用过很多网页在线翻译,我发现谷歌翻译还是很专业的,最近也学习了python的爬虫,于是就有了利用爬虫实现谷歌翻译的想法。
首先,打开谷歌翻译的网址:https://translate.google.cn/
按下F12,查看Network,发现请求的url:https://translate.google.cn/translate_a/single?client=webapp&sl=auto&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&tk=247702.353673&q=%E6%88%91%E6%98%AF已经包含了很多信息,可以看到sl=auto&tl=zh-CN&hl=zh-CN这几个是翻译语言的选择;请求方式为get,还是很好爬取的。
再往下看,最后的Query String Parameters包含的信息和请求的URL中一样,很容易理解到这里就是请求数据,q的数据项就是我们输入的待翻译文本
这里还有一项数据tk,刚开始我直接复制粘贴这一数据,发现翻译其他的文本时并不可行,于是知道了这时网页通过js产生的随机数字,而且和输入的文本有关。为此,我们需要获取谷歌翻译的js文件。其中一段关于tk的代码如下:
function TL(a) { var k = ""; var b = 406644; var b1 = 3293161072; var jd = "."; var $b = "+-a^+6"; var Zb = "+-3^+b+-f"; for (var e = [], f = 0, g = 0; g < a.length; g++) { var m = a.charCodeAt(g); 128 > m ? e[f++] = m : (2048 > m ? e[f++] = m >> 6 | 192 : (55296 == (m & 64512) && g + 1 < a.length && 56320 == (a.charCodeAt(g + 1) & 64512) ? (m = 65536 + ((m & 1023) << 10) + (a.charCodeAt(++g) & 1023), e[f++] = m >> 18 | 240, e[f++] = m >> 12 & 63 | 128) : e[f++] = m >> 12 | 224, e[f++] = m >> 6 & 63 | 128), e[f++] = m & 63 | 128) } a = b; for (f = 0; f < e.length; f++) a += e[f], a = RL(a, $b); a = RL(a, Zb); a ^= b1 || 0; 0 > a && (a = (a & 2147483647) + 2147483648); a %= 1E6; return a.toString() + jd + (a ^ b) }; function RL(a, b) { var t = "a"; var Yb = "+"; for (var c = 0; c < b.length - 2; c += 3) { var d = b.charAt(c + 2), d = d >= t ? d.charCodeAt(0) - 87 : Number(d), d = b.charAt(c + 1) == Yb ? a >>> d: a << d; a = b.charAt(c) == Yb ? a + d & 4294967295 : a ^ d } return a }
还是比较复杂的,我们通过python中的execjs模块来编译这部分代码,命名为HandleJs.py:
import execjs class Py4Js(): def __init__(self): self.ctx = execjs.compile(""" function TL(a) { var k = ""; var b = 406644; var b1 = 3293161072; var jd = "."; var $b = "+-a^+6"; var Zb = "+-3^+b+-f"; for (var e = [], f = 0, g = 0; g < a.length; g++) { var m = a.charCodeAt(g); 128 > m ? e[f++] = m : (2048 > m ? e[f++] = m >> 6 | 192 : (55296 == (m & 64512) && g + 1 < a.length && 56320 == (a.charCodeAt(g + 1) & 64512) ? (m = 65536 + ((m & 1023) << 10) + (a.charCodeAt(++g) & 1023), e[f++] = m >> 18 | 240, e[f++] = m >> 12 & 63 | 128) : e[f++] = m >> 12 | 224, e[f++] = m >> 6 & 63 | 128), e[f++] = m & 63 | 128) } a = b; for (f = 0; f < e.length; f++) a += e[f], a = RL(a, $b); a = RL(a, Zb); a ^= b1 || 0; 0 > a && (a = (a & 2147483647) + 2147483648); a %= 1E6; return a.toString() + jd + (a ^ b) }; function RL(a, b) { var t = "a"; var Yb = "+"; for (var c = 0; c < b.length - 2; c += 3) { var d = b.charAt(c + 2), d = d >= t ? d.charCodeAt(0) - 87 : Number(d), d = b.charAt(c + 1) == Yb ? a >>> d: a << d; a = b.charAt(c) == Yb ? a + d & 4294967295 : a ^ d } return a } """) def getTk(self,text): return self.ctx.call("TL",text)
然后新建Translator-google.py,导入自己编写的库:
import requests from HandleJs import Py4Js def translate(lan_From,lan_To,tk, text): param = {'tk': tk, 'q': text} r = requests.get('http://translate.google.cn/translate_a/single?client=t&sl=auto&tl='+lan_To+'&hl='+lan_From+'&dt=at&dt=bd&dt=ex&dt=ld&dt=md&dt=qca&dt=rw&dt=rm&dt=ss&dt=t&ie=UTF-8&oe=UTF-8&clearbtn=1&otf=1&pc=1&srcrom=0&ssel=0&tsel=0&kc=1', params=param) text=r.json() result=text[0][0][0] #返回的时关于翻译文本和翻译语种的列表 print(result) if __name__ == "__main__": lan_From=input('Please enter which language you want to translate from(default:auto):') lan_To = input('Please enter which language you want to translate to:') text=input('Please enter your words for translating:') js = Py4Js() tk = js.getTk(text) translate(lan_From,lan_To,tk,text)
运行结果如下:
这里选择不同翻译语言需要输入谷歌翻译内置的语言缩写,如中文是zh-CN,日文是ja,英文是en等。
后续会添加图形界面,实现真正的人机交互。