javascript - 范围问题 : storing account credentials in a new class object within a promise, 但现在需要在类的其余部分使用此对象

Question

我已成功从 Firebase 检索数据以设置为客户端 ID 和客户端密码。为此，我必须使用 promise.then 以确保设置的凭据在检索数据后发生。

const SpotifyWebApi = require('spotify-web-api-node');
admin.firestore().collection('credentials').get().then((snapshot) => {
    snapshot.docs.forEach(doc => {
        console.log(JSON.stringify(doc.data().client_id));
        // Credentials.client_id = JSON.stringify(doc.data().client_id);
        console.log(JSON.stringify(doc.data().client_secret));
        // Credentials.client_secret = JSON.stringify(doc.data().client_secret);
        let client_id = JSON.stringify(doc.data().client_id);
        let client_secret = JSON.stringify(doc.data().client_secret);
        const credentials = new Credentials(regexIdAndSecret(client_id), regexIdAndSecret(client_secret));




        const Spotify = new SpotifyWebApi({
            client_id: credentials.client_id,
            client_secret: credentials.client_secret,
            redirectUri: `https://${process.env.GCLOUD_PROJECT}.firebaseapp.com/popup.html`
        });
        console.log('This is the client id after it has been set ' + credentials.client_id);
        console.log('This is the client secret after it has been set ' + credentials.client_secret);

    });


});

但是，我现在遇到了需要在其余代码中使用“Spotify”的困境。因为它在这个 promise 中，所以它的范围仅限于 promise 内部。如何使用正确检索的 Firebase 数据设置凭据，以便“Spotify”对象适用于整个类(class)？

我在下面使用 Spotify 对象的另一个地方的示例(但现在不工作，因为 Spotify 不再是类对象:

/**
 * Redirects the User to the Spotify authentication consent screen. Also the 'state' cookie is set for later state
 * verification.
 */
exports.redirect = functions.https.onRequest((req, res) => {

    cookieParser()(req, res, () => {

        const state = req.cookies.state || crypto.randomBytes(20).toString('hex');
        console.log('Setting verification state:', state);
        res.cookie('state', state.toString(), {maxAge: 3600000, secure: true, httpOnly: true});
        const authorizeURL = Spotify.createAuthorizeURL(OAUTH_SCOPES, state.toString());
        res.redirect(authorizeURL);
    });
});

整个文件:

/**
 * Main class holding all the logic which matches the Google assistant application to the Firebase database
 * and the Spotify dashboard application. The application is formatted to reflect these three main parts with
 * response-requests to Spotify for authorisation and to make api function calls (within the dialogflow fulfillment
 * code towards the bottom of the class).
 * Author: Marcus Watts
 * Date Created: 01 July 2019
 */
'use strict';


/**
 * --------------------------- Google/Dialogflow/Firebase Setup ---------------------------
 * @type {{analytics; auth; crashlytics; database; firestore; https; pubsub; remoteConfig; storage; testLab; app: apps.Apps; Event: Event; EventContext: EventContext; Change: Change; ChangeJson: ChangeJson; Resource: Resource; TriggerAnnotated: TriggerAnnotated; Runnable: Runnable; HttpsFunction: HttpsFunction; CloudFunction: CloudFunction; MakeCloudFunctionArgs: MakeCloudFunctionArgs; makeCloudFunction; optionsToTrigger; config; firebaseConfig; region; runWith; FunctionBuilder: FunctionBuilder; SUPPORTED_REGIONS: readonly; MIN_TIMEOUT_SECONDS: number; MAX_TIMEOUT_SECONDS: number; VALID_MEMORY_OPTIONS: readonly; ScheduleRetryConfig: ScheduleRetryConfig; Schedule: Schedule; RuntimeOptions: RuntimeOptions; DeploymentOptions: DeploymentOptions}}
 */

//  Modules being used
const functions = require('firebase-functions');
// Sets this file as the webhook for dialogflow filfillment
const {WebhookClient} = require('dialogflow-fulfillment');
// Used for storing the sign in data of the Spotify user
const cookieParser = require('cookie-parser');
const crypto = require('crypto');

// Firebase Setup
const admin = require('firebase-admin');
const serviceAccount = require('./service-account.json');
admin.initializeApp({
    credential: admin.credential.cert(serviceAccount),
    databaseURL: `https://${process.env.GCLOUD_PROJECT}.firebaseio.com`
});

// async function getCredentials() {
//     const snapshot = await admin.firestore().collection('credentials').get();
//     return snapshot;
// }
//


class Credentials {

    constructor(client_id, client_secret) {
        this.client_id = client_id;
        console.log('Id in class ' + this.client_id);
        this.client_secret = client_secret;
        console.log('Secret in class ' + this.client_secret);

    }


}

/**
 * ----------------------Below section of code found at: LINK TO GIT REPOSTITORY---------------------------------
 */

function regexIdAndSecret(clientIdOrSecret){
    const regex = /[(\w)]+/g;
    let n;
    let match;
    while ((n = regex.exec(clientIdOrSecret)) !== null) {
        // This is necessary to avoid infinite loops with zero-width matches
        if (n.index === regex.lastIndex) {
            regex.lastIndex++;
        }

        // The result can be accessed through the `n`-variable.
        n.forEach((match, groupIndex) => {
            return match;
            console.log(`Found match, group ${groupIndex}: ${match}`);

        });
        console.log(`Found n,  ${n}`);
        return n;
    }

}


// Spotify OAuth 2 setup
const SpotifyWebApi = require('spotify-web-api-node');
admin.firestore().collection('credentials').get().then((snapshot) => {
    snapshot.docs.forEach(doc => {
        console.log(JSON.stringify(doc.data().client_id));
        // Credentials.client_id = JSON.stringify(doc.data().client_id);
        console.log(JSON.stringify(doc.data().client_secret));
        // Credentials.client_secret = JSON.stringify(doc.data().client_secret);
        let client_id = JSON.stringify(doc.data().client_id);
        let client_secret = JSON.stringify(doc.data().client_secret);
        const credentials = new Credentials(regexIdAndSecret(client_id), regexIdAndSecret(client_secret));




        const Spotify = new SpotifyWebApi({
            client_id: credentials.client_id,
            client_secret: credentials.client_secret,
            redirectUri: `https://${process.env.GCLOUD_PROJECT}.firebaseapp.com/popup.html`
        });
        console.log('This is the client id after it has been set ' + credentials.client_id);
        console.log('This is the client secret after it has been set ' + credentials.client_secret);

    });

// Scopes to request. (Added in all the possible scopes for the auth so that it is possible to do any action that the
// Spotify api will allow i.e maximum permissions granted)
const OAUTH_SCOPES = [
    'user-read-email',
    'app-remote-control',
    'streaming',
    'user-modify-playback-state',
    'playlist-read-private',
    'user-library-modify',
    'playlist-read-collaborative',
    'playlist-modify-private',
    'user-follow-modify',
    'user-read-currently-playing',
    'user-read-email',
    'user-library-read',
    'user-top-read',
    'playlist-modify-public',
    'user-follow-read',
    'user-read-playback-state',
    'user-read-recently-played'
];

/**
 * Redirects the User to the Spotify authentication consent screen. Also the 'state' cookie is set for later state
 * verification.
 */
exports.redirect = functions.https.onRequest((req, res) => {

    cookieParser()(req, res, () => {

        const state = req.cookies.state || crypto.randomBytes(20).toString('hex');
        console.log('Setting verification state:', state);
        res.cookie('state', state.toString(), {maxAge: 3600000, secure: true, httpOnly: true});
        const authorizeURL = Spotify.createAuthorizeURL(OAUTH_SCOPES, state.toString());
        res.redirect(authorizeURL);
    });
});


/**
 * Exchanges a given Spotify auth code passed in the 'code' URL query parameter for a Firebase auth token.
 * The request also needs to specify a 'state' query parameter which will be checked against the 'state' cookie.
 * The Firebase custom auth token is sent back in a JSONP callback function with function name defined by the
 * 'callback' query parameter.
 */
exports.token = functions.https.onRequest((req, res) => {
    try {
        cookieParser()(req, res, () => {
            console.log('Received verification state:', req.cookies.state);
            console.log('Received state:', req.query.state);
            if (!req.cookies.state) {
                throw new Error(
                    'State cookie not set or expired. Maybe you took too long to authorize. Please try again.'
                );
            } else if (req.cookies.state !== req.query.state) {
                throw new Error('State validation failed');
            }
            console.log('Received auth code:', req.query.code);
            Spotify.authorizationCodeGrant(req.query.code, (error, data) => {
                if (error) {
                    throw error;
                }
                /**
                 * Store the codes retained from the Authorization. (Added in the refresh token so that it can be used and set as appropriate to ensure
                 * the user is constantly connected to the Spotify api)
                 */
                console.log('Received Access Token:', data.body['access_token']);
                console.log('Received Refresh Token:', data.body['refresh_token']);
                Spotify.setAccessToken(data.body['access_token']);
                Spotify.setRefreshToken(data.body['refresh_token']);
                // setterForRefreshToken(data.body['refresh_token']);
                Spotify.getMe(async (error, userResults) => {
                    if (error) {
                        throw error;
                    }
                    console.log('Auth code exchange result received:', userResults);
                    // We have a Spotify access token and the user identity now.
                    const accessToken = data.body['access_token'];
                    const spotifyUserID = userResults.body['id'];
                    const profilePic = userResults.body['images'][0]['url'];
                    const userName = userResults.body['display_name'];
                    const email = userResults.body['email'];

                    // Create a Firebase account and get the Custom Auth Token.
                    const firebaseToken = await createFirebaseAccount(
                        spotifyUserID,
                        userName,
                        profilePic,
                        email,
                        accessToken
                    );
                    // Serve an HTML page that signs the user in and updates the user profile.
                    res.jsonp({token: firebaseToken});
                });
            });
        });
    } catch (error) {
        return res.jsonp({error: error.toString});
    }
    return null;
});

/**
 * Creates a Firebase account with the given user profile and returns a custom auth token allowing
 * signing-in this account.
 * Also saves the accessToken to the datastore at /spotifyAccessToken/$uid
 *
 * @returns {Promise<string>} The Firebase custom auth token in a promise.
 */
async function createFirebaseAccount(spotifyID, displayName, photoURL, email, accessToken) {
    // The UID we'll assign to the user.
    const uid = `spotify:${spotifyID}`;

    // Save the access token to the Firebase Realtime Database.
    const databaseTask = admin.database().ref(`/spotifyAccessToken/${uid}`).set(accessToken);

    // Create or update the user account.
    const userCreationTask = admin
        .auth()
        .updateUser(uid, {
            displayName: displayName,
            photoURL: photoURL,
            email: email,
            emailVerified: true
        })
        .catch((error) => {
            // If user does not exists we create it.
            if (error.code === 'auth/user-not-found') {
                return admin.auth().createUser({
                    uid: uid,
                    displayName: displayName,
                    photoURL: photoURL,
                    email: email,
                    emailVerified: true
                });
            }
            throw error;
        });

    // Wait for all async tasks to complete, then generate and return a custom auth token.
    await Promise.all([userCreationTask, databaseTask]);
    // Create a Firebase custom auth token.
    const token = await admin.auth().createCustomToken(uid);
    console.log('Created Custom token for UID "', uid, '" Token:', token);
    return token;
}

/**
 * ----------------- Classes for storing the refresh and access tokens which are attained at sign in:-----------------
 * used to create instance variables which can be accessible anywhere within the class
 */

class Refresh {
    // Instance variables store the refresh token
    constructor(refresh_token) {
        this.refresh_token = refresh_token;
    }
}

// Instance variables store the refresh token
class Access {
    constructor(accessToken) {
        this.accessToken = accessToken;
    }
}


/**
 * ---------------------------Setter and Getter Functions for Spotify Auth URL--------------------------------
 */

function setterForUpdatedAccessToken(splitString) {
    Access.accessToken = splitString;
    console.log('This is the access token being set in setterForUpdatedAccessToken', Access.accessToken);
}

function getterForUpdatedAccessToken() {
    console.log('This is the access token being get in getterForUpdatedAccessToken', Access.accessToken);
    return JSON.stringify(Access.accessToken);
}

更新:获取错误 Cannopt read property 'createAuthorizeURL' of undefined at spotify.then.Spotify

const spotify = admin.firestore().collection('credentials').get().then((snapshot) => {
    snapshot.docs.forEach(doc => {
        console.log(JSON.stringify(doc.data().client_id));
        // Credentials.client_id = JSON.stringify(doc.data().client_id);
        console.log(JSON.stringify(doc.data().client_secret));
        // Credentials.client_secret = JSON.stringify(doc.data().client_secret);
        let client_id = JSON.stringify(doc.data().client_id);
        let client_secret = JSON.stringify(doc.data().client_secret);
        const credentials = new Credentials(regexIdAndSecret(client_id), regexIdAndSecret(client_secret));


        const Spotify = new SpotifyWebApi({
            client_id: credentials.client_id,
            client_secret: credentials.client_secret,
            redirectUri: `https://${process.env.GCLOUD_PROJECT}.firebaseapp.com/popup.html`
        });
        console.log('This is the client id after it has been set ' + credentials.client_id);
        console.log('This is the client secret after it has been set ' + credentials.client_secret);
        return Spotify;
    });



});

exports.redirect = functions.https.onRequest((req, res) => {

    cookieParser()(req, res, () => {

        const state = req.cookies.state || crypto.randomBytes(20).toString('hex');
        console.log('Setting verification state:', state);
        res.cookie('state', state.toString(), {maxAge: 3600000, secure: true, httpOnly: true});
        spotify.then(Spotify => {
            const authorizeURL = Spotify.createAuthorizeURL(OAUTH_SCOPES, state.toString());
            res.redirect(authorizeURL);
        });
    });
});

Answer 1

从您的 .then 回调返回 spotify 类实例，并将 promise 存储在您所有其他代码可访问的某个地方。例如。在文件顶部或在单独的模块中:

// spotify.js
module.exports = admin.firestore().collection('credentials').get().then((snapshot) => {
  /*...*/
  return Spotify;
});

您可以在代码中的任何其他地方

const spotify = require('./spotify');
// ...
spotify.then(Spotify => {
  // do stuff with Spotify
});

当然，如果您在异步函数中，您可以只使用 await(但我会选择不同的变量名称):

const Spotify = await spotify;
// do stuff with Spotify

例如:

const spotify = require('./spotify');
// ...
exports.redirect = functions.https.onRequest((req, res) => {

    cookieParser()(req, res, () => {

        const state = req.cookies.state || crypto.randomBytes(20).toString('hex');
        console.log('Setting verification state:', state);
        res.cookie('state', state.toString(), {maxAge: 3600000, secure: true, httpOnly: true});
        spotify.then(Spotify => {
            const authorizeURL = Spotify.createAuthorizeURL(OAUTH_SCOPES, state.toString());
            res.redirect(authorizeURL);
        });
    });
});