Lazy load components (#3879)

* feat: Lazy-load routes

* feat: Lazy-load modals

* feat: Lazy-load columns

* refactor: Simplify Bundle API

* feat: Optimize bundles

* feat: Prevent flashing the waiting state

* feat: Preload commonly used bundles

* feat: Lazy load Compose reducers

* feat: Lazy load Notifications reducer

* refactor: Move all dynamic imports into one file

* fix: Minor bugs

* fix: Manually hydrate the lazy-loaded reducers

* refactor: Move all dynamic imports to async-components

* fix: Loading modal style

* refactor: Avoid converting the raw state for each lazy hydration

* refactor: Remove unused component

* refactor: Maintain modal name

* fix: Add as=script to preload link

* chore: Fix lint error

* fix(components/bundle): Check if timestamp is set when computing elapsed

* fix: Load compose reducers for the onboarding modal

1 files changed, 53 insertions, 0 deletions

diff --git a/app/javascript/mastodon/features/ui/components/bundle_modal_error.js b/app/javascript/mastodon/features/ui/components/bundle_modal_error.js
new file mode 100644
index 000000000..928bfe1f7
--- /dev/null
+++ b/app/javascript/mastodon/features/ui/components/bundle_modal_error.js
@@ -0,0 +1,53 @@
+import React from 'react';
+import PropTypes from 'prop-types';
+import { defineMessages, injectIntl } from 'react-intl';
+
+import IconButton from '../../../components/icon_button';
+
+const messages = defineMessages({
+  error: { id: 'bundle_modal_error.message', defaultMessage: 'Something went wrong while loading this component.' },
+  retry: { id: 'bundle_modal_error.retry', defaultMessage: 'Try again' },
+  close: { id: 'bundle_modal_error.close', defaultMessage: 'Close' },
+});
+
+class BundleModalError extends React.Component {
+
+  static propTypes = {
+    onRetry: PropTypes.func.isRequired,
+    onClose: PropTypes.func.isRequired,
+    intl: PropTypes.object.isRequired,
+  }
+
+  handleRetry = () => {
+    this.props.onRetry();
+  }
+
+  render () {
+    const { onClose, intl: { formatMessage } } = this.props;
+
+    // Keep the markup in sync with <ModalLoading />
+    // (make sure they have the same dimensions)
+    return (
+      <div className='modal-root__modal error-modal'>
+        <div className='error-modal__body'>
+          <IconButton title={formatMessage(messages.retry)} icon='refresh' onClick={this.handleRetry} size={64} />
+          {formatMessage(messages.error)}
+        </div>
+
+        <div className='error-modal__footer'>
+          <div>
+            <button
+              onClick={onClose}
+              className='error-modal__nav onboarding-modal__skip'
+            >
+              {formatMessage(messages.close)}
+            </button>
+          </div>
+        </div>
+      </div>
+    );
+  }
+
+}
+
+export default injectIntl(BundleModalError);