"error" : "invalid_grant" for server to sever application

[David Ou]

Dear,

 

Our website need daily check customer purchase, so I need to use oauth 2.0 for sever to server application.

I try use example as https://developers.google.com/accounts/docs/OAuth2ServiceAccount

 

POST /o/oauth2/token HTTP/1.1
Host: accounts.google.com
Content-Type: application/x-www-form-urlencoded

grant_type=assertion&assertion_type=http%3A%2F%2Foauth.net%2Fgrant_type%2Fjwt%2F1.0%2Fbearer&assertion=eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiI3NjEzMjY3OTgwNjktcjVtbGpsbG4xcmQ0bHJiaGc3NWVmZ2lncDM2bTc4ajVAZGV2ZWxvcGVyLmdzZXJ2aWNlYWNjb3VudC5jb20iLCJzY29wZSI6Imh0dHBzOi8vd3d3Lmdvb2dsZWFwaXMuY29tL2F1dGgvcHJlZGljdGlvbiIsImF1ZCI6Imh0dHBzOi8vYWNjb3VudHMuZ29vZ2xlLmNvbS9vL29hdXRoMi90b2tlbiIsImV4cCI6MTMyODU3MzM4MSwiaWF0IjoxMzI4NTY5NzgxfQ.ixOUGehweEVX_UKXv5BbbwVEdcz6AYS-6uQV6fGorGKrHf3LIJnyREw9evE-gs2bmMaQI5_UbabvI4k-mQE4kBqtmSpTzxYBL1TCd7Kv5nTZoUC1CmwmWCFqT9RE6D7XSgPUh_jF1qskLa2w0rxMSjwruNKbysgRNctZPln7cqQ

 

I got   "error" : "invalid_grant" message and I try my private key as

POST /o/oauth2/token HTTP/1.1
Content-Type: application/x-www-form-urlencoded
Host: accounts.google.com

grant_type=assertion&assertion_type=http%3A%2F%2Foauth.net%2Fgrant_type%2Fjwt%2F1.0%2Fbearer&assertion=eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiI3NTM1NTMyMzcxNTMtYWJ2Y3VlN2xlZGw4NDg5NTA4cDB2MHM0M3J1OGprNXBAZGV2ZWxvcGVyLmdzZXJ2aWNlYWNjb3VudC5jb20iLCJzY29wZSI6Imh0dHBzOi8vd3d3Lmdvb2dsZWFwaXMuY29tL2F1dGgvZ2FuLnJlYWRvbmx5IiwiYXVkIjoiaHR0cHM6Ly9hY2NvdW50cy5nb29nbGUuY29tL28vb2F1dGgyL3Rva2VuIiwiZXhwIjoxMzQyMTc5MzAwLCJpYXQiOjEzNDIxNzYwMDB9.YzVLjjgvohsFdRoT7TuafF9XtC81b_G58mdra4s-ho8

I got the same error Message "error" : "invalid_grant"

Does anyone help me to solve problem?

Best Regards,

David Ou