Add local followers page to admin account UI (#9610)

* Add local followers page to admin account UI

For moderation, I often find myself wondering who, locally, is following
a remote user. Currently, to see this, I have to go back to the web UI,
paste in their full handle, click their profile, and go to the
"Followers" tab (plus, this information is incidental, and if mastodon
ever decides to resolve all of the follower information, there will be
no place local followers are shown). This PR adds a new page which is
accessible via the "following" count on the admin's account view
page, which shows the local followers. (It has filter parameters for
account location to indicate that only local followers are shown, and
leave room for expansion if mastodon ever decides to store the entire
remote follow list).

* Normalize en.yml

4 files changed, 58 insertions, 1 deletions

diff --git a/app/controllers/admin/followers_controller.rb b/app/controllers/admin/followers_controller.rb
new file mode 100644
index 000000000..819628b20
--- /dev/null
+++ b/app/controllers/admin/followers_controller.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module Admin
+  class FollowersController < BaseController
+    before_action :set_account
+
+    PER_PAGE = 40
+
+    def index
+      authorize :account, :index?
+      @followers = followers.recent.page(params[:page]).per(PER_PAGE)
+    end
+
+    def set_account
+      @account = Account.find(params[:account_id])
+    end
+
+    def followers
+      Follow.includes(:account).where(target_account: @account)
+    end
+  end
+end
diff --git a/app/models/account.rb b/app/models/account.rb
index cf804fc67..66f02b27d 100644
--- a/app/models/account.rb
+++ b/app/models/account.rb
@@ -139,6 +139,10 @@ class Account < ApplicationRecord
     "#{username}@#{Rails.configuration.x.local_domain}"
   end
 
+  def local_followers_count
+    Follow.where(target_account_id: id).count
+  end
+
   def to_webfinger_s
     "acct:#{local_username_and_domain}"
   end
diff --git a/app/views/admin/accounts/show.html.haml b/app/views/admin/accounts/show.html.haml
index 226aef732..47cf41073 100644
--- a/app/views/admin/accounts/show.html.haml
+++ b/app/views/admin/accounts/show.html.haml
@@ -89,7 +89,9 @@
         %td= number_to_human @account.following_count
       %tr
         %th= t('admin.accounts.followers')
-        %td= number_to_human @account.followers_count
+        %td
+          = number_to_human @account.followers_count
+          = link_to t('admin.accounts.followers_local', local: number_to_human(@account.local_followers_count)), admin_account_followers_path(@account.id)
       %tr
         %th= t('admin.accounts.statuses')
         %td= link_to number_to_human(@account.statuses_count), admin_account_statuses_path(@account.id)
diff --git a/app/views/admin/followers/index.html.haml b/app/views/admin/followers/index.html.haml
new file mode 100644
index 000000000..baf34bc95
--- /dev/null
+++ b/app/views/admin/followers/index.html.haml
@@ -0,0 +1,29 @@
+- content_for :header_tags do
+  = javascript_pack_tag 'admin', integrity: true, async: true, crossorigin: 'anonymous'
+
+- content_for :page_title do
+  = t('admin.followers.title', acct: @account.acct)
+
+.filters
+  .filter-subset
+    %strong= t('admin.accounts.location.title')
+    %ul
+      %li= link_to t('admin.accounts.location.local'), admin_account_followers_path(@account.id), class: 'selected'
+  .back-link{ style: 'flex: 1 1 auto; text-align: right' }
+    = link_to admin_account_path(@account.id) do
+      %i.fa.fa-chevron-left.fa-fw
+      = t('admin.followers.back_to_account')
+
+.table-wrapper
+  %table.table
+    %thead
+      %tr
+        %th= t('admin.accounts.username')
+        %th= t('admin.accounts.role')
+        %th= t('admin.accounts.most_recent_ip')
+        %th= t('admin.accounts.most_recent_activity')
+        %th
+    %tbody
+      = render partial: 'admin/accounts/account', collection: @followers.map{|a| a.account}
+
+= paginate @followers