Fix being able to import more than allowed number of follows (#15384)

* Fix being able to import more than allowed number of follows

Without this commit, if someone tries importing a second list of accounts to
follow before the first one has been processed, this will queue imports for
the two whole lists, even if they exceed the account's allowed number of
outgoing follows.

This commit changes it so the individual queued imports aren't exempt from
the follow limit check (they remain exempt from the rate-limiting check
though).

* Catch validation errors to not re-queue failed follows

Co-authored-by: Claire <claire.github-309c@sitedethib.com>

4 files changed, 23 insertions, 6 deletions

diff --git a/app/models/concerns/account_interactions.rb b/app/models/concerns/account_interactions.rb
index e2c4b8acf..974f57820 100644
--- a/app/models/concerns/account_interactions.rb
+++ b/app/models/concerns/account_interactions.rb
@@ -97,8 +97,8 @@ module AccountInteractions
     has_many :announcement_mutes, dependent: :destroy
   end
 
-  def follow!(other_account, reblogs: nil, notify: nil, uri: nil, rate_limit: false)
-    rel = active_relationships.create_with(show_reblogs: reblogs.nil? ? true : reblogs, notify: notify.nil? ? false : notify, uri: uri, rate_limit: rate_limit)
+  def follow!(other_account, reblogs: nil, notify: nil, uri: nil, rate_limit: false, bypass_limit: false)
+    rel = active_relationships.create_with(show_reblogs: reblogs.nil? ? true : reblogs, notify: notify.nil? ? false : notify, uri: uri, rate_limit: rate_limit, bypass_follow_limit: bypass_limit)
                               .find_or_create_by!(target_account: other_account)
 
     rel.show_reblogs = reblogs unless reblogs.nil?
@@ -111,8 +111,8 @@ module AccountInteractions
     rel
   end
 
-  def request_follow!(other_account, reblogs: nil, notify: nil, uri: nil, rate_limit: false)
-    rel = follow_requests.create_with(show_reblogs: reblogs.nil? ? true : reblogs, notify: notify.nil? ? false : notify, uri: uri, rate_limit: rate_limit)
+  def request_follow!(other_account, reblogs: nil, notify: nil, uri: nil, rate_limit: false, bypass_limit: false)
+    rel = follow_requests.create_with(show_reblogs: reblogs.nil? ? true : reblogs, notify: notify.nil? ? false : notify, uri: uri, rate_limit: rate_limit, bypass_follow_limit: bypass_limit)
                          .find_or_create_by!(target_account: other_account)
 
     rel.show_reblogs = reblogs unless reblogs.nil?
diff --git a/app/models/concerns/follow_limitable.rb b/app/models/concerns/follow_limitable.rb
new file mode 100644
index 000000000..c64060d6e
--- /dev/null
+++ b/app/models/concerns/follow_limitable.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+module FollowLimitable
+  extend ActiveSupport::Concern
+
+  included do
+    validates_with FollowLimitValidator, on: :create, unless: :bypass_follow_limit?
+  end
+
+  def bypass_follow_limit=(value)
+    @bypass_follow_limit = value
+  end
+
+  def bypass_follow_limit?
+    @bypass_follow_limit
+  end
+end
diff --git a/app/models/follow.rb b/app/models/follow.rb
index 69a1722b3..a5e3fe809 100644
--- a/app/models/follow.rb
+++ b/app/models/follow.rb
@@ -17,6 +17,7 @@ class Follow < ApplicationRecord
   include Paginable
   include RelationshipCacheable
   include RateLimitable
+  include FollowLimitable
 
   rate_limit by: :account, family: :follows
 
@@ -26,7 +27,6 @@ class Follow < ApplicationRecord
   has_one :notification, as: :activity, dependent: :destroy
 
   validates :account_id, uniqueness: { scope: :target_account_id }
-  validates_with FollowLimitValidator, on: :create, if: :rate_limit?
 
   scope :recent, -> { reorder(id: :desc) }
 
diff --git a/app/models/follow_request.rb b/app/models/follow_request.rb
index 2d2a77b59..59fefcdf6 100644
--- a/app/models/follow_request.rb
+++ b/app/models/follow_request.rb
@@ -17,6 +17,7 @@ class FollowRequest < ApplicationRecord
   include Paginable
   include RelationshipCacheable
   include RateLimitable
+  include FollowLimitable
 
   rate_limit by: :account, family: :follows
 
@@ -26,7 +27,6 @@ class FollowRequest < ApplicationRecord
   has_one :notification, as: :activity, dependent: :destroy
 
   validates :account_id, uniqueness: { scope: :target_account_id }
-  validates_with FollowLimitValidator, on: :create, if: :rate_limit?
 
   def authorize!
     account.follow!(target_account, reblogs: show_reblogs, notify: notify, uri: uri)