Add notifications of severed relationships

app/controllers/severed_relationships_controller.rb

@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+class SeveredRelationshipsController < ApplicationController
+  layout 'admin'
+
+  before_action :authenticate_user!
+  before_action :set_body_classes
+  before_action :set_cache_headers
+
+  before_action :set_event, only: [:following, :followers]
+
+  def index
+    @events = AccountRelationshipSeveranceEvent.where(account: current_account)
+  end
+
+  def following
+    respond_to do |format|
+      format.csv { send_data following_data, filename: "following-#{@event.target_name}-#{@event.created_at.to_date.iso8601}.csv" }
+    end
+  end
+
+  def followers
+    respond_to do |format|
+      format.csv { send_data followers_data, filename: "followers-#{@event.target_name}-#{@event.created_at.to_date.iso8601}.csv" }
+    end
+  end
+
+  private
+
+  def set_event
+    @event = AccountRelationshipSeveranceEvent.find(params[:id])
+  end
+
+  def following_data
+    CSV.generate(headers: ['Account address', 'Show boosts', 'Notify on new posts', 'Languages'], write_headers: true) do |csv|
+      @event.severed_relationships.active.where(local_account: current_account).includes(:remote_account).reorder(id: :desc).each do |follow|
+        csv << [acct(follow.target_account), follow.show_reblogs, follow.notify, follow.languages&.join(', ')]
+      end
+    end
+  end
+
+  def followers_data
+    CSV.generate(headers: ['Account address'], write_headers: true) do |csv|
+      @event.severed_relationships.passive.where(local_account: current_account).includes(:remote_account).reorder(id: :desc).each do |follow|
+        csv << [acct(follow.account)]
+      end
+    end
+  end
+
+  def acct(account)
+    account.local? ? account.local_username_and_domain : account.acct
+  end
+
+  def set_body_classes
+    @body_classes = 'admin'
+  end
+
+  def set_cache_headers
+    response.cache_control.replace(private: true, no_store: true)
+  end
+end

app/javascript/mastodon/features/notifications/components/notification.jsx

@@ -14,6 +14,7 @@ import EditIcon from '@/material-icons/400-24px/edit.svg?react';
 import FlagIcon from '@/material-icons/400-24px/flag-fill.svg?react';
 import HomeIcon from '@/material-icons/400-24px/home-fill.svg?react';
 import InsertChartIcon from '@/material-icons/400-24px/insert_chart.svg?react';
+import LinkOffIcon from '@/material-icons/400-24px/link_off.svg?react';
 import PersonIcon from '@/material-icons/400-24px/person-fill.svg?react';
 import PersonAddIcon from '@/material-icons/400-24px/person_add-fill.svg?react';
 import RepeatIcon from '@/material-icons/400-24px/repeat.svg?react';
@@ -26,6 +27,7 @@ import { WithRouterPropTypes } from 'mastodon/utils/react_router';
 
 import FollowRequestContainer from '../containers/follow_request_container';
 
+import RelationshipsSeveranceEvent from './relationships_severance_event';
 import Report from './report';
 
 const messages = defineMessages({
@@ -36,6 +38,7 @@ const messages = defineMessages({
   reblog: { id: 'notification.reblog', defaultMessage: '{name} boosted your status' },
   status: { id: 'notification.status', defaultMessage: '{name} just posted' },
   update: { id: 'notification.update', defaultMessage: '{name} edited a post' },
+  severedRelationships: { id: 'notification.severed_relationships', defaultMessage: 'Relationships with {name} severed' },
   adminSignUp: { id: 'notification.admin.sign_up', defaultMessage: '{name} signed up' },
   adminReport: { id: 'notification.admin.report', defaultMessage: '{name} reported {target}' },
 });
@@ -358,6 +361,30 @@ class Notification extends ImmutablePureComponent {
     );
   }
 
+  renderRelationshipsSevered (notification) {
+    const { intl, unread } = this.props;
+
+    if (!notification.get('event')) {
+      return null;
+    }
+
+    return (
+      <HotKeys handlers={this.getHandlers()}>
+        <div className={classNames('notification notification-severed-relationships focusable', { unread })} tabIndex={0} aria-label={notificationForScreenReader(intl, intl.formatMessage(messages.adminReport, { name: notification.getIn(['event', 'target_name']) }), notification.get('created_at'))}>
+          <div className='notification__message'>
+            <Icon id='unlink' icon={LinkOffIcon} />
+
+            <span title={notification.get('created_at')}>
+              <FormattedMessage id='notification.severedRelationships' defaultMessage='Relationships with {name} severed' values={{ name: notification.getIn(['event', 'target_name']) }} />
+            </span>
+          </div>
+
+          <RelationshipsSeveranceEvent event={notification.get('event')} />
+        </div>
+      </HotKeys>
+    );
+  }
+
   renderAdminSignUp (notification, account, link) {
     const { intl, unread } = this.props;
 
@@ -429,6 +456,8 @@ class Notification extends ImmutablePureComponent {
       return this.renderUpdate(notification, link);
     case 'poll':
       return this.renderPoll(notification, account);
+    case 'severed_relationships':
+      return this.renderRelationshipsSevered(notification);
     case 'admin.sign_up':
       return this.renderAdminSignUp(notification, account, link);
     case 'admin.report':

app/javascript/mastodon/features/notifications/components/relationships_severance_event.jsx

@@ -0,0 +1,61 @@
+import PropTypes from 'prop-types';
+
+import { defineMessages, FormattedMessage, useIntl } from 'react-intl';
+
+import ImmutablePropTypes from 'react-immutable-proptypes';
+
+import { RelativeTimestamp } from 'mastodon/components/relative_timestamp';
+
+// This needs to be kept in sync with app/models/relationship_severance_event.rb
+const messages = defineMessages({
+  account_suspension: { id: 'relationship_severance_notification.types.account_suspension', defaultMessage: 'Account has been suspended' },
+  domain_block: { id: 'relationship_severance_notification.types.domain_block', defaultMessage: 'Domain has been suspended' },
+  user_domain_block: { id: 'relationship_severance_notification.types.user_domain_block', defaultMessage: 'You blocked this domain' },
+});
+
+const RelationshipsSeveranceEvent = ({ event, hidden }) => {
+  const intl = useIntl();
+
+  if (hidden || !event) {
+    return null;
+  }
+
+  return (
+    <div className='notification__report'>
+      <div className='notification__report__details'>
+        <div>
+          <RelativeTimestamp timestamp={event.get('created_at')} short={false} />
+          {' · '}
+          { event.get('purged') ? (
+            <FormattedMessage
+              id='relationship_severance_notification.purged_data'
+              defaultMessage='purged by administrators'
+            />
+          ) : (
+            <FormattedMessage
+              id='relationship_severance_notification.relationships'
+              defaultMessage='{count, plural, one {# relationship} other {# relationships}}'
+              values={{ count: event.get('relationships_count', 0) }}
+            />
+          )}
+          <br />
+          <strong>{intl.formatMessage(messages[event.get('type')])}</strong>
+        </div>
+
+        <div className='notification__report__actions'>
+          <a href='/severed_relationships' className='button' target='_blank' rel='noopener noreferrer'>
+            <FormattedMessage id='relationship_severance_notification.view' defaultMessage='View' />
+          </a>
+        </div>
+      </div>
+    </div>
+  );
+
+};
+
+RelationshipsSeveranceEvent.propTypes = {
+  event: ImmutablePropTypes.map.isRequired,
+  hidden: PropTypes.bool,
+};
+
+export default RelationshipsSeveranceEvent;

app/javascript/mastodon/locales/en.json

@@ -471,6 +471,8 @@
   "notification.own_poll": "Your poll has ended",
   "notification.poll": "A poll you have voted in has ended",
   "notification.reblog": "{name} boosted your post",
+  "notification.severedRelationships": "Relationships with {name} severed",
+  "notification.severed_relationships": "Relationships with {name} severed",
   "notification.status": "{name} just posted",
   "notification.update": "{name} edited a post",
   "notification_requests.accept": "Accept",
@@ -587,6 +589,12 @@
   "refresh": "Refresh",
   "regeneration_indicator.label": "Loading…",
   "regeneration_indicator.sublabel": "Your home feed is being prepared!",
+  "relationship_severance_notification.purged_data": "purged by administrators",
+  "relationship_severance_notification.relationships": "{count, plural, one {# relationship} other {# relationships}}",
+  "relationship_severance_notification.types.account_suspension": "Account has been suspended",
+  "relationship_severance_notification.types.domain_block": "Domain has been suspended",
+  "relationship_severance_notification.types.user_domain_block": "You blocked this domain",
+  "relationship_severance_notification.view": "View",
   "relative_time.days": "{number}d",
   "relative_time.full.days": "{number, plural, one {# day} other {# days}} ago",
   "relative_time.full.hours": "{number, plural, one {# hour} other {# hours}} ago",

app/javascript/mastodon/reducers/notifications.js

@@ -55,6 +55,7 @@ export const notificationToMap = notification => ImmutableMap({
   created_at: notification.created_at,
   status: notification.status ? notification.status.id : null,
   report: notification.report ? fromJS(notification.report) : null,
+  event: notification.event ? fromJS(notification.event) : null,
 });
 
 const normalizeNotification = (state, notification, usePendingItems) => {

app/models/account_relationship_severance_event.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+#
+# == Schema Information
+#
+# Table name: account_relationship_severance_events
+#
+#  id                              :bigint(8)        not null, primary key
+#  account_id                      :bigint(8)        not null
+#  relationship_severance_event_id :bigint(8)        not null
+#  created_at                      :datetime         not null
+#  updated_at                      :datetime         not null
+#
+class AccountRelationshipSeveranceEvent < ApplicationRecord
+  belongs_to :account
+  belongs_to :relationship_severance_event
+
+  delegate :severed_relationships, :type, :target_name, :purged, to: :relationship_severance_event, prefix: false
+
+  before_create :set_relationships_count!
+
+  private
+
+  def set_relationships_count!
+    self.relationships_count = severed_relationships.where(local_account: account).count
+  end
+end

app/models/concerns/account/interactions.rb

@@ -83,6 +83,11 @@ def follow_mapping(query, field)
     has_many :following, -> { order('follows.id desc') }, through: :active_relationships,  source: :target_account
     has_many :followers, -> { order('follows.id desc') }, through: :passive_relationships, source: :account
 
+    with_options class_name: 'SeveredRelationship', dependent: :destroy do
+      has_many :severed_relationships, foreign_key: 'local_account_id', inverse_of: :local_account
+      has_many :remote_severed_relationships, foreign_key: 'remote_account_id', inverse_of: :remote_account
+    end
+
     # Account notes
     has_many :account_notes, dependent: :destroy
 

app/models/concerns/account/merging.rb

@@ -48,6 +48,18 @@ def merge_with!(other_account)
       record.update_attribute(:account_warning_id, id)
     end
 
+    SeveredRelationship.where(local_account_id: other_account.id).reorder(nil).find_each do |record|
+      record.update_attribute(:local_account_id, id)
+    rescue ActiveRecord::RecordNotUnique
+      next
+    end
+
+    SeveredRelationship.where(remote_account_id: other_account.id).reorder(nil).find_each do |record|
+      record.update_attribute(:remote_account_id, id)
+    rescue ActiveRecord::RecordNotUnique
+      next
+    end
+
     # Some follow relationships have moved, so the cache is stale
     Rails.cache.delete_matched("followers_hash:#{id}:*")
     Rails.cache.delete_matched("relationships:#{id}:*")

app/models/notification.rb

@@ -54,6 +54,9 @@ class Notification < ApplicationRecord
     update: {
       filterable: false,
     }.freeze,
+    severed_relationships: {
+      filterable: false,
+    }.freeze,
     'admin.sign_up': {
       filterable: false,
     }.freeze,
@@ -86,6 +89,7 @@ class Notification < ApplicationRecord
     belongs_to :favourite, inverse_of: :notification
     belongs_to :poll, inverse_of: false
     belongs_to :report, inverse_of: false
+    belongs_to :relationship_severance_event, inverse_of: false
   end
 
   validates :type, inclusion: { in: TYPES }
@@ -182,6 +186,11 @@ def set_from_account
       self.from_account_id = activity&.status&.account_id
     when 'Account'
       self.from_account_id = activity&.id
+    when 'AccountRelationshipSeveranceEvent'
+      # These do not really have an originating account, but this is mandatory
+      # in the data model, and the recipient's account will by definition
+      # always exist
+      self.from_account_id = account_id
     end
   end
 

app/models/relationship_severance_event.rb

@@ -0,0 +1,56 @@
+# frozen_string_literal: true
+
+# == Schema Information
+#
+# Table name: relationship_severance_events
+#
+#  id          :bigint(8)        not null, primary key
+#  type        :integer          not null
+#  target_name :string           not null
+#  purged      :boolean          default(FALSE), not null
+#  created_at  :datetime         not null
+#  updated_at  :datetime         not null
+#
+class RelationshipSeveranceEvent < ApplicationRecord
+  self.inheritance_column = nil
+
+  has_many :severed_relationships, inverse_of: :relationship_severance_event, dependent: :delete_all
+
+  enum type: {
+    domain_block: 0,
+    user_domain_block: 1,
+    account_suspension: 2,
+  }
+
+  scope :about_local_account, ->(account) { where(id: SeveredRelationship.about_local_account(account).select(:relationship_severance_event_id)) }
+
+  def import_from_active_follows!(follows)
+    import_from_follows!(follows, true)
+  end
+
+  def import_from_passive_follows!(follows)
+    import_from_follows!(follows, false)
+  end
+
+  def affected_local_accounts
+    Account.where(id: severed_relationships.select(:local_account_id))
+  end
+
+  private
+
+  def import_from_follows!(follows, active)
+    SeveredRelationship.insert_all(
+      follows.pluck(:account_id, :target_account_id, :show_reblogs, :notify, :languages).map do |account_id, target_account_id, show_reblogs, notify, languages|
+        {
+          local_account_id: active ? account_id : target_account_id,
+          remote_account_id: active ? target_account_id : account_id,
+          show_reblogs: show_reblogs,
+          notify: notify,
+          languages: languages,
+          relationship_severance_event_id: id,
+          direction: active ? :active : :passive,
+        }
+      end
+    )
+  end
+end