JSONDecoder 错误 - 使用 Python 访问 Google 翻译时 API

Question

I am learning to use HTTP requests in Python, using this HTTP request provided by a TopCoder training challenge (learning purposes only: no compensation of any sort) in which you have to access the Google Translate API:

curl --location --request POST 'https://translate.google.com/translate_a/single?client=at&dt=t&dt=ld&dt=qca&dt=rm&dt=bd&dj=1&hl=%25s&ie=UTF-8&oe=UTF-8&inputm=2&otf=2&iid=1dd3b944-fa62-4b55-b330-74909a99969e&' \
--header 'Content-Type: application/x-www-form-urlencoded' \
--header 'User-Agent: AndroidTranslate/5.3.0.RC02.130475354-53000263 5.1 phone TRANSLATE_OPM5_TEST_1' \
--data-urlencode 'sl=de' \
--data-urlencode 'tl=en' \
--data-urlencode 'q=Hallo' 

and I'm wondering how to make the equivalent request in my Python application? Any help is appreciated.

So far I have:

• installed and imported requests
• understood that I need to store my POST request in a variable and parse it with JSON.

The issue is that I get a JSONDecoder error

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Users\myname\Documents\Code\GoogleTranslateApiPy\env\lib\site-packages\requests\models.py", line 898, in json
    return complexjson.loads(self.text, **kwargs)
  File "c:\users\myname\appdata\local\programs\python\python38-32\lib\json\__init__.py", line 357, in loads
    return _default_decoder.decode(s)
  File "c:\users\myname\appdata\local\programs\python\python38-32\lib\json\decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "c:\users\myname\appdata\local\programs\python\python38-32\lib\json\decoder.py", line 355, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

with this Python request (I tried to translate the curl request as best as I could):

import requests

headers = {
    'Content-Type': 'application/x-www-form-urlencoded',
    'User-Agent': 'AndroidTranslate/5.3.0.RC02.130475354-53000263 5.1 phone TRANSLATE_OPM5_TEST_1',
}

params = (
    ('client', 'at'),
    ('dt', ['t', 'ld', 'qca', 'rm', 'bd']),
    ('dj', '1'),
    ('hl', '%s'),
    ('ie', 'UTF-8'),
    ('oe', 'UTF-8'),
    ('inputm', '2'),
    ('otf', '2'),
    ('iid', '1dd3b944-fa62-4b55-b330-74909a99969e'),
    ('', ''),
)

response = requests.get('https://translate.google.com/translate_a/single', headers=headers, params=params)

I feel that there's something fundamental I'm missing here. The request in the current documentation by Google for Translate differs from this provided request, but I'd like to know how I could get this way to work, in case I'm ever provided with a curl command like this in the future.

Answer 1

Two things:

1. You must do a POST request (currently you are doing a get request)

2. You are not including the body of the request. For example, the curl call includes url encoded data like this: data-urlencode 'q=Hallo'. You must include this parameters in your post request too, the provided link shows you how. This are key values that will go inside a dictionary, for example {q: 'Hallo', ...}

PS: I'm 90% sure that you should also convert to a dictionary the query params you currently have inside tuples. So, you'd have post with headers, params and data.