This is a simple microservice that can create users, issue jwt tokens and validate them

• CONNECTION_STRING some postgres connection string. Format: postgres://user:password@host:port/database_name
• SECRET the hmac sh256 signing secret
• ISSUER the issuer name on the tokens
• AUDIENCE optional: the audience on the tokens
• EXPIRY_TIME optional: the time after which a JWT expires. This is parsed with Zeit/ms.
• PORT optional: in docker this is set to 80 by default
• ADMIN_USER optional: set this to set the user id for the admin user. Default: admin
• ADMIN_PASS: optional: set this to set the password for the admin user. If you don't set this then no admin user is created.

Setting ADMIN_PASS essentially only needs to happen once on first run, since the admin user doesn't need to be recreated every time. It is safe to keep it set though. If a user with ADMIN_USER as username already exists, it won't be modified and admin user creation will be skipped.