FEATURE: per-topic unsubscribe option in emails

[ShashankFC]

Test 2

Summary by CodeRabbit

Release Notes

• New Features
  • Users can now unsubscribe from topic notifications through a dedicated management page, allowing them to stop receiving notification alerts for specific topics.
  • Notification emails now include direct unsubscribe links, providing quick access to manage notification preferences.

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Replicated from ai-code-review-evaluation/discourse-coderabbit#2

[Copilot]

Pull request overview

This PR implements a per-topic unsubscribe feature that allows users to manage notification preferences for individual topics directly from email notifications.

Changes:

• Added new unsubscribe routes and controller action for topics
• Updated email templates to include topic-specific unsubscribe links
• Created JavaScript views, controllers, and routes for the unsubscribe UI
• Enhanced message builder to support custom unsubscribe URLs

Reviewed changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
config/routes.rb	Added topic unsubscribe routes with and without slug
app/controllers/topics_controller.rb	Implemented unsubscribe action to change notification levels
app/models/topic.rb	Added unsubscribe_url method
app/mailers/user_notifications.rb	Passed topic unsubscribe URL to email builder
lib/email/message_builder.rb	Formatting improvements for template args
config/locales/server.en.yml	Updated unsubscribe link text with topic-specific option
config/locales/client.en.yml	Added unsubscribe UI text
app/views/email/notification.html.erb	Code formatting improvements
app/assets/javascripts/discourse/routes/app-route-map.js.es6	Registered topicUnsubscribe route
app/assets/javascripts/discourse/routes/topic-unsubscribe.js.es6	Created route for unsubscribe page
app/assets/javascripts/discourse/controllers/topic-unsubscribe.js.es6	Created controller for unsubscribe page
app/assets/javascripts/discourse/views/topic-unsubscribe.js.es6	Created view for unsubscribe page
app/assets/javascripts/discourse/templates/topic/unsubscribe.hbs	Created template for unsubscribe page
app/assets/javascripts/discourse/components/dropdown-button.js.es6	Added title safety check
app/assets/stylesheets/common/base/topic.scss	Added styles for unsubscribe page
app/models/topic_user.rb	Code formatting improvements
app/assets/javascripts/discourse/routes/topic-from-params.js.es6	Modernized ES6 syntax
spec/components/email/message_builder_spec.rb	Updated test with unsubscribe_url parameter

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[Copilot]

Corrected spelling of 'stopNotificiations' to 'stopNotifications'.

Suggested change

	{{{stopNotificiationsText}}}
	{{{stopNotificationsText}}}

[Copilot]

Potential nil dereference if TopicUser record doesn't exist. The code accesses tu.notification_level without checking if tu is nil first. Add a nil check or handle the case where the user hasn't interacted with the topic yet.

Suggested change

	tu = TopicUser.find_by(user_id: current_user.id, topic_id: params[:topic_id])
	if tu.notification_level > TopicUser.notification_levels[:regular]
	tu.notification_level = TopicUser.notification_levels[:regular]
	else
	tu.notification_level = TopicUser.notification_levels[:muted]
	tu = TopicUser.find_or_initialize_by(user_id: current_user.id, topic_id: params[:topic_id])
	if tu.new_record?
	# User hasn't interacted with this topic yet; unsubscribe by muting it.
	tu.notification_level = TopicUser.notification_levels[:muted]
	else
	if tu.notification_level > TopicUser.notification_levels[:regular]
	tu.notification_level = TopicUser.notification_levels[:regular]
	else
	tu.notification_level = TopicUser.notification_levels[:muted]
	end

[Copilot]

Trailing comma missing after the last property definition. This is inconsistent with modern JavaScript best practices and can cause issues with certain tooling.