I am trying to use this assertion to create an ID token as JSON message but having some difficulties.
I was able to figure out most of the fields except these:
sub - This is not super important for me
exp - This is what causing me pain. Document says "Enter the expiration date in seconds since 01.01.1970-00:00:00"
This is epoch format. How do I set this field with an expiration time of 15 mins for each token generated but at diff times?
There is no OAuth so the optional stuff doesn't apply for this use case.