Add listing of followed hashtags (#21773)

* Add followed_tags route.

This at least gets us to the point where the page can actually be
rendered, although it doesn't display any hashtags (yet?).

Attempting to implement #20763.

* Fix minor issues.

* I've got the followed tags data partially working

But the Hashtag component errors for some reason. Something about the
value of the history attribute being invalid.

* Fix a mistake in the code

* Minor change.

* Get the followed hashtags list fully working.

Still need to add the Follow/Unfollow buttons, though.

* Resolve JS linter issues.

* Add pagination logic to followed tags list view.

However, it currently loads further pages immediately on page load, so
that's not ideal. Need to figure that one out.

* Appease the linter.

* Apply suggestions from code review

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

* Fixes and resolve some other feedback.

* Use set/update instead of setIn/updateIn.

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

11 files changed, 231 insertions, 2 deletions

diff --git a/app/javascript/mastodon/actions/tags.js b/app/javascript/mastodon/actions/tags.js
index 37e79d4cb..08a08cda3 100644
--- a/app/javascript/mastodon/actions/tags.js
+++ b/app/javascript/mastodon/actions/tags.js
@@ -1,9 +1,17 @@
-import api from '../api';
+import api, { getLinks } from '../api';
 
 export const HASHTAG_FETCH_REQUEST = 'HASHTAG_FETCH_REQUEST';
 export const HASHTAG_FETCH_SUCCESS = 'HASHTAG_FETCH_SUCCESS';
 export const HASHTAG_FETCH_FAIL    = 'HASHTAG_FETCH_FAIL';
 
+export const FOLLOWED_HASHTAGS_FETCH_REQUEST = 'FOLLOWED_HASHTAGS_FETCH_REQUEST';
+export const FOLLOWED_HASHTAGS_FETCH_SUCCESS = 'FOLLOWED_HASHTAGS_FETCH_SUCCESS';
+export const FOLLOWED_HASHTAGS_FETCH_FAIL    = 'FOLLOWED_HASHTAGS_FETCH_FAIL';
+
+export const FOLLOWED_HASHTAGS_EXPAND_REQUEST = 'FOLLOWED_HASHTAGS_EXPAND_REQUEST';
+export const FOLLOWED_HASHTAGS_EXPAND_SUCCESS = 'FOLLOWED_HASHTAGS_EXPAND_SUCCESS';
+export const FOLLOWED_HASHTAGS_EXPAND_FAIL    = 'FOLLOWED_HASHTAGS_EXPAND_FAIL';
+
 export const HASHTAG_FOLLOW_REQUEST = 'HASHTAG_FOLLOW_REQUEST';
 export const HASHTAG_FOLLOW_SUCCESS = 'HASHTAG_FOLLOW_SUCCESS';
 export const HASHTAG_FOLLOW_FAIL    = 'HASHTAG_FOLLOW_FAIL';
@@ -37,6 +45,78 @@ export const fetchHashtagFail = error => ({
   error,
 });
 
+export const fetchFollowedHashtags = () => (dispatch, getState) => {
+  dispatch(fetchFollowedHashtagsRequest());
+
+  api(getState).get('/api/v1/followed_tags').then(response => {
+    const next = getLinks(response).refs.find(link => link.rel === 'next');
+    dispatch(fetchFollowedHashtagsSuccess(response.data, next ? next.uri : null));
+  }).catch(err => {
+    dispatch(fetchFollowedHashtagsFail(err));
+  });
+};
+
+export function fetchFollowedHashtagsRequest() {
+  return {
+    type: FOLLOWED_HASHTAGS_FETCH_REQUEST,
+  };
+};
+
+export function fetchFollowedHashtagsSuccess(followed_tags, next) {
+  return {
+    type: FOLLOWED_HASHTAGS_FETCH_SUCCESS,
+    followed_tags,
+    next,
+  };
+};
+
+export function fetchFollowedHashtagsFail(error) {
+  return {
+    type: FOLLOWED_HASHTAGS_FETCH_FAIL,
+    error,
+  };
+};
+
+export function expandFollowedHashtags() {
+  return (dispatch, getState) => {
+    const url = getState().getIn(['followed_tags', 'next']);
+
+    if (url === null) {
+      return;
+    }
+
+    dispatch(expandFollowedHashtagsRequest());
+
+    api(getState).get(url).then(response => {
+      const next = getLinks(response).refs.find(link => link.rel === 'next');
+      dispatch(expandFollowedHashtagsSuccess(response.data, next ? next.uri : null));
+    }).catch(error => {
+      dispatch(expandFollowedHashtagsFail(error));
+    });
+  };
+};
+
+export function expandFollowedHashtagsRequest() {
+  return {
+    type: FOLLOWED_HASHTAGS_EXPAND_REQUEST,
+  };
+};
+
+export function expandFollowedHashtagsSuccess(followed_tags, next) {
+  return {
+    type: FOLLOWED_HASHTAGS_EXPAND_SUCCESS,
+    followed_tags,
+    next,
+  };
+};
+
+export function expandFollowedHashtagsFail(error) {
+  return {
+    type: FOLLOWED_HASHTAGS_EXPAND_FAIL,
+    error,
+  };
+};
+
 export const followHashtag = name => (dispatch, getState) => {
   dispatch(followHashtagRequest(name));
 
diff --git a/app/javascript/mastodon/features/account/components/header.js b/app/javascript/mastodon/features/account/components/header.js
index f6004d1c4..46fb89f2f 100644
--- a/app/javascript/mastodon/features/account/components/header.js
+++ b/app/javascript/mastodon/features/account/components/header.js
@@ -46,6 +46,7 @@ const messages = defineMessages({
   follow_requests: { id: 'navigation_bar.follow_requests', defaultMessage: 'Follow requests' },
   favourites: { id: 'navigation_bar.favourites', defaultMessage: 'Favourites' },
   lists: { id: 'navigation_bar.lists', defaultMessage: 'Lists' },
+  followed_tags: { id: 'navigation_bar.followed_tags', defaultMessage: 'Followed hashtags' },
   blocks: { id: 'navigation_bar.blocks', defaultMessage: 'Blocked users' },
   domain_blocks: { id: 'navigation_bar.domain_blocks', defaultMessage: 'Blocked domains' },
   mutes: { id: 'navigation_bar.mutes', defaultMessage: 'Muted users' },
@@ -242,6 +243,7 @@ class Header extends ImmutablePureComponent {
       menu.push({ text: intl.formatMessage(messages.follow_requests), to: '/follow_requests' });
       menu.push({ text: intl.formatMessage(messages.favourites), to: '/favourites' });
       menu.push({ text: intl.formatMessage(messages.lists), to: '/lists' });
+      menu.push({ text: intl.formatMessage(messages.followed_tags), to: '/followed_tags' });
       menu.push(null);
       menu.push({ text: intl.formatMessage(messages.mutes), to: '/mutes' });
       menu.push({ text: intl.formatMessage(messages.blocks), to: '/blocks' });
diff --git a/app/javascript/mastodon/features/compose/components/action_bar.js b/app/javascript/mastodon/features/compose/components/action_bar.js
index ceed928bf..90c85321e 100644
--- a/app/javascript/mastodon/features/compose/components/action_bar.js
+++ b/app/javascript/mastodon/features/compose/components/action_bar.js
@@ -11,6 +11,7 @@ const messages = defineMessages({
   follow_requests: { id: 'navigation_bar.follow_requests', defaultMessage: 'Follow requests' },
   favourites: { id: 'navigation_bar.favourites', defaultMessage: 'Favourites' },
   lists: { id: 'navigation_bar.lists', defaultMessage: 'Lists' },
+  followed_tags: { id: 'navigation_bar.followed_tags', defaultMessage: 'Followed hashtags' },
   blocks: { id: 'navigation_bar.blocks', defaultMessage: 'Blocked users' },
   domain_blocks: { id: 'navigation_bar.domain_blocks', defaultMessage: 'Hidden domains' },
   mutes: { id: 'navigation_bar.mutes', defaultMessage: 'Muted users' },
@@ -45,6 +46,7 @@ class ActionBar extends React.PureComponent {
     menu.push({ text: intl.formatMessage(messages.favourites), to: '/favourites' });
     menu.push({ text: intl.formatMessage(messages.bookmarks), to: '/bookmarks' });
     menu.push({ text: intl.formatMessage(messages.lists), to: '/lists' });
+    menu.push({ text: intl.formatMessage(messages.followed_tags), to: '/followed_tags' });
     menu.push(null);
     menu.push({ text: intl.formatMessage(messages.mutes), to: '/mutes' });
     menu.push({ text: intl.formatMessage(messages.blocks), to: '/blocks' });
diff --git a/app/javascript/mastodon/features/followed_tags/index.js b/app/javascript/mastodon/features/followed_tags/index.js
new file mode 100644
index 000000000..0a62ca76d
--- /dev/null
+++ b/app/javascript/mastodon/features/followed_tags/index.js
@@ -0,0 +1,89 @@
+import { debounce } from 'lodash';
+import PropTypes from 'prop-types';
+import React from 'react';
+import ImmutablePureComponent from 'react-immutable-pure-component';
+import ImmutablePropTypes from 'react-immutable-proptypes';
+import { defineMessages, injectIntl, FormattedMessage } from 'react-intl';
+import { connect } from 'react-redux';
+import ColumnHeader from 'mastodon/components/column_header';
+import ScrollableList from 'mastodon/components/scrollable_list';
+import Column from 'mastodon/features/ui/components/column';
+import { Helmet } from 'react-helmet';
+import Hashtag from 'mastodon/components/hashtag';
+import { expandFollowedHashtags, fetchFollowedHashtags } from 'mastodon/actions/tags';
+
+const messages = defineMessages({
+  heading: { id: 'followed_tags', defaultMessage: 'Followed hashtags' },
+});
+
+const mapStateToProps = state => ({
+  hashtags: state.getIn(['followed_tags', 'items']),
+  isLoading: state.getIn(['followed_tags', 'isLoading'], true),
+  hasMore: !!state.getIn(['followed_tags', 'next']),
+});
+
+export default @connect(mapStateToProps)
+@injectIntl
+class FollowedTags extends ImmutablePureComponent {
+
+  static propTypes = {
+    params: PropTypes.object.isRequired,
+    dispatch: PropTypes.func.isRequired,
+    intl: PropTypes.object.isRequired,
+    hashtags: ImmutablePropTypes.list,
+    isLoading: PropTypes.bool,
+    hasMore: PropTypes.bool,
+    multiColumn: PropTypes.bool,
+  };
+
+  componentDidMount() {
+    this.props.dispatch(fetchFollowedHashtags());
+  };
+
+  handleLoadMore = debounce(() => {
+    this.props.dispatch(expandFollowedHashtags());
+  }, 300, { leading: true });
+
+  render () {
+    const { intl, hashtags, isLoading, hasMore, multiColumn } = this.props;
+
+    const emptyMessage = <FormattedMessage id='empty_column.followed_tags' defaultMessage='You have not followed any hashtags yet. When you do, they will show up here.' />;
+
+    return (
+      <Column bindToDocument={!multiColumn}>
+        <ColumnHeader
+          icon='hashtag'
+          title={intl.formatMessage(messages.heading)}
+          showBackButton
+          multiColumn={multiColumn}
+        />
+
+        <ScrollableList
+          scrollKey='followed_tags'
+          emptyMessage={emptyMessage}
+          hasMore={hasMore}
+          isLoading={isLoading}
+          onLoadMore={this.handleLoadMore}
+          bindToDocument={!multiColumn}
+        >
+          {hashtags.map((hashtag) => (
+            <Hashtag
+              key={hashtag.get('name')}
+              name={hashtag.get('name')}
+              to={`/tags/${hashtag.get('name')}`}
+              withGraph={false}
+              // Taken from ImmutableHashtag. Should maybe refactor ImmutableHashtag to accept more options?
+              people={hashtag.getIn(['history', 0, 'accounts']) * 1 + hashtag.getIn(['history', 1, 'accounts']) * 1}
+              history={hashtag.get('history').reverse().map((day) => day.get('uses')).toArray()}
+            />
+          ))}
+        </ScrollableList>
+
+        <Helmet>
+          <meta name='robots' content='noindex' />
+        </Helmet>
+      </Column>
+    );
+  }
+
+}
diff --git a/app/javascript/mastodon/features/ui/index.js b/app/javascript/mastodon/features/ui/index.js
index 3fbe03fdf..78dc9ea40 100644
--- a/app/javascript/mastodon/features/ui/index.js
+++ b/app/javascript/mastodon/features/ui/index.js
@@ -42,6 +42,7 @@ import {
   FollowRequests,
   FavouritedStatuses,
   BookmarkedStatuses,
+  FollowedTags,
   ListTimeline,
   Blocks,
   DomainBlocks,
@@ -216,6 +217,7 @@ class SwitchingColumnsArea extends React.PureComponent {
           <WrappedRoute path='/follow_requests' component={FollowRequests} content={children} />
           <WrappedRoute path='/blocks' component={Blocks} content={children} />
           <WrappedRoute path='/domain_blocks' component={DomainBlocks} content={children} />
+          <WrappedRoute path='/followed_tags' component={FollowedTags} content={children} />
           <WrappedRoute path='/mutes' component={Mutes} content={children} />
           <WrappedRoute path='/lists' component={Lists} content={children} />
 
diff --git a/app/javascript/mastodon/features/ui/util/async-components.js b/app/javascript/mastodon/features/ui/util/async-components.js
index 6046578de..1cf07f645 100644
--- a/app/javascript/mastodon/features/ui/util/async-components.js
+++ b/app/javascript/mastodon/features/ui/util/async-components.js
@@ -90,6 +90,10 @@ export function FavouritedStatuses () {
   return import(/* webpackChunkName: "features/favourited_statuses" */'../../favourited_statuses');
 }
 
+export function FollowedTags () {
+  return import(/* webpackChunkName: "features/followed_tags" */'../../followed_tags');
+}
+
 export function BookmarkedStatuses () {
   return import(/* webpackChunkName: "features/bookmarked_statuses" */'../../bookmarked_statuses');
 }
diff --git a/app/javascript/mastodon/locales/defaultMessages.json b/app/javascript/mastodon/locales/defaultMessages.json
index 3ed438fb8..210c91ad4 100644
--- a/app/javascript/mastodon/locales/defaultMessages.json
+++ b/app/javascript/mastodon/locales/defaultMessages.json
@@ -1392,6 +1392,10 @@
         "id": "navigation_bar.lists"
       },
       {
+        "defaultMessage": "Followed hashtags",
+        "id": "navigation_bar.followed_tags"
+      },
+      {
         "defaultMessage": "Blocked users",
         "id": "navigation_bar.blocks"
       },
@@ -4310,4 +4314,4 @@
     ],
     "path": "app/javascript/mastodon/features/video/index.json"
   }
-]
\ No newline at end of file
+]
diff --git a/app/javascript/mastodon/locales/en.json b/app/javascript/mastodon/locales/en.json
index 0240bf2e6..992996dfb 100644
--- a/app/javascript/mastodon/locales/en.json
+++ b/app/javascript/mastodon/locales/en.json
@@ -379,6 +379,7 @@
   "navigation_bar.favourites": "Favourites",
   "navigation_bar.filters": "Muted words",
   "navigation_bar.follow_requests": "Follow requests",
+  "navigation_bar.followed_tags": "Followed hashtags",
   "navigation_bar.follows_and_followers": "Follows and followers",
   "navigation_bar.lists": "Lists",
   "navigation_bar.logout": "Logout",
diff --git a/app/javascript/mastodon/reducers/followed_tags.js b/app/javascript/mastodon/reducers/followed_tags.js
new file mode 100644
index 000000000..f50ee6aa3
--- /dev/null
+++ b/app/javascript/mastodon/reducers/followed_tags.js
@@ -0,0 +1,42 @@
+import {
+  FOLLOWED_HASHTAGS_FETCH_REQUEST,
+  FOLLOWED_HASHTAGS_FETCH_SUCCESS,
+  FOLLOWED_HASHTAGS_FETCH_FAIL,
+  FOLLOWED_HASHTAGS_EXPAND_REQUEST,
+  FOLLOWED_HASHTAGS_EXPAND_SUCCESS,
+  FOLLOWED_HASHTAGS_EXPAND_FAIL,
+} from 'mastodon/actions/tags';
+import { Map as ImmutableMap, List as ImmutableList, fromJS } from 'immutable';
+
+const initialState = ImmutableMap({
+  items: ImmutableList(),
+  isLoading: false,
+  next: null,
+});
+
+export default function followed_tags(state = initialState, action) {
+  switch(action.type) {
+  case FOLLOWED_HASHTAGS_FETCH_REQUEST:
+    return state.set('isLoading', true);
+  case FOLLOWED_HASHTAGS_FETCH_SUCCESS:
+    return state.withMutations(map => {
+      map.set('items', fromJS(action.followed_tags));
+      map.set('isLoading', false);
+      map.set('next', action.next);
+    });
+  case FOLLOWED_HASHTAGS_FETCH_FAIL:
+    return state.set('isLoading', false);
+  case FOLLOWED_HASHTAGS_EXPAND_REQUEST:
+    return state.set('isLoading', true);
+  case FOLLOWED_HASHTAGS_EXPAND_SUCCESS:
+    return state.withMutations(map => {
+      map.update('items', set => set.concat(fromJS(action.followed_tags)));
+      map.set('isLoading', false);
+      map.set('next', action.next);
+    });
+  case FOLLOWED_HASHTAGS_EXPAND_FAIL:
+    return state.set('isLoading', false);
+  default:
+    return state;
+  }
+};
diff --git a/app/javascript/mastodon/reducers/index.js b/app/javascript/mastodon/reducers/index.js
index bccdc1865..69771ad1b 100644
--- a/app/javascript/mastodon/reducers/index.js
+++ b/app/javascript/mastodon/reducers/index.js
@@ -40,6 +40,7 @@ import picture_in_picture from './picture_in_picture';
 import accounts_map from './accounts_map';
 import history from './history';
 import tags from './tags';
+import followed_tags from './followed_tags';
 
 const reducers = {
   announcements,
@@ -83,6 +84,7 @@ const reducers = {
   picture_in_picture,
   history,
   tags,
+  followed_tags,
 };
 
 export default combineReducers(reducers);
diff --git a/config/routes.rb b/config/routes.rb
index 0bee2f639..319f0c7d1 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -27,6 +27,7 @@ Rails.application.routes.draw do
     /blocks
     /domain_blocks
     /mutes
+    /followed_tags
     /statuses/(*any)
   ).freeze