This Spigot plugin works with DiscordSRV to allow login only for users with specific roles who have joined the Discord server.
Not well tested and may cause problems.
Please submit issues and fixes to github issues and pull requests.
DiscordSRV is required as a dependency.

Installation
Add DiscordSRV and AllowMcMember to the plugins folder.
Start once and edit the items in the generated "plugin/AllowMcMember/config.yml". The contents are as follows:

• KickMessage
  Message when a user in an unauthorized role joins
• linkMessage
  Message when a user who is not linked to the Discord account joins
• AllowUser
  Discord role ID of the user to be allowed
• RestrictionDay
  Days of the week to be restricted, deleted days of the week are not subject to restrictions and all users can participate
• Hours
  Date switch time (hour)
• Minutes
  Date switch time (minutes)