)
                # print(‘jsondata==={}‘.format(json_data))
                # self.filename.write(json_data.encode("utf-8") + "\n")
                self.filename.write(str(json.dumps(items, ensure_ascii = False))+‘\n‘)
                print("写入完成!!!")


# 采集爬虫退出信号
CRAWL_EXIT = False
# 解析爬虫退出信号
PARSE_EXIT = False


def main():
    # 页码的队列, 表示10个页面
    pageQueue = Queue(10)
    # 放入1~10个数字, 先进先出
    for i in range(1, 11):
        pageQueue.put(i)

    # 采集结果(每页的html源码)的数据队列, 参数为空表示不限制
    dataQueue = Queue()

    filename = open(‘duanzi.json‘, ‘a‘, encoding=‘utf-8‘)
    print("打开文件!!!")

    # 创建锁
    lock = threading.Lock()

    # 三个采集线程的名字
    crawlList = ["采集线程1号", "采集线程2号", "采集线程3号"]

    # 存储三个采集线程的列表集合
    threadcrawl = []

    for threadName in crawlList:
        thread = ThreadCrawl(threadName, pageQueue, dataQueue)
        thread.start()
        threadcrawl.append(thread)
        time.sleep(1)

    # 三个解析线程的名字
    parseList = ["解析线程1号", "解析线程2号", "解析线程3号"]

    # 存储三个解析线程
    threadparse = []

    for threadName in parseList:
        thread = ThreadParse(threadName, dataQueue, filename, lock)
        thread.start()
        threadparse.append(thread)

    # 等待pageQueue队列为空, 等待之前的操作执行完毕
    while not pageQueue.empty():
        pass

    # 如果pageQueue为空, 采集线程退出循环
    global CRAWL_EXIT
    CRAWL_EXIT = True

    print(‘pageQueue队列为空‘)

    for thread in threadcrawl:
        thread.join()
        print("1")

    while not dataQueue.empty():
        pass

    global PARSE_EXIT
    PARSE_EXIT = True

    for thread in threadparse:
        thread.join()
        print("2")

    with lock:
        print("关闭文件!!!")
        # 关闭文件
        filename.close()
    print("谢谢使用")


if __name__ == ‘__main__‘:
    main()