測試通過時間：2019-8-20
參閱：C#實現谷歌翻譯API、Python之Google翻譯爬蟲
首先聲明，沒有什么不良動機，因為經常會用 translate.google.cn，就想着用 Python 模擬網頁提交實現文檔的批量翻譯。據說有 API，可是要收費。
生成 Token
Google 為防爬蟲而生成 token 的代碼是 Javascript 的，且是根據網站的 TKK 值和提交的文本動態生成。更新規律未知，只好定時去取一下了。
網上能找到的 Python 代碼大部分是去調用 PyExecJS 庫，先不說執行效率的高低（大概是差一個數量級），首先是舍近求遠，不純粹，本人不喜歡。
好不容易找到了一段 Python 代碼還有點小 Bug，且缺少動態獲取 TKK 的步驟。最后還是對照 Javascript 代碼自己改成 Python 了。方法很簡單，先轉成易懂的 Javascript，再轉成 Python。Javascript 代碼來自C#實現谷歌翻譯API。
原始（晦澀） Javascript 代碼
var b = function (a, b) {
for (var d = 0; d < b.length - 2; d += 3) {
var c = b.charAt(d + 2),
c = "a" <= c ? c.charCodeAt(0) - 87 : Number(c),
c = "+" == b.charAt(d + 1) ? a >>> c : a << c;
a = "+" == b.charAt(d) ? a + c & 4294967295 : a ^ c
}
return a
}
var tk = function (a,TKK) {
for (var e = TKK.split("."), h = Number(e[0]) || 0, g = [], d = 0, f = 0; f < a.length; f++) {
var c = a.charCodeAt(f);
128 > c ? g[d++] = c : (2048 > c ? g[d++] = c >> 6 | 192 : (55296 == (c & 64512) && f + 1 < a.length && 56320 == (a.charCodeAt(f + 1) & 64512) ? (c = 65536 + ((c & 1023) << 10) + (a.charCodeAt(++f) & 1023), g[d++] = c >> 18 | 240, g[d++] = c >> 12 & 63 | 128) : g[d++] = c >> 12 | 224, g[d++] = c >> 6 & 63 | 128), g[d++] = c & 63 | 128)
}
a = h;
for (d = 0; d < g.length; d++) a += g[d], a = b(a, "+-a^+6");
a = b(a, "+-3^+b+-f");
a ^= Number(e[1]) || 0;
0 > a && (a = (a & 2147483647) + 2147483648);
a %= 1E6;
return a.toString() + "." + (a ^ h)
}
易懂的 Javascript 代碼
function RL(a, b) {
for (var d = 0; d < b.length - 2; d += 3) {
var c = b.charAt(d + 2);
c = "a" <= c ? c.charCodeAt(0) - 87 : Number(c);
c = "+" == b.charAt(d + 1) ? a >>> c : a << c;
a = "+" == b.charAt(d) ? a + c & 4294967295 : a ^ c;
}
return a
}
function TL(a,TKK) {
var e = TKK.split(".");
var h = Number(e[0]) || 0;
var g = [];
var d = 0;
for (var f = 0; f < a.length; f++) {
var c = a.charCodeAt(f);
if (128 > c)
{
g[d++] = c;
}
else
{
if (2048 > c)
{
g[d++] = c >> 6 | 192;
}
else
{
if (55296 == (c & 64512) && f + 1 < a.length && 56320 == (a.charCodeAt(f + 1) & 64512))
{
c = 65536 + ((c & 1023) << 10) + (a.charCodeAt(++f) & 1023);
g[d++] = c >> 18 | 240;
g[d++] = c >> 12 & 63 | 128;
}
else
{
g[d++] = c >> 12 | 224;
g[d++] = c >> 6 & 63 | 128;
}
}
g[d++] = c & 63 | 128;
}
}
a = h;
for (var d = 0; d < g.length; d++) {
a += g[d];
a = b(a, "+-a^+6");
}
a = b(a, "+-3^+b+-f");
a ^= Number(e[1]) || 0;
0 > a && (a = (a & 2147483647) + 2147483648);
a %= 1E6;
return a.toString() + "." + (a ^ h)
}
Python 代碼
def getGoogleToken(a, TKK):
def RL(a, b):
for d in range(0, len(b)-2, 3):
c = b[d + 2]
c = ord(c[0]) - 87 if 'a' <= c else int(c)
c = a >> c if '+' == b[d + 1] else a << c
a = a + c & 4294967295 if '+' == b[d] else a ^ c
return a
g = []
f = 0
while f < len(a):
c = ord(a[f])
if 128 > c:
g.append(c)
else:
if 2048 > c:
g.append((c >> 6) | 192)
else:
if (55296 == (c & 64512)) and (f + 1 < len(a)) and (56320 == (ord(a[f+1]) & 64512)):
f += 1
c = 65536 + ((c & 1023) << 10) + (ord(a[f]) & 1023)
g.append((c >> 18) | 240)
g.append((c >> 12) & 63 | 128)
else:
g.append((c >> 12) | 224)
g.append((c >> 6) & 63 | 128)
g.append((c & 63) | 128)
f += 1
e = TKK.split('.')
h = int(e[0]) or 0
t = h
for item in g:
t += item
t = RL(t, '+-a^+6')
t = RL(t, '+-3^+b+-f')
t ^= int(e[1]) or 0
if 0 > t:
t = (t & 2147483647) + 2147483648
result = t % 1000000
return str(result) + '.' + str(result ^ h)
獲取 Token Key
Google 的 TKK 可以通過訪問網站 https://translate.google.cn 獲取，里面有段腳本里包含了“tkk:('xxxxxx.xxxxxx')”，用正則表達式截取即可。
res = requests.get('https://translate.google.cn', timeout = 3)
res.raise_for_status()
result = re.search(r'tkk\:\'(\d+\.\d+)?\'', res.text).group(1)
划分文章段落
因為常從 PDF 里復制文本翻譯，這樣就不能依賴換行符來划分段落了。只能判斷空行，作為段落的分界。
另外 Google 返回的結果 Json 里，會以英文句點作為分隔符，每一句譯文均作為數組的一項分開。所以最后得合並一下，成為一個段落。
完整代碼
代碼不長，全文黏貼如下。
GoogleTranslator.py：
import requests
import re
import json
import time
class GoogleTranslator ():
_host = 'translate.google.cn'
_headers = {
'Host': _host,
'User-Agent': 'Mozilla/5.0 (Linux; Android 6.0; Nexus 5 Build/MRA58N) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Mobile Safari/537.36',
'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
'Accept-Language': 'zh-CN,zh;q=0.8,en-US;q=0.5,en;q=0.3',
'Accept-Encoding': 'gzip, deflate, br',
'Content-Type': 'application/x-www-form-urlencoded;charset=utf-8',
'Referer': 'https://' + _host,
'Connection': 'keep-alive',
'Cache-Control': 'max-age=0'
}
_language = {
'afrikaans': 'af',
'arabic': 'ar',
'belarusian': 'be',
'bulgarian': 'bg',
'catalan': 'ca',
'czech': 'cs',
'welsh': 'cy',
'danish': 'da',
'german': 'de',
'greek': 'el',
'english': 'en',
'esperanto': 'eo',
'spanish': 'es',
'estonian': 'et',
'persian': 'fa',
'finnish': 'fi',
'french': 'fr',
'irish': 'ga',
'galician': 'gl',
'hindi': 'hi',
'croatian': 'hr',
'hungarian': 'hu',
'indonesian': 'id',
'icelandic': 'is',
'italian': 'it',
'hebrew': 'iw',
'japanese': 'ja',
'korean': 'ko',
'latin': 'la',
'lithuanian': 'lt',
'latvian': 'lv',
'macedonian': 'mk',
'malay': 'ms',
'maltese': 'mt',
'dutch': 'nl',
'norwegian': 'no',
'polish': 'pl',
'portuguese': 'pt',
'romanian': 'ro',
'russian': 'ru',
'slovak': 'sk',
'slovenian': 'sl',
'albanian': 'sq',
'serbian': 'sr',
'swedish': 'sv',
'swahili': 'sw',
'thai': 'th',
'filipino': 'tl',
'turkish': 'tr',
'ukrainian': 'uk',
'vietnamese': 'vi',
'yiddish': 'yi',
'chinese_simplified': 'zh-CN',
'chinese_traditional': 'zh-TW',
'auto': 'auto'
}
_url = 'https://' + _host + '/translate_a/single'
_params = {
'client': 'webapp',
'sl': 'en',
'tl': 'zh-CN',
'hl': 'zh-CN',
'dt': 'at',
'dt': 'bd',
'dt': 'ex',
'dt': 'ld',
'dt': 'md',
'dt': 'qca',
'dt': 'rw',
'dt': 'rm',
'dt': 'ss',
'dt': 't',
'otf': '1',
'ssel': '0',
'tsel': '0',
'kc': '1'
}
__cookies = None
__googleTokenKey = '376032.257956'
__googleTokenKeyUpdataTime = 600.0
__googleTokenKeyRetireTime = time.time() + 600.0
def __init__(self, src = 'en', dest = 'zh-CN', tkkUpdataTime = 600.0):
if src not in self._language and src not in self._language.values():
src = 'auto'
if dest not in self._language and dest not in self._language.values():
dest = 'auto'
self._params['sl'] = src
self._params['tl'] = dest
self.googleTokenKeyUpdataTime = tkkUpdataTime
self.__updateGoogleTokenKey()
def __updateGoogleTokenKey(self):
self.__googleTokenKey = self.__getGoogleTokenKey()
self.__googleTokenKeyRetireTime = time.time() + self.__googleTokenKeyUpdataTime
def __getGoogleTokenKey(self):
"""Get the Google TKK from https://translate.google.cn"""
# TKK example: '435075.3634891900'
result = ''
try:
res = requests.get('https://' + self._host, timeout = 3)
res.raise_for_status()
self.__cookies = res.cookies
result = re.search(r'tkk\:\'(\d+\.\d+)?\'', res.text).group(1)
except requests.exceptions.ReadTimeout as ex:
print('ERROR: ' + str(ex))
time.sleep(1)
return result
def __getGoogleToken(self, a, TKK):
"""Calculate Google tk from TKK """
# https://www.cnblogs.com/chicsky/p/7443830.html
# if text = 'Tablet Developer' and TKK = '435102.3120524463', then tk = '315066.159012'
def RL(a, b):
for d in range(0, len(b)-2, 3):
c = b[d + 2]
c = ord(c[0]) - 87 if 'a' <= c else int(c)
c = a >> c if '+' == b[d + 1] else a << c
a = a + c & 4294967295 if '+' == b[d] else a ^ c
return a
g = []
f = 0
while f < len(a):
c = ord(a[f])
if 128 > c:
g.append(c)
else:
if 2048 > c:
g.append((c >> 6) | 192)
else:
if (55296 == (c & 64512)) and (f + 1 < len(a)) and (56320 == (ord(a[f+1]) & 64512)):
f += 1
c = 65536 + ((c & 1023) << 10) + (ord(a[f]) & 1023)
g.append((c >> 18) | 240)
g.append((c >> 12) & 63 | 128)
else:
g.append((c >> 12) | 224)
g.append((c >> 6) & 63 | 128)
g.append((c & 63) | 128)
f += 1
e = TKK.split('.')
h = int(e[0]) or 0
t = h
for item in g:
t += item
t = RL(t, '+-a^+6')
t = RL(t, '+-3^+b+-f')
t ^= int(e[1]) or 0
if 0 > t:
t = (t & 2147483647) + 2147483648
result = t % 1000000
return str(result) + '.' + str(result ^ h)
def translate(self, text):
if time.time() > self.__googleTokenKeyRetireTime:
self.__updateGoogleTokenKey()
data = {'q': text}
self._params['tk'] = self.__getGoogleToken(text, self.__googleTokenKey)
result = ''
try:
res = requests.post(self._url,
headers = self._headers,
cookies = self.__cookies,
data = data,
params = self._params,
timeout = 6)
res.raise_for_status()
jsonText = res.text
if len(jsonText)>0:
jsonResult = json.loads(jsonText)
if len(jsonResult[0])>0:
for item in jsonResult[0]:
result += item[0]
return result
except Exception as ex:
print('ERROR: ' + str(ex))
return ''
import time
from GoogleTranslator import GoogleTranslator
def readFile(fileName):
with open(fileName, 'r') as f:
paragraph = ''
for line in f:
if line[0]!='\n':
paragraph += line.strip('\n')
else:
if len(paragraph)>0:
yield paragraph
paragraph = ''
if len(paragraph)>0:
yield paragraph
main.py：
def main():
translator = GoogleTranslator()
count = 0
with open('C:\\dx\\python\\d.txt', 'w', encoding='utf-8') as df:
for line in readFile('C:\\dx\\python\\s.txt'):
if len(line) > 1:
count += 1
print('\r' + str(count), end = '', flush = True)
df.write(line.strip() + "\n")
result = translator.translate(line)
df.write(result.strip() + "\n\n")
if __name__ == "__main__":
startTime = time.time()
main()
print()
print('%.2f seconds' % (time.time() - startTime))
結束語
求人不如求己。不能怕煩，代碼都是人敲出來的，找不到現成的還得靠自己編。
補充
高版本的word（至少2016可行）能直接打開PDF文件並自動轉換格式，多個換行能夠自動識別合並為段落。所以以上代碼可以自行修改簡化。