room-lock: adds ability to allow only digits for room locking

config.js

     // Enable lock room for all moderators, even when userRolesBasedOnToken is enabled and participants are guests.
     // lockRoomGuestEnabled: false,
 
+    // When enabled the password used for locking a room is restricted to up to the number of digits specified
+    // roomPasswordNumberOfDigits: 10,
+    // default: roomPasswordNumberOfDigits: false,
+
     // Message to show the users. Example: 'The service will be down for
     // maintenance at 01:00 AM GMT,
     // noticeMessage: '',

lang/main.json

         "newDeviceAction": "Use"
     },
     "passwordSetRemotely": "set by another member",
+    "passwordDigitsOnly": "Up to __number__ digits",
     "poweredby": "powered by",
     "presenceStatus": {
         "busy": "Busy",

react/features/base/dialog/components/native/InputDialog.js

 
     t: Function,
 
-    textInputProps: ?Object
+    textInputProps: ?Object,
+
+    /**
+     * Validating of the input.
+     */
+    validateInput: ?Function
 }
 
 type State = {
      * @returns {void}
      */
     _onChangeText(fieldValue) {
+
+        if (this.props.validateInput
+                && !this.props.validateInput(fieldValue)) {
+            return;
+        }
+
         this.setState({
             fieldValue
         });

react/features/invite/components/info-dialog/web/InfoDialog.js

      */
     _conferenceName: string,
 
+    /**
+     * The number of digits to be used in the password.
+     */
+    _passwordNumberOfDigits: ?number,
+
     /**
      * The current url of the conference to be copied onto the clipboard.
      */
                             editEnabled = { this.state.passwordEditEnabled }
                             locked = { this.props._locked }
                             onSubmit = { this._onPasswordSubmit }
-                            password = { this.props._password } />
+                            password = { this.props._password }
+                            passwordNumberOfDigits = { this.props._passwordNumberOfDigits } />
                     </div>
                     <div className = 'info-dialog-action-links'>
                         <div className = 'info-dialog-action-link'>
         _canEditPassword: isLocalParticipantModerator(state, state['features/base/config'].lockRoomGuestEnabled),
         _conference: conference,
         _conferenceName: room,
+        _passwordNumberOfDigits: state['features/base/config'].roomPasswordNumberOfDigits,
         _inviteURL: getInviteURL(state),
         _localParticipant: getLocalParticipant(state),
         _locationURL: state['features/base/connection'].locationURL,

react/features/invite/components/info-dialog/web/PasswordForm.js

      */
     password: string,
 
+    /**
+     * The number of digits to be used in the password.
+     */
+    passwordNumberOfDigits: boolean,
+
     /**
      * Invoked to obtain translated strings.
      */
      */
     _renderPasswordField() {
         if (this.props.editEnabled) {
+            let digitPattern, placeHolderText;
+
+            if (this.props.passwordNumberOfDigits) {
+                placeHolderText = this.props.t('passwordDigitsOnly', {
+                    number: this.props.passwordNumberOfDigits });
+                digitPattern = '\\d*';
+            }
+
             return (
                 <form
                     className = 'info-password-form'
                     <input
                         autoFocus = { true }
                         className = 'info-password-input'
+                        maxLength = { this.props.passwordNumberOfDigits }
                         onChange = { this._onEnteredPasswordChange }
+                        pattern = { digitPattern }
+                        placeholder = { placeHolderText }
                         spellCheck = { 'false' }
                         type = 'text'
                         value = { this.state.enteredPassword } />

react/features/room-lock/actions.js

             conference = getState()['features/base/conference'].conference;
         }
         if (conference) {
-            dispatch(openDialog(RoomLockPrompt, { conference }));
+            const passwordNumberOfDigits = getState()['features/base/config'].roomPasswordNumberOfDigits;
+
+            dispatch(openDialog(RoomLockPrompt, {
+                conference,
+                passwordNumberOfDigits }));
         }
     };
 }

react/features/room-lock/components/RoomLockPrompt.native.js

      */
     conference: Object,
 
+    /**
+     * The number of digits to be used in the password.
+     */
+    passwordNumberOfDigits: ?number,
+
     /**
      * Redux store dispatch function.
      */
-    dispatch: Dispatch<any>,
+    dispatch: Dispatch<any>
 };
 
 /**
         // Bind event handlers so they are only bound once per instance.
         this._onCancel = this._onCancel.bind(this);
         this._onSubmit = this._onSubmit.bind(this);
+        this._validateInput = this._validateInput.bind(this);
     }
 
     /**
      * @returns {ReactElement}
      */
     render() {
+        let textInputProps = _TEXT_INPUT_PROPS;
+
+        if (this.props.passwordNumberOfDigits) {
+            textInputProps = {
+                ...textInputProps,
+                keyboardType: 'number-pad',
+                maxLength: this.props.passwordNumberOfDigits
+            };
+        }
+
         return (
             <InputDialog
                 contentKey = 'dialog.passwordLabel'
                 onCancel = { this._onCancel }
                 onSubmit = { this._onSubmit }
-                textInputProps = { _TEXT_INPUT_PROPS } />
+                textInputProps = { textInputProps }
+                validateInput = { this._validateInput } />
         );
     }
 
 
         return false; // Do not hide.
     }
+
+    _validateInput: (string) => boolean;
+
+    /**
+     * Verifies input in case only digits are required.
+     *
+     * @param {string|undefined} value - The submitted value.
+     * @private
+     * @returns {boolean} False when the value is not valid and True otherwise.
+     */
+    _validateInput(value: string) {
+
+        // we want only digits, but both number-pad and numeric add ',' and '.' as symbols
+        if (this.props.passwordNumberOfDigits
+            && value.length > 0
+            && !/^\d+$/.test(value)) {
+
+            return false;
+        }
+
+        return true;
+    }
 }
 
 export default connect()(RoomLockPrompt);