I have a social media app written in Flutter. Users can see the profiles each other and block/unblock them. I'm using MySQL to keep that data. Now I want to implement chat feature using Firebase Firestore (or maybe MongoDB). When a user sends a message to another user, should I check if user blocked another user from MySQL every time, so user can't send new message. Is this a good practice in chat application, or should I store the "blocked" data at Firebase also.

I researched this subject deeply but didn't find any solution.

CodePudding user response：

So you can code like most of the current social media works.

Simply let the user send a message but put a condition on the receiver user side so if the user is blocked by the receiver then it should not show the chat in the user chat list also should not send a notification if the user is blocked by the receiver.

CodePudding user response：

Like when user is trying to send a message to another user so in the list of the recipients you are also retrieving the value for (is particular user is blocked by the current user), if it's so you are checking this on that time.

Secondly, if you want this to check when sending to server. So, you can manage this using firestore transaction in which you might get the object of the sender and check to whom the sender has blocked and you may throw an exception. The other thing you might manage it using Firestore Security Rules as well.