蜗牛之路

一、代码

二、出错
可是下载了一百多篇论文就报错了，原来出现了验证码。可是我设定为自动识别验证码了，还是报以下的错误。

ERROR:root:出现验证码
Traceback (most recent call last):
File "main.py", line 144, in parse_page
tr_table.tr.extract()
AttributeError: 'NoneType' object has no attribute 'tr'

原来采集了10多页的时候，会跳出验证码的页面：

通过查看源码，发现验证码图片的地址为：
https://kns.cnki.net/kns/checkcode.aspx?t=%270.0684436452893744

需要构建参数：

rurl:/kns/brief/brief.aspx?curpage=17&RecordsPerPage=20&QueryID=1&ID=&turnpage=1&tpagemode=L&dbPrefix=SCDB&Fields=&DisplayMode=listmode&PageName=ASP.brief_result_aspx&isinEn=1&
vericode:"RLVB4"

三、云打码
http://www.yundama.com

使用非常方便

不过注册默认是没有积分的，我开始注册了普通用户，可是无法取得appkey，appid，后来又注册了一个开发者账户，发现开发者账户又无法充值，我联系在线客服QQ，无人应答，然后打网站上留的手机号码，结果关机。反正这个网站设计得有点脑残。后来我在普通用户那里充值，然后使用开发者账户的appkey，appid，终于识别成功了。

充值了一元，得到2000分，识别一个码要花费10分。

代码

import http.client, mimetypes, urllib, json, time, requests

######################################################################

class YDMHttp:

    apiurl = 'http://api.yundama.com/api.php'
    username = ''
    password = ''
    appid = ''
    appkey = ''

    def __init__(self, username, password, appid, appkey):
        self.username = username  
        self.password = password
        self.appid = str(appid)
        self.appkey = appkey

    def request(self, fields, files=[]):
        response = self.post_url(self.apiurl, fields, files)
        response = json.loads(response)
        return response
    
    def balance(self):
        data = {'method': 'balance', 'username': self.username, 'password': self.password, 'appid': self.appid, 'appkey': self.appkey}
        response = self.request(data)
        if (response):
            if (response['ret'] and response['ret'] < 0):
                return response['ret']
            else:
                return response['balance']
        else:
            return -9001
    
    def login(self):
        data = {'method': 'login', 'username': self.username, 'password': self.password, 'appid': self.appid, 'appkey': self.appkey}
        response = self.request(data)
        if (response):
            if (response['ret'] and response['ret'] < 0):
                return response['ret']
            else:
                return response['uid']
        else:
            return -9001

    def upload(self, filename, codetype, timeout):
        data = {'method': 'upload', 'username': self.username, 'password': self.password, 'appid': self.appid, 'appkey': self.appkey, 'codetype': str(codetype), 'timeout': str(timeout)}
        file = {'file': filename}
        response = self.request(data, file)
        if (response):
            if (response['ret'] and response['ret'] < 0):
                return response['ret']
            else:
                return response['cid']
        else:
            return -9001

    def result(self, cid):
        data = {'method': 'result', 'username': self.username, 'password': self.password, 'appid': self.appid, 'appkey': self.appkey, 'cid': str(cid)}
        response = self.request(data)
        return response and response['text'] or ''

    def decode(self, filename, codetype, timeout):
        cid = self.upload(filename, codetype, timeout)
        if (cid > 0):
            for i in range(0, timeout):
                result = self.result(cid)
                if (result != ''):
                    return cid, result
                else:
                    time.sleep(1)
            return -3003, ''
        else:
            return cid, ''

    def report(self, cid):
        data = {'method': 'report', 'username': self.username, 'password': self.password, 'appid': self.appid, 'appkey': self.appkey, 'cid': str(cid), 'flag': '0'}
        response = self.request(data)
        if (response):
            return response['ret']
        else:
            return -9001

    def post_url(self, url, fields, files=[]):
        for key in files:
            files[key] = open(files[key], 'rb');
        res = requests.post(url, files=files, data=fields)
        return res.text

######################################################################

# 用户名
username    = 'd8'

# 密码
password    = 'k4'                            

# 软件ＩＤ，开发者分成必要参数。登录开发者后台【我的软件】获得！
appid       = 10405                                    

# 软件密钥，开发者分成必要参数。登录开发者后台【我的软件】获得！
appkey      = '643aa'    

# 图片文件
filename    = '33.gif'                        

# 验证码类型，# 例：1004表示4位字母数字，不同类型收费不同。请准确填写，否则影响识别率。在此查询所有类型 http://www.yundama.com/price.html
codetype    = 1005

# 超时时间，秒
timeout     = 60                                    

# 检查
if (username == 'username'):
    print('请设置好相关参数再测试')
else:
    # 初始化
    yundama = YDMHttp(username, password, appid, appkey)

    # 登陆云打码
    uid = yundama.login();
    print('uid: %s' % uid)

    # 查询余额
    balance = yundama.balance();
    print('balance: %s' % balance)

    # 开始识别，图片路径，验证码类型ID，超时时间（秒），识别结果
    cid, result = yundama.decode(filename, codetype, timeout);
    print('cid: %s, result: %s' % (cid, result))

######################################################################

参考：https://www.bilibili.com/video/BV1Vb411F7yG?from=search&seid=292596025331943924