selenium+phantomjs模拟登录京东后台并且保存cookies

做爬虫的同学应该经常遇到登录验证的问题，在这里我使用phantomejs模拟登录并且保存cookies，方便再次登录。废话不多说，直接切入正题。

• 模拟登录

def login(username, password, driver=None):
    url = 'https://www.jd.com/productDetail.html'
    driver.get(url)
    driver.find_element_by_xpath('//input[@id="loginname"]').send_keys(username)
    logger.info ('已输入账号')
    driver.find_element_by_xpath('//input[@id="nloginpwd"]').send_keys(password)
    logger.info ('已输入密码')
    driver.find_element_by_xpath('//a[@id="loginsubmit"]').click()
    logger.info ('已点击登录按钮')
    return driver

• 从网上获取cookies

    def get_cookies_from_network():
        driver = login(username, password, driver)
        # 获取cookies保存到本地并且返回此cookies
        cookies = driver.get_cookies()
        cookie_dict = {}
        logger.info(cookies)
        for cookie in cookies:
            if 'name' in cookie.keys() and 'value' in cookie.keys():
                cookie_dict[cookie['name']] = cookie['value']
        logger.info(cookie_dict)
        with open('cookies.txt', 'w') as f:
            # 保存cookies到本地
            f.write(json.dumps(cookies))
            logger.info("保存cookis成功.")
        return cookie_dict

• 从本地缓存获取cookies

    def get_cookies_from_cache():
        cookies_dict = {}
        if os.path.exists('cookies.txt'):
            # 如果本地有cookies文件，则读取本地cookies，否则返回空
            with open('cookies.txt', 'r') as f:
                for i in json.loads(f.read()):
                    if 'name' in i.keys() and 'value' in i.keys():
                        if 'expiry' in i.keys():
                            expiry_date = int(i['expiry'])
                            # 判断cookies是否过期，过期则返回空
                            if expiry_date > (int)(time.time()):
                                cookies_dict[i['name']] = i['value']
                            else:
                                logger.info('过期啦：{}'.format(i['name']))
                                return {}
                        else:
                            cookies_dict[i['name']] = i['value']
        else:
            return cookies_dict
        logger.info(cookies_dict)
        return cookies_dict

• 获取cookies时，优先访问本地的cookies，如果cookies过期则再次获取。

    def get_cookies():
        # 先从本地获取cookies
        cookie_dict = get_cookies_from_cache()
        if not cookie_dict:
            # 从本地返回的cookies为空则从网上获取cookies
            cookie_dict = self.get_cookies_from_network()
        return cookie_dict

• 带着cookies登录网站

    def get_content(driver=None):
        #获取cookies
        cookies = get_cookies()
        # 先访问一遍目标网站
        driver.get(url)
        # 删除当前的cookies
        driver.delete_all_cookies()
        for k,v in cookies.items():
            # 添加cookies
            driver.add_cookie({'name': k, 'value': v})
        time.sleep(1)
        logger.info('get url again')
        # 再次访问目标网站，模拟登录成功
        driver.get(self.url)
        logger.info(driver.page_source)

之后在cookies过期前可以以登录状态访问网页