How to use the openvidu-node-client.OpenViduRole.PUBLISHER function in openvidu-node-client

app.post('/api/get-token', function (req, res) {
    // The video-call to connect
    var sessionName = req.body.sessionName;

    // Role associated to this user
    var role = OpenViduRole.PUBLISHER;

    console.log("Getting a token | {sessionName}={" + sessionName + "}");

    // Build tokenOptions object with PUBLISHER role
    var tokenOptions = {
        role: role
    }

    if (mapSessions[sessionName]) {
        // Session already exists
        console.log('Existing session ' + sessionName);

        // Get the existing Session from the collection
        var mySession = mapSessions[sessionName];

        // Generate a new token asynchronously with the recently created tokenOptions

// Listen (start app with node server.js)
var options = {
    key: fs.readFileSync('openvidukey.pem'),
    cert: fs.readFileSync('openviducert.pem')
};
https.createServer(options, app).listen(5000);

// Mock database
var users = [{
    user: "publisher1",
    pass: "pass",
    role: OpenViduRole.PUBLISHER
}, {
    user: "publisher2",
    pass: "pass",
    role: OpenViduRole.PUBLISHER
}, {
    user: "subscriber",
    pass: "pass",
    role: OpenViduRole.SUBSCRIBER
}];

// Environment variable: URL where our OpenVidu server is listening
var OPENVIDU_URL = process.argv[2];
// Environment variable: secret shared with our OpenVidu server
var OPENVIDU_SECRET = process.argv[3];

// Entrypoint to OpenVidu Node Client SDK
var OV = new OpenVidu(OPENVIDU_URL, OPENVIDU_SECRET);

// Collection to pair session names with OpenVidu Session objects
var mapSessions = {};

type: 'application/vnd.api+json'
})); // Parse application/vnd.api+json as json
app.set('view engine', 'ejs'); // Embedded JavaScript as template engine

// Listen (start app with node server.js)
var options = {
    key: fs.readFileSync('openvidukey.pem'),
    cert: fs.readFileSync('openviducert.pem')
};
https.createServer(options, app).listen(5000);

// Mock database
var users = [{
    user: "publisher1",
    pass: "pass",
    role: OpenViduRole.PUBLISHER
}, {
    user: "publisher2",
    pass: "pass",
    role: OpenViduRole.PUBLISHER
}, {
    user: "subscriber",
    pass: "pass",
    role: OpenViduRole.SUBSCRIBER
}];

// Environment variable: URL where our OpenVidu server is listening
var OPENVIDU_URL = process.argv[2];
// Environment variable: secret shared with our OpenVidu server
var OPENVIDU_SECRET = process.argv[3];

// Entrypoint to OpenVidu Node Client SDK

// Listen (start app with node server.js)
var options = {
    key: fs.readFileSync('openvidukey.pem'),
    cert: fs.readFileSync('openviducert.pem')
};
https.createServer(options, app).listen(5000);

// Mock database
var users = [{
    user: "publisher1",
    pass: "pass",
    role: OpenViduRole.PUBLISHER
}, {
    user: "publisher2",
    pass: "pass",
    role: OpenViduRole.PUBLISHER
}, {
    user: "subscriber",
    pass: "pass",
    role: OpenViduRole.SUBSCRIBER
}];

// Environment variable: URL where our OpenVidu server is listening
var OPENVIDU_URL = process.argv[2];
// Environment variable: secret shared with our OpenVidu server
var OPENVIDU_SECRET = process.argv[3];

// Entrypoint to OpenVidu Node Client SDK
var OV = new OpenVidu(OPENVIDU_URL, OPENVIDU_SECRET);

// Collection to pair session names with OpenVidu Session objects
var mapSessions = {};

app.use(bodyParser.json({
    type: 'application/vnd.api+json'
})); // Parse application/vnd.api+json as json

// Listen (start app with node server.js)
var options = {
    key: fs.readFileSync('openvidukey.pem'),
    cert: fs.readFileSync('openviducert.pem')
};
https.createServer(options, app).listen(5000);

// Mock database
var users = [{
    user: "publisher1",
    pass: "pass",
    role: OpenViduRole.PUBLISHER
}, {
    user: "publisher2",
    pass: "pass",
    role: OpenViduRole.PUBLISHER
}, {
    user: "subscriber",
    pass: "pass",
    role: OpenViduRole.SUBSCRIBER
}];

// Environment variable: URL where our OpenVidu server is listening
var OPENVIDU_URL = process.argv[2];
// Environment variable: secret shared with our OpenVidu server
var OPENVIDU_SECRET = process.argv[3];

// Entrypoint to OpenVidu Node Client SDK