Integrating Google Apis with Rails (Missing token endpoint URI Error) - ruby-on-rails-4

Question

I want to use google apis in my app.
I successful get my access token but I am getting error :-
"Missing token endpoint URI."
My code is
def calender
client = Signet::OAuth2::Client.new(access_token: session[:access_token])
drive = Google::Apis::DriveV3::DriveService.new
drive.authorization = client
files = drive.list_files
end
when I printed my client variable, it showed my these details
#<Google::Apis::DriveV3::DriveService:0x0000010cc287f8
#root_url="https://www.googleapis.com/",
#base_path="drive/v3/",
#upload_path="upload/drive/v3/",
#batch_path="batch",
#client_options=#<struct Google::Apis::ClientOptions application_name="unknown", application_version="0.0.0", proxy_url=nil, use_net_http=false>,
#request_options=#<struct Google::Apis::RequestOptions
authorization=#<Signet::OAuth2::Client:0x0000010cc288c0
#authorization_uri=nil,
#token_credential_uri=nil,
#client_id=nil,
#client_secret=nil,
#code=nil,
#expires_at=nil,
#expires_in=nil,
#issued_at=nil,
#issuer=nil,
#password=nil,
#principal=nil,
#redirect_uri=nil,
#scope=nil,
#state=nil,
#username=nil,
#expiry=60,
#extension_parameters={},
#additional_parameters={},
#access_token="ya29.CjAbA8B7CFyhBLhFuEtP6kmCmuvJESwClkchiPpydjAqBOvDuvDERVCSVrYSSWLZvZc">, retries=0,
header=nil,
timeout_sec=nil,
open_timeout_sec=20>
I have spent two days to resolve this and explored whole internet but my issue is not resolved. My issue is related to already reported issue :-
Missing token endpoint URI while using a valid access_token
But solution provided in it is also not working for me. There is no attribute of "authentication" that I can use to assign my token.
I would greatly appreciate if someone help me with this.