结合acts_as_follower与activity_notification无法接收通知的问题排查

Hey there! Let's break down what's going wrong with your notification setup and get it working properly.

First, let's look at the core issue in your original acts_as_notifiable configuration. Your Follow model doesn't have a direct user attribute—instead, it uses polymorphic associations for follower (the user doing the following) and followable (the user being followed). That's why your initial targets lambda isn't working: follow.user doesn't exist!

Your proposed rewrite also won't work because current_user.follow isn't a valid association, and the lambda parameters for acts_as_notifiable are (notifiable, key) (not current_user, key). The notifiable here is the Follow instance being created.

Step 1: Correct the Follow Model Configuration #

Let's fix the acts_as_notifiable setup to target the right user (the one being followed). Here's the corrected code:

class Follow < ActiveRecord::Base
  extend ActsAsFollower::FollowerLib
  extend ActsAsFollower::FollowScopes

  belongs_to :followable, polymorphic: true
  belongs_to :follower, polymorphic: true

  def block!
    self.update_attribute(:blocked, true)
  end

  acts_as_notifiable :users,
    # Target the user being followed (follow.followable is the User instance)
    targets: ->(follow, _key) { [follow.followable].compact },
    tracked: true,
    # Optional: Set the path users land on when clicking the notification
    notifiable_path: ->(follow, target_user) { user_path(follow.follower) }
end

• targets: ->(follow, _key) { [follow.followable].compact }: This ensures the notification is sent to the user being followed (since that's who would want to know someone followed them). The .compact handles any edge cases where followable might be nil.
• notifiable_path: This adds a custom link to the notification (taking the target user to the follower's profile). You can adjust this to whatever makes sense for your app.

Step 2: Ensure Your User Model is Configured as a Notification Target #

You need to tell activity_notification that your User model is a valid recipient for notifications. Add this to your User model:

class User < ApplicationRecord
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :validatable

  # Required for acts_as_follower functionality
  acts_as_follower
  acts_as_followable

  # Required for activity_notification to send notifications to users
  acts_as_notification_target
end

Step 3: Verify Database Setup #

Make sure you've run the activity_notification installation and migrations. If you haven't, run these commands:

rails generate activity_notification:install
rails db:migrate

This creates the necessary tables (like notifications) to store notification data.

Step 4: Test the Flow #

When a user follows another user (e.g., current_user.follow(other_user)), a Follow record is created. With tracked: true in your Follow model, activity_notification should automatically generate a notification for other_user.

You can check if notifications are being created by running this in your Rails console:

Notification.last

If it exists and has the correct target (the user being followed), your setup is working.

Common Pitfalls to Check #

• Polymorphic Association Types: Ensure that when you call current_user.follow(other_user), the followable_type in the follows table is set to "User" (no typos!).
• Devise Current User: Double-check that your controllers have access to current_user (Devise should handle this out of the box, but custom controllers might need extra setup).

内容的提问来源于stack exchange，提问作者Fernando Aureliano