Firebase Storage generate Signed Url

firebase_storage_signed_url.js

var serviceAccount = require("./service/cred.json");

// admin.initializeApp(functions.config().firebase);
admin.initializeApp({
    credential: admin.credential.cert(serviceAccount),
});

const { Storage } = require('@google-cloud/storage');

const storage = new Storage();

const options = {
    action: 'read',
    expires: Date.now() + 1000 * 60 * 60, // one hour
};
// Get a signed URL for the file
storage
    .bucket(bucket_videos)
    .file('videos/' + videoId + '/' + videoId + "_360.mp4")
    .getSignedUrl(options)
    .then(singnedUrl => {
        console.log(singnedUrl[0])
        return null;
    })
    .catch(error => {
        console.log(error);
        console.log("Error");
    })