Followers-only post federation (#2111)

* Make private toots get PuSHed to subscription URLs that belong to domains where you have approved followers

* Authorized followers controller, stub for bulk action

* Soft block in the background

* Add simple test for new controller

* Rename Settings::FollowersController to Settings::FollowerDomainsController, paginate results,
rename "private" post setting to "followers-only", fix pagination style, improve post privacy
preferences style, improve warning style

* Extract compose form warnings into own container, show warning when posting to followers-only with unlocked account

app/workers/import_worker.rb

@@ -4,6 +4,7 @@ require 'csv'
 
 class ImportWorker
   include Sidekiq::Worker
+
   sidekiq_options queue: 'pull', retry: false
 
   attr_reader :import

app/workers/pubsubhubbub/distribution_worker.rb

@@ -8,12 +8,14 @@ class Pubsubhubbub::DistributionWorker
   def perform(stream_entry_id)
     stream_entry = StreamEntry.find(stream_entry_id)
 
-    return if stream_entry.hidden?
+    return if stream_entry.status&.direct_visibility?
 
     account = stream_entry.account
     payload = AtomSerializer.render(AtomSerializer.new.feed(account, [stream_entry]))
+    domains = account.followers_domains
 
     Subscription.where(account: account).active.select('id, callback_url').find_each do |subscription|
+      next unless domains.include?(Addressable::URI.parse(subscription.callback_url).host)
       Pubsubhubbub::DeliveryWorker.perform_async(subscription.id, payload)
     end
   rescue ActiveRecord::RecordNotFound

app/workers/soft_block_domain_followers_worker.rb

@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+class SoftBlockDomainFollowersWorker
+  include Sidekiq::Worker
+
+  sidekiq_options queue: 'pull'
+
+  def perform(account_id, domain)
+    Account.find(account_id).followers.where(domain: domain).pluck(:id).each do |follower_id|
+      SoftBlockWorker.perform_async(account_id, follower_id)
+    end
+  end
+end

app/workers/soft_block_worker.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+class SoftBlockWorker
+  include Sidekiq::Worker
+
+  sidekiq_options queue: 'pull'
+
+  def perform(account_id, target_account_id)
+    account        = Account.find(account_id)
+    target_account = Account.find(target_account_id)
+
+    BlockService.new.call(account, target_account)
+    UnblockService.new.call(account, target_account)
+  rescue ActiveRecord::RecordNotFound
+    true
+  end
+end