Add account migration UI (#11846)

Fix #10736

- Change data export to be available for non-functional accounts
- Change non-functional accounts to include redirecting accounts

app/controllers/concerns/export_controller_concern.rb

@@ -5,7 +5,10 @@ module ExportControllerConcern
 
   included do
     before_action :authenticate_user!
+    before_action :require_not_suspended!
     before_action :load_export
+
+    skip_before_action :require_functional!
   end
 
   private
@@ -27,4 +30,8 @@ module ExportControllerConcern
   def export_filename
     "#{controller_name}.csv"
   end
+
+  def require_not_suspended!
+    forbidden if current_account.suspended?
+  end
 end

app/controllers/settings/aliases_controller.rb

@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+class Settings::AliasesController < Settings::BaseController
+  layout 'admin'
+
+  before_action :authenticate_user!
+  before_action :set_aliases, except: :destroy
+  before_action :set_alias, only: :destroy
+
+  def index
+    @alias = current_account.aliases.build
+  end
+
+  def create
+    @alias = current_account.aliases.build(resource_params)
+
+    if @alias.save
+      redirect_to settings_aliases_path, notice: I18n.t('aliases.created_msg')
+    else
+      render :show
+    end
+  end
+
+  def destroy
+    @alias.destroy!
+    redirect_to settings_aliases_path, notice: I18n.t('aliases.deleted_msg')
+  end
+
+  private
+
+  def resource_params
+    params.require(:account_alias).permit(:acct)
+  end
+
+  def set_alias
+    @alias = current_account.aliases.find(params[:id])
+  end
+
+  def set_aliases
+    @aliases = current_account.aliases.order(id: :desc).reject(&:new_record?)
+  end
+end

app/controllers/settings/exports_controller.rb

@@ -6,6 +6,9 @@ class Settings::ExportsController < Settings::BaseController
   layout 'admin'
 
   before_action :authenticate_user!
+  before_action :require_not_suspended!
+
+  skip_before_action :require_functional!
 
   def show
     @export  = Export.new(current_account)
@@ -34,4 +37,8 @@ class Settings::ExportsController < Settings::BaseController
   def lock_options
     { redis: Redis.current, key: "backup:#{current_user.id}" }
   end
+
+  def require_not_suspended!
+    forbidden if current_account.suspended?
+  end
 end

app/controllers/settings/migrations_controller.rb

@@ -4,31 +4,59 @@ class Settings::MigrationsController < Settings::BaseController
   layout 'admin'
 
   before_action :authenticate_user!
+  before_action :require_not_suspended!
+  before_action :set_migrations
+  before_action :set_cooldown
+
+  skip_before_action :require_functional!
 
   def show
-    @migration = Form::Migration.new(account: current_account.moved_to_account)
+    @migration = current_account.migrations.build
   end
 
-  def update
-    @migration = Form::Migration.new(resource_params)
+  def create
+    @migration = current_account.migrations.build(resource_params)
 
-    if @migration.valid? && migration_account_changed?
-      current_account.update!(moved_to_account: @migration.account)
+    if @migration.save_with_challenge(current_user)
+      current_account.update!(moved_to_account: @migration.target_account)
       ActivityPub::UpdateDistributionWorker.perform_async(current_account.id)
-      redirect_to settings_migration_path, notice: I18n.t('migrations.updated_msg')
+      ActivityPub::MoveDistributionWorker.perform_async(@migration.id)
+      redirect_to settings_migration_path, notice: I18n.t('migrations.moved_msg', acct: current_account.moved_to_account.acct)
     else
       render :show
     end
   end
 
+  def cancel
+    if current_account.moved_to_account_id.present?
+      current_account.update!(moved_to_account: nil)
+      ActivityPub::UpdateDistributionWorker.perform_async(current_account.id)
+    end
+
+    redirect_to settings_migration_path, notice: I18n.t('migrations.cancelled_msg')
+  end
+
+  helper_method :on_cooldown?
+
   private
 
   def resource_params
-    params.require(:migration).permit(:acct)
+    params.require(:account_migration).permit(:acct, :current_password, :current_username)
+  end
+
+  def set_migrations
+    @migrations = current_account.migrations.includes(:target_account).order(id: :desc).reject(&:new_record?)
+  end
+
+  def set_cooldown
+    @cooldown = current_account.migrations.within_cooldown.first
+  end
+
+  def on_cooldown?
+    @cooldown.present?
   end
 
-  def migration_account_changed?
-    current_account.moved_to_account_id != @migration.account&.id &&
-      current_account.id != @migration.account&.id
+  def require_not_suspended!
+    forbidden if current_account.suspended?
   end
 end

app/helpers/settings_helper.rb

@@ -87,4 +87,12 @@ module SettingsHelper
       'desktop'
     end
   end
+
+  def compact_account_link_to(account)
+    return if account.nil?
+
+    link_to ActivityPub::TagManager.instance.url_for(account), class: 'name-tag', title: account.acct do
+      safe_join([image_tag(account.avatar.url, width: 15, height: 15, alt: display_name(account), class: 'avatar'), content_tag(:span, account.acct, class: 'username')], ' ')
+    end
+  end
 end

app/models/account_alias.rb

@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+# == Schema Information
+#
+# Table name: account_aliases
+#
+#  id         :bigint(8)        not null, primary key
+#  account_id :bigint(8)
+#  acct       :string           default(""), not null
+#  uri        :string           default(""), not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+
+class AccountAlias < ApplicationRecord
+  belongs_to :account
+
+  validates :acct, presence: true, domain: { acct: true }
+  validates :uri, presence: true
+
+  before_validation :set_uri
+  after_create :add_to_account
+  after_destroy :remove_from_account
+
+  private
+
+  def set_uri
+    target_account = ResolveAccountService.new.call(acct)
+    self.uri       = ActivityPub::TagManager.instance.uri_for(target_account) unless target_account.nil?
+  rescue Goldfinger::Error, HTTP::Error, OpenSSL::SSL::SSLError, Mastodon::Error
+    # Validation will take care of it
+  end
+
+  def add_to_account
+    account.update(also_known_as: account.also_known_as + [uri])
+  end
+
+  def remove_from_account
+    account.update(also_known_as: account.also_known_as.reject { |x| x == uri })
+  end
+end

app/models/account_migration.rb

@@ -0,0 +1,74 @@
+# frozen_string_literal: true
+
+# == Schema Information
+#
+# Table name: account_migrations
+#
+#  id                :bigint(8)        not null, primary key
+#  account_id        :bigint(8)
+#  acct              :string           default(""), not null
+#  followers_count   :bigint(8)        default(0), not null
+#  target_account_id :bigint(8)
+#  created_at        :datetime         not null
+#  updated_at        :datetime         not null
+#
+
+class AccountMigration < ApplicationRecord
+  COOLDOWN_PERIOD = 30.days.freeze
+
+  belongs_to :account
+  belongs_to :target_account, class_name: 'Account'
+
+  before_validation :set_target_account
+  before_validation :set_followers_count
+
+  validates :acct, presence: true, domain: { acct: true }
+  validate :validate_migration_cooldown
+  validate :validate_target_account
+
+  scope :within_cooldown, ->(now = Time.now.utc) { where(arel_table[:created_at].gteq(now - COOLDOWN_PERIOD)) }
+
+  attr_accessor :current_password, :current_username
+
+  def save_with_challenge(current_user)
+    if current_user.encrypted_password.present?
+      errors.add(:current_password, :invalid) unless current_user.valid_password?(current_password)
+    else
+      errors.add(:current_username, :invalid) unless account.username == current_username
+    end
+
+    return false unless errors.empty?
+
+    save
+  end
+
+  def cooldown_at
+    created_at + COOLDOWN_PERIOD
+  end
+
+  private
+
+  def set_target_account
+    self.target_account = ResolveAccountService.new.call(acct)
+  rescue Goldfinger::Error, HTTP::Error, OpenSSL::SSL::SSLError, Mastodon::Error
+    # Validation will take care of it
+  end
+
+  def set_followers_count
+    self.followers_count = account.followers_count
+  end
+
+  def validate_target_account
+    if target_account.nil?
+      errors.add(:acct, I18n.t('migrations.errors.not_found'))
+    else
+      errors.add(:acct, I18n.t('migrations.errors.missing_also_known_as')) unless target_account.also_known_as.include?(ActivityPub::TagManager.instance.uri_for(account))
+      errors.add(:acct, I18n.t('migrations.errors.already_moved')) if account.moved_to_account_id.present? && account.moved_to_account_id == target_account.id
+      errors.add(:acct, I18n.t('migrations.errors.move_to_self')) if account.id == target_account.id
+    end
+  end
+
+  def validate_migration_cooldown
+    errors.add(:base, I18n.t('migrations.errors.on_cooldown')) if account.migrations.within_cooldown.exists?
+  end
+end

app/models/concerns/account_associations.rb

@@ -52,6 +52,8 @@ module AccountAssociations
 
     # Account migrations
     belongs_to :moved_to_account, class_name: 'Account', optional: true
+    has_many :migrations, class_name: 'AccountMigration', dependent: :destroy, inverse_of: :account
+    has_many :aliases, class_name: 'AccountAlias', dependent: :destroy, inverse_of: :account
 
     # Hashtags
     has_and_belongs_to_many :tags

app/models/form/migration.rb

@@ -1,25 +0,0 @@
-# frozen_string_literal: true
-
-class Form::Migration
-  include ActiveModel::Validations
-
-  attr_accessor :acct, :account
-
-  def initialize(attrs = {})
-    @account = attrs[:account]
-    @acct    = attrs[:account].acct unless @account.nil?
-    @acct    = attrs[:acct].gsub(/\A@/, '').strip unless attrs[:acct].nil?
-  end
-
-  def valid?
-    return false unless super
-    set_account
-    errors.empty?
-  end
-
-  private
-
-  def set_account
-    self.account = (ResolveAccountService.new.call(acct) if account.nil? && acct.present?)
-  end
-end

app/models/remote_follow.rb

@@ -49,7 +49,7 @@ class RemoteFollow
   end
 
   def fetch_template!
-    return missing_resource if acct.blank?
+    return missing_resource_error if acct.blank?
 
     _, domain = acct.split('@')
 

app/models/user.rb

@@ -168,7 +168,7 @@ class User < ApplicationRecord
   end
 
   def functional?
-    confirmed? && approved? && !disabled? && !account.suspended?
+    confirmed? && approved? && !disabled? && !account.suspended? && account.moved_to_account_id.nil?
   end
 
   def unconfirmed_or_pending?

app/serializers/activitypub/move_serializer.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+class ActivityPub::MoveSerializer < ActivityPub::Serializer
+  attributes :id, :type, :target, :actor
+  attribute :virtual_object, key: :object
+
+  def id
+    [ActivityPub::TagManager.instance.uri_for(object.account), '#moves/', object.id].join
+  end
+
+  def type
+    'Move'
+  end
+
+  def target
+    ActivityPub::TagManager.instance.uri_for(object.target_account)
+  end
+
+  def virtual_object
+    ActivityPub::TagManager.instance.uri_for(object.account)
+  end
+
+  def actor
+    ActivityPub::TagManager.instance.uri_for(object.account)
+  end
+end

app/views/auth/registrations/_status.html.haml

@@ -1,16 +1,22 @@
 %h3= t('auth.status.account_status')
 
-- if @user.account.suspended?
-  %span.negative-hint= t('user_mailer.warning.explanation.suspend')
-- elsif @user.disabled?
-  %span.negative-hint= t('user_mailer.warning.explanation.disable')
-- elsif @user.account.silenced?
-  %span.warning-hint= t('user_mailer.warning.explanation.silence')
-- elsif !@user.confirmed?
-  %span.warning-hint= t('auth.status.confirming')
-- elsif !@user.approved?
-  %span.warning-hint= t('auth.status.pending')
-- else
-  %span.positive-hint= t('auth.status.functional')
+.simple_form
+  %p.hint
+    - if @user.account.suspended?
+      %span.negative-hint= t('user_mailer.warning.explanation.suspend')
+    - elsif @user.disabled?
+      %span.negative-hint= t('user_mailer.warning.explanation.disable')
+    - elsif @user.account.silenced?
+      %span.warning-hint= t('user_mailer.warning.explanation.silence')
+    - elsif !@user.confirmed?
+      %span.warning-hint= t('auth.status.confirming')
+      = link_to t('auth.didnt_get_confirmation'), new_user_confirmation_path
+    - elsif !@user.approved?
+      %span.warning-hint= t('auth.status.pending')
+    - elsif @user.account.moved_to_account_id.present?
+      %span.positive-hint= t('auth.status.redirecting_to', acct: @user.account.moved_to_account.acct)
+      = link_to t('migrations.cancel'), settings_migration_path
+    - else
+      %span.positive-hint= t('auth.status.functional')
 
 %hr.spacer/

app/views/auth/registrations/edit.html.haml

@@ -13,7 +13,7 @@
       .fields-row__column.fields-group.fields-row__column-6
         = f.input :email, wrapper: :with_label, input_html: { 'aria-label' => t('simple_form.labels.defaults.email') }, required: true, disabled: current_account.suspended?
       .fields-row__column.fields-group.fields-row__column-6
-        = f.input :current_password, wrapper: :with_label, input_html: { 'aria-label' => t('simple_form.labels.defaults.current_password'), :autocomplete => 'off' }, required: true, disabled: current_account.suspended?
+        = f.input :current_password, wrapper: :with_label, input_html: { 'aria-label' => t('simple_form.labels.defaults.current_password'), :autocomplete => 'off' }, required: true, disabled: current_account.suspended?, hint: false
 
     .fields-row
       .fields-row__column.fields-group.fields-row__column-6

app/views/settings/aliases/index.html.haml

@@ -0,0 +1,29 @@
+- content_for :page_title do
+  = t('settings.aliases')
+
+= simple_form_for @alias, url: settings_aliases_path do |f|
+  = render 'shared/error_messages', object: @alias
+
+  %p.hint= t('aliases.hint_html')
+
+  %hr.spacer/
+
+  .fields-group
+    = f.input :acct, wrapper: :with_block_label, input_html: { autocapitalize: 'none', autocorrect: 'off' }
+
+  .actions
+    = f.button :button, t('aliases.add_new'), type: :submit, class: 'button'
+
+%hr.spacer/
+
+.table-wrapper
+  %table.table.inline-table
+    %thead
+      %tr
+        %th= t('simple_form.labels.account_alias.acct')
+        %th
+    %tbody
+      - @aliases.each do |account_alias|
+        %tr
+          %td= account_alias.acct
+          %td= table_link_to 'trash', t('aliases.remove'), settings_alias_path(account_alias), data: { method: :delete }

app/views/settings/exports/show.html.haml

@@ -37,12 +37,16 @@
         %td= number_with_delimiter @export.total_domain_blocks
         %td= table_link_to 'download', t('exports.csv'), settings_exports_domain_blocks_path(format: :csv)
 
+%hr.spacer/
+
 %p.muted-hint= t('exports.archive_takeout.hint_html')
 
 - if policy(:backup).create?
   %p= link_to t('exports.archive_takeout.request'), settings_export_path, class: 'button', method: :post
 
 - unless @backups.empty?
+  %hr.spacer/
+
   .table-wrapper
     %table.table
       %thead

app/views/settings/migrations/show.html.haml

@@ -1,17 +1,85 @@
 - content_for :page_title do
   = t('settings.migrate')
 
-= simple_form_for @migration, as: :migration, url: settings_migration_path, html: { method: :put } do |f|
-  - if @migration.account
-    %p.hint= t('migrations.currently_redirecting')
+.simple_form
+  - if current_account.moved_to_account.present?
+    .fields-row
+      .fields-row__column.fields-group.fields-row__column-6
+        = render 'application/card', account: current_account.moved_to_account
+      .fields-row__column.fields-group.fields-row__column-6
+        %p.hint
+          %span.positive-hint= t('migrations.redirecting_to', acct: current_account.moved_to_account.acct)
 
-    .fields-group
-      = render partial: 'application/card', locals: { account: @migration.account }
+        %p.hint= t('migrations.cancel_explanation')
+
+        %p.hint= link_to t('migrations.cancel'), cancel_settings_migration_path, data: { method: :post }
+  - else
+    %p.hint
+      %span.positive-hint= t('migrations.not_redirecting')
+
+%hr.spacer/
+
+%h3= t 'migrations.proceed_with_move'
+
+= simple_form_for @migration, url: settings_migration_path do |f|
+  - if on_cooldown?
+    %span.warning-hint= t('migrations.on_cooldown', count: ((@cooldown.cooldown_at - Time.now.utc) / 1.day.seconds).ceil)
+  - else
+    %p.hint= t('migrations.warning.before')
+
+    %ul.hint
+      %li.warning-hint= t('migrations.warning.followers')
+      %li.warning-hint= t('migrations.warning.other_data')
+      %li.warning-hint= t('migrations.warning.backreference_required')
+      %li.warning-hint= t('migrations.warning.cooldown')
+      %li.warning-hint= t('migrations.warning.disabled_account')
+
+  %hr.spacer/
 
   = render 'shared/error_messages', object: @migration
 
-  .fields-group
-    = f.input :acct, placeholder: t('migrations.acct')
+  .fields-row
+    .fields-row__column.fields-group.fields-row__column-6
+      = f.input :acct, wrapper: :with_block_label, input_html: { autocapitalize: 'none', autocorrect: 'off' }, disabled: on_cooldown?
+
+    .fields-row__column.fields-group.fields-row__column-6
+      - if current_user.encrypted_password.present?
+        = f.input :current_password, wrapper: :with_block_label, input_html: { :autocomplete => 'off' }, required: true, disabled: on_cooldown?
+      - else
+        = f.input :current_username, wrapper: :with_block_label, input_html: { :autocomplete => 'off' }, required: true, disabled: on_cooldown?
 
   .actions
-    = f.button :button, t('migrations.proceed'), type: :submit, class: 'negative'
+    = f.button :button, t('migrations.proceed_with_move'), type: :submit, class: 'button button--destructive', disabled: on_cooldown?
+
+- unless @migrations.empty?
+  %hr.spacer/
+
+  %h3= t 'migrations.past_migrations'
+
+  %hr.spacer/
+
+  .table-wrapper
+    %table.table.inline-table
+      %thead
+        %tr
+          %th= t('migrations.acct')
+          %th= t('migrations.followers_count')
+          %th
+      %tbody
+        - @migrations.each do |migration|
+          %tr
+            %td
+              - if migration.target_account.present?
+                = compact_account_link_to migration.target_account
+              - else
+                = migration.acct
+
+            %td= number_with_delimiter migration.followers_count
+
+            %td
+              %time.time-ago{ datetime: migration.created_at.iso8601, title: l(migration.created_at) }= l(migration.created_at)
+
+%hr.spacer/
+
+%h3= t 'migrations.incoming_migrations'
+%p.muted-hint= t('migrations.incoming_migrations_html', path: settings_aliases_path)

app/views/settings/profiles/show.html.haml

@@ -60,6 +60,11 @@
 %h6= t('auth.migrate_account')
 %p.muted-hint= t('auth.migrate_account_html', path: settings_migration_path)
 
+%hr.spacer/
+
+%h6= t 'migrations.incoming_migrations'
+%p.muted-hint= t('migrations.incoming_migrations_html', path: settings_aliases_path)
+
 - if open_deletion?
   %hr.spacer/
 

app/workers/activitypub/move_distribution_worker.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+class ActivityPub::MoveDistributionWorker
+  include Sidekiq::Worker
+  include Payloadable
+
+  sidekiq_options queue: 'push'
+
+  def perform(migration_id)
+    @migration = AccountMigration.find(migration_id)
+
+    ActivityPub::DeliveryWorker.push_bulk(inboxes) do |inbox_url|
+      [signed_payload, @account.id, inbox_url]
+    end
+
+    ActivityPub::DeliveryWorker.push_bulk(Relay.enabled.pluck(:inbox_url)) do |inbox_url|
+      [signed_payload, @account.id, inbox_url]
+    end
+  rescue ActiveRecord::RecordNotFound
+    true
+  end
+
+  private
+
+  def inboxes
+    @inboxes ||= @migration.account.followers.inboxes
+  end
+
+  def signed_payload
+    @signed_payload ||= Oj.dump(serialize_payload(@migration, ActivityPub::MoveSerializer, signer: @account))
+  end
+end

config/locales/en.yml

@@ -554,6 +554,12 @@ en:
     new_trending_tag:
       body: 'The hashtag #%{name} is trending today, but has not been previously reviewed. It will not be displayed publicly unless you allow it to, or just save the form as it is to never hear about it again.'
       subject: New hashtag up for review on %{instance} (#%{name})
+  aliases:
+    add_new: Create alias
+    created_msg: Successfully created a new alias. You can now initiate the move from the old account.
+    deleted_msg: Successfully remove the alias. Moving from that account to this one will no longer be possible.
+    hint_html: If you want to move from another account to this one, here you can create an alias, which is required before you can proceed with moving followers from the old account to this one. This action by itself is <strong>harmless and reversible</strong>. <strong>The account migration is initiated from the old account</strong>.
+    remove: Unlink alias
   appearance:
     advanced_web_interface: Advanced web interface
     advanced_web_interface_hint: 'If you want to make use of your entire screen width, the advanced web interface allows you to configure many different columns to see as much information at the same time as you want: Home, notifications, federated timeline, any number of lists and hashtags.'
@@ -613,6 +619,7 @@ en:
       confirming: Waiting for e-mail confirmation to be completed.
       functional: Your account is fully operational.
       pending: Your application is pending review by our staff. This may take some time. You will receive an e-mail if your application is approved.
+      redirecting_to: Your account is inactive because it is currently redirecting to %{acct}.
     trouble_logging_in: Trouble logging in?
   authorize_follow:
     already_following: You are already following this account
@@ -801,10 +808,32 @@ en:
       images_and_video: Cannot attach a video to a status that already contains images
       too_many: Cannot attach more than 4 files
   migrations:
-    acct: username@domain of the new account
-    currently_redirecting: 'Your profile is set to redirect to:'
-    proceed: Save
-    updated_msg: Your account migration setting successfully updated!
+    acct: Moved to
+    cancel: Cancel redirect
+    cancel_explanation: Cancelling the redirect will re-activate your current account, but will not bring back followers that have been moved to that account.
+    cancelled_msg: Successfully cancelled the redirect.
+    errors:
+      already_moved: is the same account you have already moved to
+      missing_also_known_as: is not back-referencing this account
+      move_to_self: cannot be current account
+      not_found: could not be found
+      on_cooldown: You are on cooldown
+    followers_count: Followers at time of move
+    incoming_migrations: Moving from a different account
+    incoming_migrations_html: To move from another account to this one, first you need to <a href="%{path}">create an account alias</a>.
+    moved_msg: Your account is now redirecting to %{acct} and your followers are being moved over.
+    not_redirecting: Your account is not redirecting to any other account currently.
+    on_cooldown: You have recently migrated your account. This function will become available again in %{count} days.
+    past_migrations: Past migrations
+    proceed_with_move: Move followers
+    redirecting_to: Your account is redirecting to %{acct}.
+    warning:
+      backreference_required: The new account must first be configured to back-reference this one
+      before: 'Before proceeding, please read these notes carefully:'
+      cooldown: After moving there is a cooldown period during which you will not be able to move again
+      disabled_account: Your current account will not be fully usable afterwards. However, you will have access to data export as well as re-activation.
+      followers: This action will move all followers from the current account to the new account
+      other_data: No other data will be moved automatically
   moderation:
     title: Moderation
   notification_mailer:
@@ -950,6 +979,7 @@ en:
   settings:
     account: Account
     account_settings: Account settings
+    aliases: Account aliases
     appearance: Appearance
     authorized_apps: Authorized apps
     back: Back to Mastodon

config/locales/simple_form.en.yml

@@ -2,6 +2,10 @@
 en:
   simple_form:
     hints:
+      account_alias:
+        acct: Specify the username@domain of the account you want to move from
+      account_migration:
+        acct: Specify the username@domain of the account you want to move to
       account_warning_preset:
         text: You can use toot syntax, such as URLs, hashtags and mentions
       admin_account_action:
@@ -15,6 +19,8 @@ en:
         avatar: PNG, GIF or JPG. At most %{size}. Will be downscaled to %{dimensions}px
         bot: This account mainly performs automated actions and might not be monitored
         context: One or multiple contexts where the filter should apply
+        current_password: For security purposes please enter the password of the current account
+        current_username: To confirm, please enter the username of the current account
         digest: Only sent after a long period of inactivity and only if you have received any personal messages in your absence
         discoverable: The profile directory is another way by which your account can reach a wider audience
         email: You will be sent a confirmation e-mail
@@ -60,6 +66,10 @@ en:
         fields:
           name: Label
           value: Content
+      account_alias:
+        acct: Handle of the old account
+      account_migration:
+        acct: Handle of the new account
       account_warning_preset:
         text: Preset text
       admin_account_action:

config/navigation.rb

@@ -5,7 +5,7 @@ SimpleNavigation::Configuration.run do |navigation|
     n.item :web, safe_join([fa_icon('chevron-left fw'), t('settings.back')]), root_url
 
     n.item :profile, safe_join([fa_icon('user fw'), t('settings.profile')]), settings_profile_url, if: -> { current_user.functional? } do |s|
-      s.item :profile, safe_join([fa_icon('pencil fw'), t('settings.appearance')]), settings_profile_url, highlights_on: %r{/settings/profile|/settings/migration}
+      s.item :profile, safe_join([fa_icon('pencil fw'), t('settings.appearance')]), settings_profile_url
       s.item :featured_tags, safe_join([fa_icon('hashtag fw'), t('settings.featured_tags')]), settings_featured_tags_url
       s.item :identity_proofs, safe_join([fa_icon('key fw'), t('settings.identity_proofs')]), settings_identity_proofs_path, highlights_on: %r{/settings/identity_proofs*}, if: proc { current_account.identity_proofs.exists? }
     end
@@ -20,13 +20,13 @@ SimpleNavigation::Configuration.run do |navigation|
     n.item :filters, safe_join([fa_icon('filter fw'), t('filters.index.title')]), filters_path, highlights_on: %r{/filters}, if: -> { current_user.functional? }
 
     n.item :security, safe_join([fa_icon('lock fw'), t('settings.account')]), edit_user_registration_url do |s|
-      s.item :password, safe_join([fa_icon('lock fw'), t('settings.account_settings')]), edit_user_registration_url, highlights_on: %r{/auth/edit|/settings/delete}
+      s.item :password, safe_join([fa_icon('lock fw'), t('settings.account_settings')]), edit_user_registration_url, highlights_on: %r{/auth/edit|/settings/delete|/settings/migration|/settings/aliases}
       s.item :two_factor_authentication, safe_join([fa_icon('mobile fw'), t('settings.two_factor_authentication')]), settings_two_factor_authentication_url, highlights_on: %r{/settings/two_factor_authentication}
       s.item :authorized_apps, safe_join([fa_icon('list fw'), t('settings.authorized_apps')]), oauth_authorized_applications_url
     end
 
-    n.item :data, safe_join([fa_icon('cloud-download fw'), t('settings.import_and_export')]), settings_export_url, if: -> { current_user.functional? } do |s|
-      s.item :import, safe_join([fa_icon('cloud-upload fw'), t('settings.import')]), settings_import_url
+    n.item :data, safe_join([fa_icon('cloud-download fw'), t('settings.import_and_export')]), settings_export_url do |s|
+      s.item :import, safe_join([fa_icon('cloud-upload fw'), t('settings.import')]), settings_import_url, if: -> { current_user.functional? }
       s.item :export, safe_join([fa_icon('cloud-download fw'), t('settings.export')]), settings_export_url
     end
 

config/routes.rb

@@ -134,8 +134,14 @@ Rails.application.routes.draw do
     end
 
     resource :delete, only: [:show, :destroy]
-    resource :migration, only: [:show, :update]
 
+    resource :migration, only: [:show, :create] do
+      collection do
+        post :cancel
+      end
+    end
+
+    resources :aliases, only: [:index, :create, :destroy]
     resources :sessions, only: [:destroy]
     resources :featured_tags, only: [:index, :create, :destroy]
   end

db/migrate/20190914202517_create_account_migrations.rb

@@ -0,0 +1,12 @@
+class CreateAccountMigrations < ActiveRecord::Migration[5.2]
+  def change
+    create_table :account_migrations do |t|
+      t.belongs_to :account, foreign_key: { on_delete: :cascade }
+      t.string :acct, null: false, default: ''
+      t.bigint :followers_count, null: false, default: 0
+      t.belongs_to :target_account, foreign_key: { to_table: :accounts, on_delete: :nullify }
+
+      t.timestamps
+    end
+  end
+end

db/migrate/20190915194355_create_account_aliases.rb

@@ -0,0 +1,11 @@
+class CreateAccountAliases < ActiveRecord::Migration[5.2]
+  def change
+    create_table :account_aliases do |t|
+      t.belongs_to :account, foreign_key: { on_delete: :cascade }
+      t.string :acct, null: false, default: ''
+      t.string :uri, null: false, default: ''
+
+      t.timestamps
+    end
+  end
+end

db/schema.rb

@@ -15,6 +15,15 @@ ActiveRecord::Schema.define(version: 2019_09_17_213523) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
+  create_table "account_aliases", force: :cascade do |t|
+    t.bigint "account_id"
+    t.string "acct", default: "", null: false
+    t.string "uri", default: "", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["account_id"], name: "index_account_aliases_on_account_id"
+  end
+
   create_table "account_conversations", force: :cascade do |t|
     t.bigint "account_id"
     t.bigint "conversation_id"
@@ -49,6 +58,17 @@ ActiveRecord::Schema.define(version: 2019_09_17_213523) do
     t.index ["account_id"], name: "index_account_identity_proofs_on_account_id"
   end
 
+  create_table "account_migrations", force: :cascade do |t|
+    t.bigint "account_id"
+    t.string "acct", default: "", null: false
+    t.bigint "followers_count", default: 0, null: false
+    t.bigint "target_account_id"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["account_id"], name: "index_account_migrations_on_account_id"
+    t.index ["target_account_id"], name: "index_account_migrations_on_target_account_id"
+  end
+
   create_table "account_moderation_notes", force: :cascade do |t|
     t.text "content", null: false
     t.bigint "account_id", null: false
@@ -768,10 +788,13 @@ ActiveRecord::Schema.define(version: 2019_09_17_213523) do
     t.index ["user_id"], name: "index_web_settings_on_user_id", unique: true
   end
 
+  add_foreign_key "account_aliases", "accounts", on_delete: :cascade
   add_foreign_key "account_conversations", "accounts", on_delete: :cascade
   add_foreign_key "account_conversations", "conversations", on_delete: :cascade
   add_foreign_key "account_domain_blocks", "accounts", name: "fk_206c6029bd", on_delete: :cascade
   add_foreign_key "account_identity_proofs", "accounts", on_delete: :cascade
+  add_foreign_key "account_migrations", "accounts", column: "target_account_id", on_delete: :nullify
+  add_foreign_key "account_migrations", "accounts", on_delete: :cascade
   add_foreign_key "account_moderation_notes", "accounts"
   add_foreign_key "account_moderation_notes", "accounts", column: "target_account_id"
   add_foreign_key "account_pins", "accounts", column: "target_account_id", on_delete: :cascade

spec/controllers/settings/migrations_controller_spec.rb

@@ -21,6 +21,7 @@ describe Settings::MigrationsController do
 
       let(:user) { Fabricate(:user, account: account) }
       let(:account) { Fabricate(:account, moved_to_account: moved_to_account) }
+
       before { sign_in user, scope: :user }
 
       context 'when user does not have moved to account' do
@@ -32,7 +33,7 @@ describe Settings::MigrationsController do
         end
       end
 
-      context 'when user does not have moved to account' do
+      context 'when user has a moved to account' do
         let(:moved_to_account) { Fabricate(:account) }
 
         it 'renders show page' do
@@ -43,21 +44,22 @@ describe Settings::MigrationsController do
     end
   end
 
-  describe 'PUT #update' do
+  describe 'POST #create' do
     context 'when user is not sign in' do
-      subject { put :update }
+      subject { post :create }
 
       it_behaves_like 'authenticate user'
     end
 
     context 'when user is sign in' do
-      subject { put :update, params: { migration: { acct: acct } } }
+      subject { post :create, params: { account_migration: { acct: acct, current_password: '12345678' } } }
+
+      let(:user) { Fabricate(:user, password: '12345678') }
 
-      let(:user) { Fabricate(:user) }
       before { sign_in user, scope: :user }
 
       context 'when migration account is changed' do
-        let(:acct) { Fabricate(:account) }
+        let(:acct) { Fabricate(:account, also_known_as: [ActivityPub::TagManager.instance.uri_for(user.account)]) }
 
         it 'updates moved to account' do
           is_expected.to redirect_to settings_migration_path

spec/fabricators/account_alias_fabricator.rb

@@ -0,0 +1,5 @@
+Fabricator(:account_alias) do
+  account
+  acct 'test@example.com'
+  uri 'https://example.com/users/test'
+end

spec/fabricators/account_migration_fabricator.rb

@@ -0,0 +1,6 @@
+Fabricator(:account_migration) do
+  account
+  target_account
+  followers_count 1234
+  acct 'test@example.com'
+end

spec/models/account_alias_spec.rb

@@ -0,0 +1,5 @@
+require 'rails_helper'
+
+RSpec.describe AccountAlias, type: :model do
+
+end

spec/models/account_migration_spec.rb

@@ -0,0 +1,5 @@
+require 'rails_helper'
+
+RSpec.describe AccountMigration, type: :model do
+
+end