MongoID many to many relation ship

Question

I have two models with following relations,

Class User
has_and_belongs_to_many :notification_channels

Class NotificationChannel
has_and_belongs_to_many :users

I am able to add notification channel for a user object in this way

@user.notification_channels << @notification

But removing channel from user's channels will remove the channel document from channels collection with following query

@user.notification_channels.find_by(id: params[:channel_id]).destroy 

how can I remove a channel from user's channel ?

Answer 1

Here is the solution

 @user.notification_channels -= [NotificationChannel.find_by(id: params[:channel_id])] # relationship is removed both ways and both objects are saved

OR

 @user.notification_channels.delete(NotificationChannel.find_by(id: params[:channel_id])) # relationship is removed both ways but @user needs to be saved manually
 @user.save

Will do the trick.