jiti-meet/react/features/subtitles/middleware.js

113 lines
4.1 KiB
JavaScript

import { MiddlewareRegistry } from '../base/redux';
import { ENDPOINT_MESSAGE_RECEIVED } from './actionTypes';
import {
addTranscriptMessage,
removeTranscriptMessage,
updateTranscriptMessage
} from './actions';
const logger = require('jitsi-meet-logger').getLogger(__filename);
/**
* Time after which the rendered subtitles will be removed.
*/
const REMOVE_AFTER_MS = 3000;
/**
* Middleware that catches actions related to transcript messages
* to be rendered in {@link TranscriptionSubtitles }
*
* @param {Store} store - Redux store.
* @returns {Function}
*/
MiddlewareRegistry.register(store => next => action => {
switch (action.type) {
case ENDPOINT_MESSAGE_RECEIVED:
return _endpointMessageReceived(store, next, action);
}
return next(action);
});
/**
* Notifies the feature transcription that the action
* {@code ENDPOINT_MESSAGE_RECEIVED} is being dispatched within a specific redux
* store.
*
* @param {Store} store - The redux store in which the specified {@code action}
* is being dispatched.
* @param {Dispatch} next - The redux {@code dispatch} function to
* dispatch the specified {@code action} to the specified {@code store}.
* @param {Action} action - The redux action {@code ENDPOINT_MESSAGE_RECEIVED}
* which is being dispatched in the specified {@code store}.
* @private
* @returns {Object} The value returned by {@code next(action)}.
*/
function _endpointMessageReceived({ dispatch, getState }, next, action) {
const json = action.json;
try {
// Let's first check if the given object has the correct
// type in the json, which identifies it as a json message sent
// from Jigasi with speech-to-to-text results
if (json.type === 'transcription-result') {
// Extract the useful data from the json.
const isInterim = json.is_interim;
const participantName = json.participant.name;
const stability = json.stability;
const text = json.transcript[0].text;
const transcriptMessageID = json.message_id;
// If this is the first result with the unique message ID,
// we add it to the state along with the name of the participant
// who said given text
if (!getState()['features/subtitles']
.transcriptMessages.has(transcriptMessageID)) {
dispatch(addTranscriptMessage(transcriptMessageID,
participantName));
}
const { transcriptMessages } = getState()['features/subtitles'];
const newTranscriptMessage
= { ...transcriptMessages.get(transcriptMessageID) };
// If this is final result, update the state as a final result
// and start a count down to remove the subtitle from the state
if (!isInterim) {
newTranscriptMessage.final = text;
dispatch(updateTranscriptMessage(transcriptMessageID,
newTranscriptMessage));
setTimeout(() => {
dispatch(removeTranscriptMessage(transcriptMessageID));
}, REMOVE_AFTER_MS);
} else if (stability > 0.85) {
// If the message has a high stability, we can update the
// stable field of the state and remove the previously
// unstable results
newTranscriptMessage.stable = text;
newTranscriptMessage.unstable = undefined;
dispatch(updateTranscriptMessage(transcriptMessageID,
newTranscriptMessage));
} else {
// Otherwise, this result has an unstable result, which we
// add to the state. The unstable result will be appended
// after the stable part.
newTranscriptMessage.unstable = text;
dispatch(updateTranscriptMessage(transcriptMessageID,
newTranscriptMessage));
}
}
} catch (error) {
logger.error('Error occurred while updating transcriptions\n', error);
}
return next(action);
}