我正在使用谷歌提供的OAuth游乐场。虽然我的调用中有grant_type参数，但它无法识别它。为了继续调用API，我需要刷新令牌;然而，即使在操场上，电话也无法正常工作。
POST /o/oauth2/token?client_id=##########.apps.googleusercontent.com&client_secret=##########&refresh_token=##########-###########&grant_type=refresh_token
HTTP/1.1
Host: accounts.google.com
Content-length: 0
Content-type: application/json
Authorization: Bearer ya29.1.AADtN_WMOMyvBKs_HomU60xaG1kJM2hUKFz1i7oVbCnGI-Bouk9VEqMDFJ1VbFA
HTTP/1.1 400 Bad Request
Alternate-protocol: 443:quic
Content-length: 102
X-xss-protection: 1; mode=block
X-content-type-options: nosniff
Content-disposition: attachment; filename="json.txt"; filename*=UTF-8''json.txt
Expires: Fri, 01 Jan 1990 00:00:00 GMT
X-google-cache-control: remote-fetch
Server: GSE
Via: HTTP/1.1 GWA
Pragma: no-cache
Cache-control: no-cache, no-store, max-age=0, must-revalidate
Date: Thu, 24 Apr 2014 19:16:45 GMT
X-frame-options: SAMEORIGIN
Content-type: application/json; charset=utf-8
-content-encoding: gzip
{
"error_description": "Required parameter is missing: grant_type",
"error": "invalid_request"
}