FEATURE: Complete the community privacy

[mbeps]

Is your feature request related to a problem? Please describe.

Implement community privacy functionality:

• Prevent private communities from being accessible if the user is not subscribed
• Prevent users from posting on restricted communities if not subscribed

Describe the solution you'd like

• If the user tries to go to a private community, they would be told that the community is private and do not have access to it
• Private communities are not discoverable on the all communities page
• Users can navigate to restricted communities however they cannot post

Describe alternatives you've considered

Remove community privacy all together

Importance

• High
• Medium
• Low

[mbeps]

This feature seems simple to implement in principle but it's actually pretty difficult.

If the user tries to go to a private community, they would be told that the community is private and do not have access to it
Private communities are not discoverable on the all communities page
Users can navigate to restricted communities however they cannot post

These are easy to implement but how would a user gain access to a private community?
Are there checks for subscribing to restricted communities?

[mbeps]

Allowing the admin of a community seems to be a sensible choice until you realise that the community does not know what users are subscribed to it, but the users know what communities they are subscribed to. This means that the subscribers must be queried first which is a tedious task on a non-relational database. This is possible but not ideal due to the limitations of the database design.