How to generate authorization token in R?

Dear community,

I'm trying to generate an authorization token to Power BI Service in R. Thanks to Tom Martens there is his experience mentioned in this topic - https://community.powerbi.com/t5/Service/connect-to-Power-BI-Service-using-R/m-p/119697#M18632

When I tried, it was unsuccessful. Can somebody help to find out what is wrong in below R script?

library("httr");
library("httpuv")

# 
#oauth_endpoints("azure")
powerbi.urls <- oauth_endpoint(  
  "authorize",  
  "token",
  base_url = "https://login.windows.net/common/oauth2")

powerbi.app <- oauth_app(
  "myAppName",
  key="my_client_id-value", 
  secret="my_secret_id-value"
)

powerbi.token <- oauth2.0_token(powerbi.urls, powerbi.app,
                                user_params = list(resource = "https://analysis.windows.net/powerbi/api"),
                                use_oob = FALSE)

Regards,

Ruslan