catstodon/app/javascript/mastodon/containers/status_container.js
Matt Panaro 31f7c3fc5d Summary: fix slowness due to layout thrashing when reloading a large … (#12661)
* Summary: fix slowness due to layout thrashing when reloading a large set of status updates

in order to limit the maximum size of a status in a list view (e.g. the home timeline), so as to avoid having to scroll all the way through an abnormally large status update (see https://github.com/tootsuite/mastodon/pull/8205), the following steps are taken:
•the element containing the status is rendered in the browser
•its height is calculated, to determine if it exceeds the maximum height threshold.
Unfortunately for performance, these steps are carried out in the componentDidMount(/Update) method, which also performs style modifications on the element.  The combination of  height request and style modification during javascript evaluation in the browser leads to layout-thrashing, where the elements are repeatedly re-laid-out (see https://developers.google.com/web/fundamentals/performance/rendering/avoid-large-complex-layouts-and-layout-thrashing & https://developer.mozilla.org/en-US/docs/Mozilla/Firefox/Performance_best_practices_for_Firefox_fe_engineers).
The solution implemented here is to memoize the collapsed state in Redux the first time the status is seen (e.g. when fetched as part of a small batch, to populate the home timeline) , so that on subsequent re-renders, the value can be queried, rather than recalculated.  This strategy is derived from https://github.com/tootsuite/mastodon/pull/4439 & https://github.com/tootsuite/mastodon/pull/4909, and should resolve https://github.com/tootsuite/mastodon/issues/12455.

Andrew Lin (https://github.com/onethreeseven) is thanked for his assistance in root cause analysis and solution brainstorming

* remove getSnapshotBeforeUpdate from status

* remove componentWillUnmount from status

* persist last-intersected status update and restore when ScrollableList is restored

e.g. when navigating from home-timeline to a status conversational  thread and <Back again

* cache currently-viewing status id to avoid calling redux with identical value

* refactor collapse toggle to pass explicit boolean
2019-12-29 05:39:48 +01:00

212 lines
6.1 KiB
JavaScript

import React from 'react';
import { connect } from 'react-redux';
import Status from '../components/status';
import { makeGetStatus } from '../selectors';
import {
replyCompose,
mentionCompose,
directCompose,
} from '../actions/compose';
import {
reblog,
favourite,
bookmark,
unreblog,
unfavourite,
unbookmark,
pin,
unpin,
} from '../actions/interactions';
import {
muteStatus,
unmuteStatus,
deleteStatus,
hideStatus,
revealStatus,
toggleStatusCollapse,
} from '../actions/statuses';
import {
unmuteAccount,
unblockAccount,
} from '../actions/accounts';
import {
blockDomain,
unblockDomain,
} from '../actions/domain_blocks';
import { initMuteModal } from '../actions/mutes';
import { initBlockModal } from '../actions/blocks';
import { initReport } from '../actions/reports';
import { openModal } from '../actions/modal';
import { defineMessages, injectIntl, FormattedMessage } from 'react-intl';
import { boostModal, deleteModal } from '../initial_state';
import { showAlertForError } from '../actions/alerts';
const messages = defineMessages({
deleteConfirm: { id: 'confirmations.delete.confirm', defaultMessage: 'Delete' },
deleteMessage: { id: 'confirmations.delete.message', defaultMessage: 'Are you sure you want to delete this status?' },
redraftConfirm: { id: 'confirmations.redraft.confirm', defaultMessage: 'Delete & redraft' },
redraftMessage: { id: 'confirmations.redraft.message', defaultMessage: 'Are you sure you want to delete this status and re-draft it? Favourites and boosts will be lost, and replies to the original post will be orphaned.' },
replyConfirm: { id: 'confirmations.reply.confirm', defaultMessage: 'Reply' },
replyMessage: { id: 'confirmations.reply.message', defaultMessage: 'Replying now will overwrite the message you are currently composing. Are you sure you want to proceed?' },
blockDomainConfirm: { id: 'confirmations.domain_block.confirm', defaultMessage: 'Hide entire domain' },
});
const makeMapStateToProps = () => {
const getStatus = makeGetStatus();
const mapStateToProps = (state, props) => ({
status: getStatus(state, props),
});
return mapStateToProps;
};
const mapDispatchToProps = (dispatch, { intl }) => ({
onReply (status, router) {
dispatch((_, getState) => {
let state = getState();
if (state.getIn(['compose', 'text']).trim().length !== 0) {
dispatch(openModal('CONFIRM', {
message: intl.formatMessage(messages.replyMessage),
confirm: intl.formatMessage(messages.replyConfirm),
onConfirm: () => dispatch(replyCompose(status, router)),
}));
} else {
dispatch(replyCompose(status, router));
}
});
},
onModalReblog (status) {
if (status.get('reblogged')) {
dispatch(unreblog(status));
} else {
dispatch(reblog(status));
}
},
onReblog (status, e) {
if ((e && e.shiftKey) || !boostModal) {
this.onModalReblog(status);
} else {
dispatch(openModal('BOOST', { status, onReblog: this.onModalReblog }));
}
},
onFavourite (status) {
if (status.get('favourited')) {
dispatch(unfavourite(status));
} else {
dispatch(favourite(status));
}
},
onBookmark (status) {
if (status.get('bookmarked')) {
dispatch(unbookmark(status));
} else {
dispatch(bookmark(status));
}
},
onPin (status) {
if (status.get('pinned')) {
dispatch(unpin(status));
} else {
dispatch(pin(status));
}
},
onEmbed (status) {
dispatch(openModal('EMBED', {
url: status.get('url'),
onError: error => dispatch(showAlertForError(error)),
}));
},
onDelete (status, history, withRedraft = false) {
if (!deleteModal) {
dispatch(deleteStatus(status.get('id'), history, withRedraft));
} else {
dispatch(openModal('CONFIRM', {
message: intl.formatMessage(withRedraft ? messages.redraftMessage : messages.deleteMessage),
confirm: intl.formatMessage(withRedraft ? messages.redraftConfirm : messages.deleteConfirm),
onConfirm: () => dispatch(deleteStatus(status.get('id'), history, withRedraft)),
}));
}
},
onDirect (account, router) {
dispatch(directCompose(account, router));
},
onMention (account, router) {
dispatch(mentionCompose(account, router));
},
onOpenMedia (media, index) {
dispatch(openModal('MEDIA', { media, index }));
},
onOpenVideo (media, time) {
dispatch(openModal('VIDEO', { media, time }));
},
onBlock (status) {
const account = status.get('account');
dispatch(initBlockModal(account));
},
onUnblock (account) {
dispatch(unblockAccount(account.get('id')));
},
onReport (status) {
dispatch(initReport(status.get('account'), status));
},
onMute (account) {
dispatch(initMuteModal(account));
},
onUnmute (account) {
dispatch(unmuteAccount(account.get('id')));
},
onMuteConversation (status) {
if (status.get('muted')) {
dispatch(unmuteStatus(status.get('id')));
} else {
dispatch(muteStatus(status.get('id')));
}
},
onToggleHidden (status) {
if (status.get('hidden')) {
dispatch(revealStatus(status.get('id')));
} else {
dispatch(hideStatus(status.get('id')));
}
},
onToggleCollapsed (status, isCollapsed) {
dispatch(toggleStatusCollapse(status.get('id'), isCollapsed));
},
onBlockDomain (domain) {
dispatch(openModal('CONFIRM', {
message: <FormattedMessage id='confirmations.domain_block.message' defaultMessage='Are you really, really sure you want to block the entire {domain}? In most cases a few targeted blocks or mutes are sufficient and preferable. You will not see content from that domain in any public timelines or your notifications. Your followers from that domain will be removed.' values={{ domain: <strong>{domain}</strong> }} />,
confirm: intl.formatMessage(messages.blockDomainConfirm),
onConfirm: () => dispatch(blockDomain(domain)),
}));
},
onUnblockDomain (domain) {
dispatch(unblockDomain(domain));
},
});
export default injectIntl(connect(makeMapStateToProps, mapDispatchToProps)(Status));