fix(live-streaming): show warning if stream key seems wrong

Provide a client-side notice if the YouTube live stream key
looks like it might be in the wrong format. Normally the
stream key looks like 4 groups of 4 numbers and letters,
each separated by a dash. The warning does not block submission
in case YouTube changes their stream key format.

css/_recording.scss

@@ -65,6 +65,8 @@
     }
 
     .form-footer {
+        display: flex;
+        margin-top: 5px;
         text-align: right;
     }
 
@@ -95,9 +97,15 @@
 
     .stream-key-form {
         .helper-link {
-            display: inline-block;
             cursor: pointer;
-            margin-top: 5px;
+            display: inline-block;
+            flex-shrink: 0;
+            margin-left: auto;
+        }
+
+        .validation-error {
+            color:#FFD740;
+            font-size: 12px;
         }
     }
 }

lang/main.json

@@ -515,6 +515,7 @@
         "expandedOn": "The meeting is currently being streamed to YouTube.",
         "expandedPending": "The live streaming is being started...",
         "failedToStart": "Live Streaming failed to start",
+        "invalidStreamKey": "Live stream key may be incorrect.",
         "off": "Live Streaming stopped",
         "on": "Live Streaming",
         "pending": "Starting Live Stream...",

react/features/recording/components/LiveStream/AbstractStreamKeyForm.js

@@ -1,5 +1,6 @@
 // @flow
 
+import debounce from 'lodash/debounce';
 import { Component } from 'react';
 
 declare var interfaceConfig: Object;
@@ -33,14 +34,27 @@ export type Props = {
     value: string
 };
 
+/**
+ * The state of the component.
+ */
+type State = {
+
+    /**
+     * Whether or not to show the warnings that the passed in value seems like
+     * an improperly formatted stream key.
+     */
+    showValidationError: boolean
+};
+
 /**
  * An abstract React Component for entering a key for starting a YouTube live
  * stream.
  *
  * @extends Component
  */
-export default class AbstractStreamKeyForm extends Component<Props> {
+export default class AbstractStreamKeyForm extends Component<Props, State> {
     helpURL: string;
+    _debouncedUpdateValidationErrorVisibility: Function;
 
     /**
      * Constructor for the component.
@@ -50,14 +64,45 @@ export default class AbstractStreamKeyForm extends Component<Props> {
     constructor(props: Props) {
         super(props);
 
+        this.state = {
+            showValidationError: Boolean(this.props.value)
+                && !this._validateStreamKey(this.props.value)
+        };
+
         this.helpURL = (typeof interfaceConfig !== 'undefined'
             && interfaceConfig.LIVE_STREAMING_HELP_LINK)
             || LIVE_STREAMING_HELP_LINK;
 
+        this._debouncedUpdateValidationErrorVisibility = debounce(
+            this._updateValidationErrorVisibility.bind(this),
+            800,
+            { leading: false }
+        );
+
         // Bind event handlers so they are only bound once per instance.
         this._onInputChange = this._onInputChange.bind(this);
     }
 
+    /**
+     * Implements React Component's componentDidUpdate.
+     *
+     * @inheritdoc
+     */
+    componentDidUpdate(prevProps: Props) {
+        if (this.props.value !== prevProps.value) {
+            this._debouncedUpdateValidationErrorVisibility();
+        }
+    }
+
+    /**
+     * Implements React Component's componentWillUnmount.
+     *
+     * @inheritdoc
+     */
+    componentWillUnmount() {
+        this._debouncedUpdateValidationErrorVisibility.cancel();
+    }
+
     _onInputChange: Object => void
 
     /**
@@ -75,4 +120,38 @@ export default class AbstractStreamKeyForm extends Component<Props> {
 
         this.props.onChange(value);
     }
+
+    /**
+     * Checks if the stream key value seems like a valid stream key and sets the
+     * state for showing or hiding the notification about the stream key seeming
+     * invalid.
+     *
+     * @private
+     * @returns {boolean}
+     */
+    _updateValidationErrorVisibility() {
+        const newShowValidationError = Boolean(this.props.value)
+            && !this._validateStreamKey(this.props.value);
+
+        if (newShowValidationError !== this.state.showValidationError) {
+            this.setState({
+                showValidationError: newShowValidationError
+            });
+        }
+    }
+
+    /**
+     * Checks if a passed in stream key appears to be in a valid format.
+     *
+     * @param {string} streamKey - The stream key to check for valid formatting.
+     * @returns {void}
+     * @returns {boolean}
+     */
+    _validateStreamKey(streamKey = '') {
+        const trimmedKey = streamKey.trim();
+        const fourGroupsDashSeparated = /^(?:[a-zA-Z0-9]{4}(?:-(?!$)|$)){4}/;
+        const match = fourGroupsDashSeparated.exec(trimmedKey);
+
+        return Boolean(match);
+    }
 }

react/features/recording/components/LiveStream/web/StreamKeyForm.js

@@ -36,7 +36,7 @@ class StreamKeyForm extends AbstractStreamKeyForm {
      * @returns {ReactElement}
      */
     render() {
-        const { value, t } = this.props;
+        const { t, value } = this.props;
 
         return (
             <div className = 'stream-key-form'>
@@ -52,16 +52,22 @@ class StreamKeyForm extends AbstractStreamKeyForm {
                     shouldFitContainer = { true }
                     type = 'text'
                     value = { this.props.value } />
-                { this.helpURL
+                <div className = 'form-footer'>
-                    ? <div className = 'form-footer'>
+                    { this.state.showValidationError
-                        <a
+                        ? <span className = 'validation-error'>
+                            { t('liveStreaming.invalidStreamKey') }
+                        </span>
+                        : null
+                    }
+                    { this.helpURL
+                        ? <a
                             className = 'helper-link'
                             onClick = { this._onOpenHelp }>
                             { t('liveStreaming.streamIdHelp') }
                         </a>
-                    </div>
+                        : null
-                    : null
+                    }
-                }
+                </div>
             </div>
         );
     }