Profile redirect notes (#5746)

* Serialize moved accounts into REST and ActivityPub APIs

* Parse federated moved accounts from ActivityPub

* Add note about moved accounts to public profiles

* Add moved account message to web UI

* Fix code style issues

18 files changed, 238 insertions, 5 deletions

diff --git a/app/javascript/mastodon/features/account/components/header.js b/app/javascript/mastodon/features/account/components/header.js
index f0d2d481f..b2399ae9b 100644
--- a/app/javascript/mastodon/features/account/components/header.js
+++ b/app/javascript/mastodon/features/account/components/header.js
@@ -7,6 +7,7 @@ import Motion from '../../ui/util/optional_motion';
 import spring from 'react-motion/lib/spring';
 import ImmutablePureComponent from 'react-immutable-pure-component';
 import { autoPlayGif, me } from '../../../initial_state';
+import classNames from 'classnames';
 
 const messages = defineMessages({
   unfollow: { id: 'account.unfollow', defaultMessage: 'Unfollow' },
@@ -102,6 +103,10 @@ export default class Header extends ImmutablePureComponent {
       }
     }
 
+    if (account.get('moved')) {
+      actionBtn = '';
+    }
+
     if (account.get('locked')) {
       lockedIcon = <i className='fa fa-lock' />;
     }
@@ -110,7 +115,7 @@ export default class Header extends ImmutablePureComponent {
     const displayNameHtml = { __html: account.get('display_name_html') };
 
     return (
-      <div className='account__header' style={{ backgroundImage: `url(${account.get('header')})` }}>
+      <div className={classNames('account__header', { inactive: !!account.get('moved') })} style={{ backgroundImage: `url(${account.get('header')})` }}>
         <div>
           <Avatar account={account} />
 
diff --git a/app/javascript/mastodon/features/account_timeline/components/header.js b/app/javascript/mastodon/features/account_timeline/components/header.js
index 8cf7b92ca..5e251c0e5 100644
--- a/app/javascript/mastodon/features/account_timeline/components/header.js
+++ b/app/javascript/mastodon/features/account_timeline/components/header.js
@@ -5,6 +5,7 @@ import InnerHeader from '../../account/components/header';
 import ActionBar from '../../account/components/action_bar';
 import MissingIndicator from '../../../components/missing_indicator';
 import ImmutablePureComponent from 'react-immutable-pure-component';
+import MovedNote from './moved_note';
 
 export default class Header extends ImmutablePureComponent {
 
@@ -68,6 +69,8 @@ export default class Header extends ImmutablePureComponent {
 
     return (
       <div className='account-timeline__header'>
+        {account.get('moved') && <MovedNote from={account} to={account.get('moved')} />}
+
         <InnerHeader
           account={account}
           onFollow={this.handleFollow}
diff --git a/app/javascript/mastodon/features/account_timeline/components/moved_note.js b/app/javascript/mastodon/features/account_timeline/components/moved_note.js
new file mode 100644
index 000000000..1c0e081cc
--- /dev/null
+++ b/app/javascript/mastodon/features/account_timeline/components/moved_note.js
@@ -0,0 +1,48 @@
+import React from 'react';
+import PropTypes from 'prop-types';
+import ImmutablePropTypes from 'react-immutable-proptypes';
+import { FormattedMessage } from 'react-intl';
+import ImmutablePureComponent from 'react-immutable-pure-component';
+import AvatarOverlay from '../../../components/avatar_overlay';
+import DisplayName from '../../../components/display_name';
+
+export default class MovedNote extends ImmutablePureComponent {
+
+  static contextTypes = {
+    router: PropTypes.object,
+  };
+
+  static propTypes = {
+    from: ImmutablePropTypes.map.isRequired,
+    to: ImmutablePropTypes.map.isRequired,
+  };
+
+  handleAccountClick = e => {
+    if (e.button === 0) {
+      e.preventDefault();
+      this.context.router.history.push(`/accounts/${this.props.to.get('id')}`);
+    }
+
+    e.stopPropagation();
+  }
+
+  render () {
+    const { from, to } = this.props;
+    const displayNameHtml = { __html: from.get('display_name_html') };
+
+    return (
+      <div className='account__moved-note'>
+        <div className='account__moved-note__message'>
+          <div className='account__moved-note__icon-wrapper'><i className='fa fa-fw fa-suitcase account__moved-note__icon' /></div>
+          <FormattedMessage id='account.moved_to' defaultMessage='{name} has moved to:' values={{ name: <strong dangerouslySetInnerHTML={displayNameHtml} /> }} />
+        </div>
+
+        <a href={to.get('url')} onClick={this.handleAccountClick} className='detailed-status__display-name'>
+          <div className='detailed-status__display-avatar'><AvatarOverlay account={to} friend={from} /></div>
+          <DisplayName account={to} />
+        </a>
+      </div>
+    );
+  }
+
+}
diff --git a/app/javascript/mastodon/reducers/accounts.js b/app/javascript/mastodon/reducers/accounts.js
index 8a4d69f26..5891d0fdd 100644
--- a/app/javascript/mastodon/reducers/accounts.js
+++ b/app/javascript/mastodon/reducers/accounts.js
@@ -59,6 +59,11 @@ const normalizeAccount = (state, account) => {
   account.display_name_html = emojify(escapeTextContentForBrowser(displayName));
   account.note_emojified = emojify(account.note);
 
+  if (account.moved) {
+    state = normalizeAccount(state, account.moved);
+    account.moved = account.moved.id;
+  }
+
   return state.set(account.id, fromJS(account));
 };
 
diff --git a/app/javascript/mastodon/selectors/index.js b/app/javascript/mastodon/selectors/index.js
index d26d1b727..e47ec5183 100644
--- a/app/javascript/mastodon/selectors/index.js
+++ b/app/javascript/mastodon/selectors/index.js
@@ -4,14 +4,18 @@ import { List as ImmutableList } from 'immutable';
 const getAccountBase         = (state, id) => state.getIn(['accounts', id], null);
 const getAccountCounters     = (state, id) => state.getIn(['accounts_counters', id], null);
 const getAccountRelationship = (state, id) => state.getIn(['relationships', id], null);
+const getAccountMoved        = (state, id) => state.getIn(['accounts', state.getIn(['accounts', id, 'moved'])]);
 
 export const makeGetAccount = () => {
-  return createSelector([getAccountBase, getAccountCounters, getAccountRelationship], (base, counters, relationship) => {
+  return createSelector([getAccountBase, getAccountCounters, getAccountRelationship, getAccountMoved], (base, counters, relationship, moved) => {
     if (base === null) {
       return null;
     }
 
-    return base.merge(counters).set('relationship', relationship);
+    return base.merge(counters).withMutations(map => {
+      map.set('relationship', relationship);
+      map.set('moved', moved);
+    });
   });
 };
 
diff --git a/app/javascript/styles/mastodon/components.scss b/app/javascript/styles/mastodon/components.scss
index 0ded6f159..b70769e18 100644
--- a/app/javascript/styles/mastodon/components.scss
+++ b/app/javascript/styles/mastodon/components.scss
@@ -917,6 +917,18 @@
   background-position: center;
   position: relative;
 
+  &.inactive {
+    opacity: 0.5;
+
+    .account__header__avatar {
+      filter: grayscale(100%);
+    }
+
+    .account__header__username {
+      color: $ui-primary-color;
+    }
+  }
+
   & > div {
     background: rgba(lighten($ui-base-color, 4%), 0.9);
     padding: 20px 10px;
@@ -4375,3 +4387,40 @@ noscript {
     }
   }
 }
+
+.account__moved-note {
+  padding: 14px 10px;
+  padding-bottom: 16px;
+  background: lighten($ui-base-color, 4%);
+  border-top: 1px solid lighten($ui-base-color, 8%);
+  border-bottom: 1px solid lighten($ui-base-color, 8%);
+
+  &__message {
+    position: relative;
+    margin-left: 58px;
+    color: $ui-base-lighter-color;
+    padding: 8px 0;
+    padding-top: 0;
+    padding-bottom: 4px;
+    font-size: 14px;
+
+    > span {
+      display: block;
+      overflow: hidden;
+      text-overflow: ellipsis;
+    }
+  }
+
+  &__icon-wrapper {
+    left: -26px;
+    position: absolute;
+  }
+
+  .detailed-status__display-avatar {
+    position: relative;
+  }
+
+  .detailed-status__display-name {
+    margin-bottom: 0;
+  }
+}
diff --git a/app/javascript/styles/mastodon/landing_strip.scss b/app/javascript/styles/mastodon/landing_strip.scss
index 0bf9daafd..2f7c98d54 100644
--- a/app/javascript/styles/mastodon/landing_strip.scss
+++ b/app/javascript/styles/mastodon/landing_strip.scss
@@ -34,3 +34,66 @@
 .memoriam-strip {
   background: rgba($base-shadow-color, 0.7);
 }
+
+.moved-strip {
+  padding: 14px;
+  border-radius: 4px;
+  background: rgba(darken($ui-base-color, 7%), 0.8);
+  color: $ui-secondary-color;
+  font-weight: 400;
+  margin-bottom: 20px;
+
+  strong,
+  a {
+    font-weight: 500;
+  }
+
+  a {
+    color: inherit;
+    text-decoration: underline;
+
+    &.mention {
+      text-decoration: none;
+
+      span {
+        text-decoration: none;
+      }
+
+      &:focus,
+      &:hover,
+      &:active {
+        text-decoration: none;
+
+        span {
+          text-decoration: underline;
+        }
+      }
+    }
+  }
+
+  &__message {
+    margin-bottom: 15px;
+
+    .fa {
+      margin-right: 5px;
+      color: $ui-primary-color;
+    }
+  }
+
+  &__card {
+    .detailed-status__display-avatar {
+      position: relative;
+      cursor: pointer;
+    }
+
+    .detailed-status__display-name {
+      margin-bottom: 0;
+      text-decoration: none;
+
+      span {
+        color: $ui-highlight-color;
+        font-weight: 400;
+      }
+    }
+  }
+}
diff --git a/app/lib/activitypub/adapter.rb b/app/lib/activitypub/adapter.rb
index 790d2025c..90d589d90 100644
--- a/app/lib/activitypub/adapter.rb
+++ b/app/lib/activitypub/adapter.rb
@@ -9,6 +9,7 @@ class ActivityPub::Adapter < ActiveModelSerializers::Adapter::Base
       {
         'manuallyApprovesFollowers' => 'as:manuallyApprovesFollowers',
         'sensitive'                 => 'as:sensitive',
+        'movedTo'                   => 'as:movedTo',
         'Hashtag'                   => 'as:Hashtag',
         'ostatus'                   => 'http://ostatus.org#',
         'atomUri'                   => 'ostatus:atomUri',
diff --git a/app/models/account.rb b/app/models/account.rb
index 9353c40da..f3f604eda 100644
--- a/app/models/account.rb
+++ b/app/models/account.rb
@@ -42,6 +42,7 @@
 #  followers_url           :string           default(""), not null
 #  protocol                :integer          default("ostatus"), not null
 #  memorial                :boolean          default(FALSE), not null
+#  moved_to_account_id     :integer
 #
 
 class Account < ApplicationRecord
@@ -100,6 +101,9 @@ class Account < ApplicationRecord
   has_many :list_accounts, inverse_of: :account, dependent: :destroy
   has_many :lists, through: :list_accounts
 
+  # Account migrations
+  belongs_to :moved_to_account, class_name: 'Account'
+
   scope :remote, -> { where.not(domain: nil) }
   scope :local, -> { where(domain: nil) }
   scope :without_followers, -> { where(followers_count: 0) }
@@ -133,6 +137,10 @@ class Account < ApplicationRecord
     domain.nil?
   end
 
+  def moved?
+    moved_to_account_id.present?
+  end
+
   def acct
     local? ? username : "#{username}@#{domain}"
   end
diff --git a/app/serializers/activitypub/actor_serializer.rb b/app/serializers/activitypub/actor_serializer.rb
index 896d67115..622bdde0c 100644
--- a/app/serializers/activitypub/actor_serializer.rb
+++ b/app/serializers/activitypub/actor_serializer.rb
@@ -10,6 +10,8 @@ class ActivityPub::ActorSerializer < ActiveModel::Serializer
 
   has_one :public_key, serializer: ActivityPub::PublicKeySerializer
 
+  attribute :moved_to, if: :moved?
+
   class EndpointsSerializer < ActiveModel::Serializer
     include RoutingHelper
 
@@ -25,6 +27,8 @@ class ActivityPub::ActorSerializer < ActiveModel::Serializer
   has_one :icon,  serializer: ActivityPub::ImageSerializer, if: :avatar_exists?
   has_one :image, serializer: ActivityPub::ImageSerializer, if: :header_exists?
 
+  delegate :moved?, to: :object
+
   def id
     account_url(object)
   end
@@ -92,4 +96,8 @@ class ActivityPub::ActorSerializer < ActiveModel::Serializer
   def manually_approves_followers
     object.locked
   end
+
+  def moved_to
+    ActivityPub::TagManager.instance.uri_for(object.moved_to_account)
+  end
 end
diff --git a/app/serializers/rest/account_serializer.rb b/app/serializers/rest/account_serializer.rb
index 65fdb0308..bab944c5a 100644
--- a/app/serializers/rest/account_serializer.rb
+++ b/app/serializers/rest/account_serializer.rb
@@ -7,6 +7,10 @@ class REST::AccountSerializer < ActiveModel::Serializer
              :note, :url, :avatar, :avatar_static, :header, :header_static,
              :followers_count, :following_count, :statuses_count
 
+  has_one :moved_to_account, key: :moved, serializer: REST::AccountSerializer, if: :moved?
+
+  delegate :moved?, to: :object
+
   def id
     object.id.to_s
   end
diff --git a/app/services/activitypub/process_account_service.rb b/app/services/activitypub/process_account_service.rb
index f93baf4b5..5ee7d89ee 100644
--- a/app/services/activitypub/process_account_service.rb
+++ b/app/services/activitypub/process_account_service.rb
@@ -74,6 +74,7 @@ class ActivityPub::ProcessAccountService < BaseService
     @account.statuses_count    = outbox_total_items    if outbox_total_items.present?
     @account.following_count   = following_total_items if following_total_items.present?
     @account.followers_count   = followers_total_items if followers_total_items.present?
+    @account.moved_to_account  = moved_account         if @json['movedTo'].present?
   end
 
   def after_protocol_change!
@@ -137,6 +138,12 @@ class ActivityPub::ProcessAccountService < BaseService
     @collections[type] = nil
   end
 
+  def moved_account
+    account   = ActivityPub::TagManager.instance.uri_to_resource(@json['movedTo'], Account)
+    account ||= ActivityPub::FetchRemoteAccountService.new.call(@json['movedTo'], id: true)
+    account
+  end
+
   def skip_download?
     @account.suspended? || domain_block&.reject_media?
   end
diff --git a/app/views/accounts/_header.html.haml b/app/views/accounts/_header.html.haml
index e4c258acd..76371b656 100644
--- a/app/views/accounts/_header.html.haml
+++ b/app/views/accounts/_header.html.haml
@@ -1,6 +1,6 @@
 .card.h-card.p-author{ style: "background-image: url(#{account.header.url(:original)})" }
   .card__illustration
-    - unless account.memorial?
+    - unless account.memorial? || account.moved?
       - if user_signed_in? && current_account.id != account.id && !current_account.requested?(account)
         .controls
           - if current_account.following?(account)
diff --git a/app/views/accounts/_moved_strip.html.haml b/app/views/accounts/_moved_strip.html.haml
new file mode 100644
index 000000000..6a14a5dd3
--- /dev/null
+++ b/app/views/accounts/_moved_strip.html.haml
@@ -0,0 +1,17 @@
+- moved_to_account = account.moved_to_account
+
+.moved-strip
+  .moved-strip__message
+    = fa_icon 'suitcase'
+    = t('accounts.moved_html', name: content_tag(:strong, display_name(account), class: :emojify), new_profile_link: link_to(content_tag(:strong, safe_join(['@', content_tag(:span, moved_to_account.acct)])), TagManager.instance.url_for(moved_to_account), class: 'mention'))
+
+  .moved-strip__card
+    = link_to TagManager.instance.url_for(moved_to_account), class: 'detailed-status__display-name p-author h-card', target: '_blank', rel: 'noopener' do
+      .detailed-status__display-avatar
+        .account__avatar-overlay
+          .account__avatar-overlay-base{ style: "background-image: url('#{moved_to_account.avatar.url(:original)}')" }
+          .account__avatar-overlay-overlay{ style: "background-image: url('#{account.avatar.url(:original)}')" }
+
+      %span.display-name
+        %strong.emojify= display_name(moved_to_account)
+        %span @#{moved_to_account.acct}
diff --git a/app/views/accounts/show.html.haml b/app/views/accounts/show.html.haml
index fd8ad5530..accad5f78 100644
--- a/app/views/accounts/show.html.haml
+++ b/app/views/accounts/show.html.haml
@@ -14,6 +14,8 @@
 
 - if @account.memorial?
   .memoriam-strip= t('in_memoriam_html')
+- elsif @account.moved?
+  = render partial: 'moved_strip', locals: { account: @account }
 - elsif show_landing_strip?
   = render partial: 'shared/landing_strip', locals: { account: @account }
 
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 11c34b912..cef001341 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -39,6 +39,7 @@ en:
     followers: Followers
     following: Following
     media: Media
+    moved_html: "%{name} has moved to %{new_profile_link}:"
     nothing_here: There is nothing here!
     people_followed_by: People whom %{name} follows
     people_who_follow: People who follow %{name}
diff --git a/db/migrate/20171118012443_add_moved_to_account_id_to_accounts.rb b/db/migrate/20171118012443_add_moved_to_account_id_to_accounts.rb
new file mode 100644
index 000000000..0c8a894cc
--- /dev/null
+++ b/db/migrate/20171118012443_add_moved_to_account_id_to_accounts.rb
@@ -0,0 +1,6 @@
+class AddMovedToAccountIdToAccounts < ActiveRecord::Migration[5.1]
+  def change
+    add_column :accounts, :moved_to_account_id, :bigint, null: true, default: nil
+    add_foreign_key :accounts, :accounts, column: :moved_to_account_id, on_delete: :nullify
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 345b05850..16df5d7c9 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20171116161857) do
+ActiveRecord::Schema.define(version: 20171118012443) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -72,6 +72,7 @@ ActiveRecord::Schema.define(version: 20171116161857) do
     t.string "followers_url", default: "", null: false
     t.integer "protocol", default: 0, null: false
     t.boolean "memorial", default: false, null: false
+    t.bigint "moved_to_account_id"
     t.index "(((setweight(to_tsvector('simple'::regconfig, (display_name)::text), 'A'::\"char\") || setweight(to_tsvector('simple'::regconfig, (username)::text), 'B'::\"char\")) || setweight(to_tsvector('simple'::regconfig, (COALESCE(domain, ''::character varying))::text), 'C'::\"char\")))", name: "search_index", using: :gin
     t.index "lower((username)::text), lower((domain)::text)", name: "index_accounts_on_username_and_domain_lower"
     t.index ["uri"], name: "index_accounts_on_uri"
@@ -486,6 +487,7 @@ ActiveRecord::Schema.define(version: 20171116161857) do
   add_foreign_key "account_domain_blocks", "accounts", name: "fk_206c6029bd", on_delete: :cascade
   add_foreign_key "account_moderation_notes", "accounts"
   add_foreign_key "account_moderation_notes", "accounts", column: "target_account_id"
+  add_foreign_key "accounts", "accounts", column: "moved_to_account_id", on_delete: :nullify
   add_foreign_key "blocks", "accounts", column: "target_account_id", name: "fk_9571bfabc1", on_delete: :cascade
   add_foreign_key "blocks", "accounts", name: "fk_4269e03e65", on_delete: :cascade
   add_foreign_key "conversation_mutes", "accounts", name: "fk_225b4212bb", on_delete: :cascade