a) Log into Amazon Developer Console
https://developer.amazon.com/dashboard
b) Login with Amazon > Create a Security Profile
c) Generate client id and client secret.
d) Add redirect url under web settings as a whitelist redirect url.
e) Generate Authorization Code (One Time)
https://www.amazon.com/ap/oa?client_id=xxxxxxxxxxx&response_type=code&redirect_uri=http://localhost&scope=profile&state=SPECIAL
f) Generate Refresh Token (One Time)
curl --request POST --data "code=xxxxxxxxxxx&client_id=xxxxxxxxxxxx&client_secret=xxxxxxxxxxxxx&redirect_uri=http://localhost&grant_type=authorization_code" https://api.amazon.com/auth/o2/token
g) Generate Access Token from Refresh token (Always)
curl --request POST --data "client_id=xxxxxxxxxxx&client_secret=xxxxxxxxxxx&refresh_token=xxxxxxxxxxxxxxxxxxx&grant_type=refresh_token" https://api.amazon.com/auth/o2/token
