Python爬虫之JS逆向破解有道翻译

2019-08-17

一、使用Chrome进行分析

找到post请求地址：

原地址是：

1	url='http://fanyi.youdao.com/translate_o?smartresult=dict&smartresult=rule'

当经分析和查验，应使用如下地址：

1	url='http://fanyi.youdao.com/translate?smartresult=dict&smartresult=rule'

不然会报{“errorcode”:50}错误！

获取headers

headers={
          'Accept': 'application / json, text / javascript, * / *; q = 0.01',
          'Accept - Encoding': 'gzip, deflate',
          'Accept - Language': 'zh - CN, zh;q = 0.9',
          'Connection': 'keep - alive',
          'Content - Type': 'application / x - www - form - urlencoded;charset = UTF - 8',
          'Cookie': 'OUTFOX_SEARCH_USER_ID = 386503964 @ 10.108.160.18;JSESSIONID = aaaWewnrtmZEl - ulzptYw;OUTFOX_SEARCH_USER_ID_NCOO = 1961882954.448086;___rl__test__cookies = 1565847100747',
          'Host': 'fanyi.youdao.com',
          'Origin': 'http: // fanyi.youdao.com',
          'Referer': 'http: // fanyi.youdao.com /',
          'User - Agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36',
          'X - Requested - With': 'XMLHttpRequest'
  }

分析并获取data数据

data={
        'i': key,
        'from': 'AUTO',
        'to': 'AUTO',
        'smartresult': 'dict',
        'client': 'fanyideskweb',
        'salt': salt,
        'sign':sign_b(key,salt),
        'ts': salt[:-1],
        'bv': md5_b('Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36'),
        'doctype': 'json',
        'version': '2.1',
        'keyfrom': 'fanyi.web',
        'action': 'FY_BY_REALTlME'
    }

通过Chrome调试工具分析post所带的data应有如上几个key

其中salt，sign，ts，bv 是经过处理后得到的数据
经Chrome断点调试分析得到(调试方法：先找到post地址，然后根据sign这个字段在查询里面找到相应的js文件：fanyi.min.js)

二、附上源码：

import hashlib,time,random,requests
def md5_b(key):
    hash=hashlib.md5()
    hash.update(key.encode('utf-8'))
    return hash.hexdigest()
def sign_b(key,salt):
        sign='fanyideskweb'+key+str(salt)+'n%A-rKaT5fb[Gy?;N5@Tj'
        return md5_b(sign)
def translate(key):
    url='http://fanyi.youdao.com/translate?smartresult=dict&smartresult=rule'
    salt=str(int(time.time())*1000+random.randint(0,10))
    data={
        'i': key,
        'from': 'AUTO',
        'to': 'AUTO',
        'smartresult': 'dict',
        'client': 'fanyideskweb',
        'salt': salt,
        'sign':sign_b(key,salt),
        'ts': salt[:-1], #少了salt后面一位随机整数
        'bv': md5_b('Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36'),
        'doctype': 'json',
        'version': '2.1',
        'keyfrom': 'fanyi.web',
        'action': 'FY_BY_REALTlME'
    }
    headers={
            'Accept': 'application / json, text / javascript, * / *; q = 0.01',
            'Accept - Encoding': 'gzip, deflate',
            'Accept - Language': 'zh - CN, zh;q = 0.9',
            'Connection': 'keep - alive',
            'Content - Type': 'application / x - www - form - urlencoded;charset = UTF - 8',
            'Cookie': 'OUTFOX_SEARCH_USER_ID = 386503964 @ 10.108.160.18;JSESSIONID = aaaWewnrtmZEl - ulzptYw;OUTFOX_SEARCH_USER_ID_NCOO = 1961882954.448086;___rl__test__cookies = 1565847100747',
            'Host': 'fanyi.youdao.com',
            'Origin': 'http: // fanyi.youdao.com',
            'Referer': 'http: // fanyi.youdao.com /',
            'User - Agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36',
            'X - Requested - With': 'XMLHttpRequest'
    }
    res = requests.post(url, data=data, headers=headers).json()
    # print(res)

    result = res['translateResult'][0][0]
    result_tgt = result['tgt']
    result_src = result['src']

    print(f"""‘{result_src}’,翻译: ‘{result_tgt}’""")

    try:
        #  有时返回数据中会有其他翻译的，如果有的话，就打印出来。
        print('其它翻译:\n' + ''.join(res['smartResult']['entries']))
    except KeyError:
        pass

if __name__ == '__main__':
    translate('Hello world！')