google-api-nodejs-client / How to decode the id_token received from oauth2Client.getToken - node.js

How to decode the id_token received from oauth2Client.getToken to get access to the JWT JSON fields email, sub, ..? Is there a function included in the google-api-nodejs-client lib?
In https://developers.google.com/accounts/docs/OpenIDConnect in says:
Since most API libraries combine the validation with the work of decoding the base64 and parsing the JSON, you will probably end up validating the token anyway as you access the fields in the ID token.
oauth2Client.getToken(req.query.code, function(err, tokens) {
// how to decode tokens.id_token to get
});

According to RFC, the JSON Web Token, when encoded, is composed of three parts (each part being a base64-encoded JSON object), separated by dots:
Header
Actual data
Signature
The header is pretty much a constant when used with Google APIs. You are going to need the second part.
To visualise this even better, take a look at jwt.io - it will show you the exact structure of the encoded token, in colours!:)
I recommend that you study carefully how it works, then install an npm module (there's aplenty around, search for jwt) to do the actual decoding for you.

here is the documentation
Just in case the Google documentation would be refactored in the future:
const {OAuth2Client} = require('google-auth-library');
const client = new OAuth2Client(CLIENT_ID);
async function verify() {
const ticket = await client.verifyIdToken({
idToken: token,
audience: CLIENT_ID, // Specify the CLIENT_ID of the app that accesses the backend
// Or, if multiple clients access the backend:
//[CLIENT_ID_1, CLIENT_ID_2, CLIENT_ID_3]
});
const payload = ticket.getPayload();
const userid = payload['sub'];
// If request specified a G Suite domain:
// const domain = payload['hd'];
}
verify().catch(console.error);
Also available here
Note that I was using #googleapis/oauth2 instead of google-auth-library but I noticed #googleapis/oauth2:
[Deprecated] Obtains end-user authorization grants for use with other Google APIs.
So I guess google-auth-library is the right choice.

Related

Docusign run code grant steps programmatically in node?

New to docusign and have been reading the docs, and I can't seem to get around these problems.
Per the docs it says that gets a code getAuthorizationUri() which can then be used by generateAccessToken() to get a token. After that, the token can be used to explore the API with other methods.
I'm stuck in two places: First I configured my get Authorization like this (typescript)
import { ApiClient } from 'docusign-esign'
const apiClient = new ApiClient()
const url: string = apiClient.getAuthorizationUri(
config.docusign.INTERGRATION_KEY,
['signature'],
'http://localhost/',
'code',
'ready'
)
console.log(url)
I get the url fine, but it is always starts with acccounts.docusign as opposed to the required account-d.docusign that's required because my app is in dev.
Secondly, I can't figure out how to transition that URL into a code programtically. Yes, I can copy and paste it from the browser URL (as in the instruction videos), but obviously my next step is to run something like:
async getToken(authCode){
const token = await apiClient.generateAccessToken(
INTERGRATION_KEY,
SECRET_KEY,
authCode
)
console.log(token)
return token
}
To change authentication from prod to demo, you need to make this call:
apiClient.setOAuthBasePath("account-d.docusign.com");
You may also want to change the URL for API calls if you use this later like this:
apiClient.setBasePath("https://demo.docusign.net/restapi");
I suggest using an OAuth npm package and not doing this yourself.
See how it's done in the quickstart (Pick Node.js and Auth Code Grant)

How do I get the access token without using the browser

When I go to the following URL in the browser with my own client_id:
https://account-d.docusign.com/oauth/auth?response_type=token&scope=signature&client_id=6d1a8594-xxxx-xxxx-xxxx-878e593de049&state=a39fh23hnf23&redirect_uri=http://localhost:8888/auth
I need to login and afterwards I get redirected to:
http://localhost:8888/auth#access_token=myAccessToken&expires_in=28800&token_type=bearer&state=a39fh23hnf23
Now I have a node.js application where I want to make API calls using my access token, until now I did the above manually every time to get my access token, of course, this isn't optimal. My question, therefore, is: how do I get my access token without using the browser?
Right now I have the following
sendRequestAccessToken(): Promise<any> {
const scope = 'signature';
const clientId = '*my client id*';
const state = 'a39fh23hnf23';
const url = `https://account-d.docusign.com/oauth/auth?
response_type=token
&scope=${scope}
&client_id=${clientId}
&state=${state}
&redirect_uri=http://localhost:8888/auth
`;
return this.httpService.get(url).toPromise(); }
The response from this function contains a lot of data, but no access token.
Please review the SDK examples we have here: https://github.com/docusign/code-examples-node
In those samples, we have examples on how to use the tokens using the apis.

How to implement authentication in Next.js

I am new to Next.js and I am struggling with the authentication system using jwt token. I want to know what is the best / standard way to store the jwt token and routing with the authentication system. I have been trying different approaches, from different tutorials/articles, but do not quite understand it. Here are what I have tried.
When the user login, it sends username/password to a separated API server (ex. new project that handles backend stuff), the server will respond with the access-token, then in Next.js project, I set the cookie with that received token. In Next.js project, protected routes will be wrapped with a withAuth hoc, which will check for the token in a cookie. The problem with this approach is that it is vulnerable to XSS because the cookie has no httpOnly flag.
This is similar to 1.) but using localStorage, the problem is access-token could not be sent to the server on the first request. (This one I'm not sure, but in my understanding, in every HTTP request, I must stick my access-token manually, so what about requests that I have no control over? ex. first request or using <a> tag).
I wrote authentication backend inside Next.js server (custom express server). When the user login, the server will validate it and then set an httpOnly cookie. Then the problem is, with client-side routing (go to URL using Next.js Router), it could not check for token. For example, if a page is wrapped with withAuth hoc, but it cannot access the token inside cookies with javascript.
And I've seen a lot of people, in getInitialProps of the protected route, they only check for existence token in cookie / localStorage, then what if the token is being revoked or blacklisted, how do they handle it because they did not send the token to the server? Or do I have to send the token to the server in every client-side page change?
Since we are on quarantine I have enough time to answer this question. It will be a long answer.
Next.js uses the App component to initialize the pages. _app page is responsible for rendering our pages. We authenticate users on _app.js because anything that we return from getInitialProps can be accessed by all of the other pages. We authenticate user here, authentication decision will be passed to pages, from pages to header, so each page can decide if the user is authenticated or not. (Note that it could be done with redux without prop drilling but it would make the answer more complex)
static async getInitialProps({ Component, router, ctx }) {
let pageProps = {};
const user = process.browser
? await auth0.clientAuth()
: await auth0.serverAuth(ctx.req); // I explain down below
//this will be sent to all the components
const auth = { user, isAuthenticated: !!user };
if (Component.getInitialProps) {
pageProps = await Component.getInitialProps(ctx);
}
return { pageProps, auth };
}
render() {
const { Component, pageProps, auth } = this.props;
return <Component {...pageProps} auth={auth} />;
}
}
If we are on the browser and need to check if a user is authenticated, we just retrieve the cookie from the browser, which is easy. But we always have to verify the token. It is the same process used by browser and server. I will explain down below. But if we are on the server. we have no access to the cookies in the browser. But we can read from the "req" object because cookies are attached to the req.header.cookie. this is how we access to cookies on the server.
async serverAuth(req) {
// console.log(req.headers.cookie) to check
if (req.headers.cookie) {
const token = getCookieFromReq(req, "jwt");
const verifiedToken = await this.verifyToken(token);
return verifiedToken;
}
return undefined;
}
here is getCookieFromReq(). remember we have to think functional.
const getCookieFromReq = (req, cookieKey) => {
const cookie = req.headers.cookie
.split(";")
.find((c) => c.trim().startsWith(`${cookieKey}=`));
if (!cookie) return undefined;
return cookie.split("=")[1];
};
Once we get the cookie, we have to decode it, extract the expiration time to see if it is valid or not. this part is easy. Another thing we have to check is if the signature of the jwt is valid. Symmetric or asymmetric algorithms are used to sign the jwt. You have to use private keys to validate the signature of symmetric algorithms. RS256 is the default asymmetric algorithms for APIs. Servers that use RS256, provide you with a link to get jwt to use the keys to validate the signature. You can either use [jwks-rsa][1] or you can do on your own. You have to create a certificate and then verify if the token is valid.
Assume that our user authenticated now. You said, "And I've seen a lot of people, in getInitialProps of the protected route, they only check for existence token in cookie / localStorage,". We use protected routes to give access only to the authorized users. In order to access those routes, users have to show their jwt tokens and express.js uses middlewares to check if the user's token is valid. Since you have seen a lot of examples, I will skip this part.
"then what if the token is being revoked or blacklisted, how do they handle it because they did not send the token to the server? Or do I have to send the token to a server in every client-side page changing?"
with verifying token process we are 100% sure if the token is valid or not. When a client asks the server to access some secret data, the client has to send the token to the server. Imagine when you mount the component, component asks the server to get some data from the protected routes. The server will extract the req object, take the jwt and use it to fetch data from the protected routes. Implementation of the fetching data for browser and server are different. And if the browser makes a request, it just needs the relative path but the server needs an absolute path. As you should know fetching data is done getInitialProps() of the component and this function executed on both client and server. here is how you should implement it. I just attached the getInitialProps() part.
MyComponent.getInitialProps = async (ctx) => {
const another = await getSecretData(ctx.req);
//reuslt of fetching data is passed to component as props
return { superValue: another };
};
const getCookieFromReq = (req, cookieKey) => {
const cookie = req.headers.cookie
.split(";")
.find((c) => c.trim().startsWith(`${cookieKey}=`));
if (!cookie) return undefined;
return cookie.split("=")[1];
};
const setAuthHeader = (req) => {
const token = req ? getCookieFromReq(req, "jwt") : Cookies.getJSON("jwt");
if (token) {
return {
headers: { authorization: `Bearer ${token}` },
};
}
return undefined;
};
export const getSecretData = async (req) => {
const url = req ? "http://localhost:3000/api/v1/secret" : "/api/v1/secret";
return await axios.get(url, setAuthHeader(req)).then((res) => res.data);
};
[1]: https://www.npmjs.com/package/jwks-rsa
With the introduction of Next.JS v8, there are examples placed in the NextJS example page. The basic idea to follow is:
JWT
Using cookies to store the token (you may choose to further encrypt it or not)
Sending the cookies as authorization headers
OAuth
Using a third-party authentication service such as OAuth2.0
Using Passport
This question might need an updated answer, now middlewares are there in Next.js 12 (october 2021): https://nextjs.org/docs/middleware
I am drafting a comprehensive answer to explain auth in Next.js more deeply, you can follow the progress there on GitHub
Here I'll try to propose a summary for Next.js, using middlewares.
Verifying the token after auth and redirecting accordingly
Most of the answer from #Yilmaz from april 2020 is still relevant. However, previously, we had to use getInitialProps in _app to process the request OR a custom server.
This is no longer the case.. Using a middleware let's you achieve a similar purpose, with cleaner code. Because middleware are specifically designed for such use cases.
Here, I suppose you get a JWT access token using an asymetrical algorithm like RS256, exactly like in this previous answer.
Here is a possible implementation:
import { NextFetchEvent, NextRequest, NextResponse } from "next/server";
const removeCookie = (res: NextResponse, cookieName: string) => {
res.headers.append("Set-Cookie", `${cookieName}=; Max-Age=-1; Path=/`);
return res;
};
export default async function middleware(
req: NextRequest,
ev: NextFetchEvent
) {
const { pathname } = req.nextUrl;
const isPublic = isPublicRoute(pathname);
if (isPublic) {
return NextResponse.next();
}
const accessToken = req.cookies[TOKEN_PATH];
if (!accessToken) {
return NextResponse.redirect(LOGIN_HREF);
}
const isValidToken = await checkAccessToken(accessToken);
if (!isValidToken) {
let res = NextResponse.redirect(LOGIN_HREF);
res = removeCookie(res, TOKEN_PATH);
return res;
}
return NextResponse.next();
}
How to verify the token
In my example, the checkAccessToken should verify the token (not decode, verify the signature).
This is where things are the most complicated imo.
When using the RSA256 algorithm
You also get a PUBLIC certificate (in addition to the SECRET key that must be... kept secret). Eventhough you do the check in the middleware, which is private and server-only code, that's good news because it means you could even use it in the browser, in theory.
So, you can either fetch the token validation endpoint provided by your auth server, or verify the token yourself.
Fetching is not the recommended option because it might break Vercel/Next edge capabilities and add latency, according to the documentation.
I must admit that I did not succeed to verify the token yet using Next.js :) I'll update this answer if I manage to have a code sample that works.
When using a symmetrical encryption
You have only a PRIVATE secret passphrase. It means that the decoding have to happen server-side (good news, you are writing a middleware).
Login/logout
This doesn't change with middlewares. You store your access token as an httpOnly cookie. When logging out, you unset this cookie.
Managing those Set-Cookies headers are the responsibility of your auth server.
This is a basic workflow but it should work. You can then add a refresh token in the mix with a similar approach.
About token revokation
If you verify the token in your middleware, there is no immediate revokation mechanism for the access token. Because there is no call to a database.
Therefore, in this scenario, you'd want to opt-in for short lived access token (eg 5 minutes) coupled with a refresh token. You can revoke the refresh token, so basically revoking works but takes a few minutes.
If a 3rd party server verifies the token: then it could check for blacklisted tokens.
Caveats
Also, some piece of advice: most articles, tutorials etc. online are focused on server-to-server communication. Or client-to-API. They completely suck when it comes to check authentication before accessing web pages.
For instance, setting the Authorization header is not possible in the browser. It works only when communicating with an API. Cookies are mandatory for web pages.
Even then, if this API is meant to be called from a browser, it should preferably accept a cookie.
When discussing with experts on the field, you need to always clarify the Next.js use case.
Open questions: about session-based authentication
Some frameworks seem to prefer relying on the database. They store a hashed token in the db, which acts as a session. If you want to check auth, you need a server that will check the user's token against the stored token (= checking that there is an active session with this token).
I am thinking of Meteor for instance.
I couldn't find the name of this mechanism and its actual relation to JWT however. Are they simply variations of the JWT approach?
Next.js official authentication doc is not showing middlewares at the time of writing, but instead use getServerSideProps. I really don't like this pattern.
It uses a kind of session system but I am not clear about the internals of it, I am not even sure of the name (is that session-based auth?).
Vercel edge handles examples shows how to secure an API route, but not a page (at the time of writing)

Which data put in jwt-tokens (node.js + mongoose)?

Sorry for bad English.
To generate JWT-token i'm using
jwt = require('jsonwebtoken');
/* some code */
//function to create jwt-token
function createToken(user) {
return jwt.sign(user, config.secret, { expiresIn: 60*60*5 });
}
/* some code */
//after registration/authorization (if success) createToken token function is calling
createToken(user);
I would like to learn the best practices, what data must be passed to a function to create the token.
For example, can this be as:
login (John) and id( ObjectId("5821d94dbb021a1360582da3") when using MongoDb)?
And here, I think, will be relevant question:
If I store in token some information that allows initialize user, I can pull its data from the database. Is this correct, initialize the user from authorization header from JWT? For initialization I'm using express-jwt, which, if successful, sets req.user?
Thanks.
you can put the generated token in browser local storage, if you are using browser. You can also store session values in the token itself, those values will be decoded on the server side by nodejs.

Sync contacts using Google Contacts API version 3.0 and NodeJS' Passport

I am using passport, and would like to use the Google Contacts API version 3.0 to sync Google contacts with my application (which would suddenly become 10 times more useful).
Has anybody done this? If so, do you have some example code? Is it even possible to use passport authentication to get it all working?
This comes in two parts, authorization, and then the actual request.
It is basically using OAuth2 protocol, where you redirect the client to google url with scopes(You must at least have https://www.google.com/m8/feeds in your scopes to be able to read and write contacts) and your client id/secret(get them by registering your app. Then google will redirect the user back with the access token on the URL.
You don't need to do this yourself, because there are different modules that already does this:
passport-google-oauth
This makes it easy and assuming you are already using passport, this probably what you want. It is written by the author of passportjs. Just follow the example in it for OAuth 2.0 strategy. Note that you need to you add the right scopes when you are calling passport.authenticate('google', ...). This module when it gets the token, it will get the user profile, so you have to have one of the 3 scopes below:
passport.authenticate('google', { scope: [ // One of the next three `auth` scopes are needed.
'https://www.googleapis.com/auth/userinfo.profile',
'https://www.googleapis.com/auth/userinfo.email',
'https://www.googleapis.com/auth/plus.login',
'https://www.google.com/m8/feeds'
] }),
googleapis
This is module is officially supported by google and created by google employees. You can use it to authenticate, but sadly it doesn't support gData, which contains google contacts. You can check the example to see how you can get the token. You only need the m8/feeds scope with this module, no need for the other ones if you don't want to get the user profile.
gdata-js
This is a non-popular non-maintaining module, but it is more lightweight than the previous two modules. It might need a little polishing out of the box. I suggest also reading the source for understanding the api right.
Once you got the tokens, then you go for the slightly easier part, making the requests and getting the data.
If you read the docs, it's actually very easy. For example to get all contacts(almost all, it's paginated), you need to make a GET request to this url:
https://www.google.com/m8/feeds/contacts/default/full?alt=json&oauth_token=THE_ACCESS_TOKEN
Again there are many modules that can help you in this.
google-contacts
node-gdata
gdata-js Read the source to understand it's api. It's pretty easy actually:
var client = require('gdata-js')(GOOGLE_CLIENT_ID, GOOGLE_CLIENT_SECRET);
client.setToken({ access_token: accessToken, refresh_token: refreshToken });
client.getFeed('https://www.google.com/m8/feeds/contacts/default/full', function (err, result) { ... });
Google's official API for NodeJS doesn't support Contacts API, only the People API.
You can connect with Contacts API using the official googleapis library if you're already using it for other purposes by sending a request to the Contacts API after creating the auth client.
Given that you already have the access token of the user (e.g. if you generated it using Passport, here's the code:
const {google} = require("googleapis");
const authObj = new google.auth.OAuth2({
access_type: 'offline',
clientId: process.env.GOOGLE_ID,
clientSecret: process.env.GOOGLE_SECRET,
});
Refresh access token automatically before it expires
authObj.on('tokens', (tokens) => {
const access_token = tokens.access_token
if (tokens.refresh_token){
this.myTokens.refreshToken = tokens.refresh_token
// save refresh token in the database if it exists
}
this.myTokens.accessToken = tokens.access_token
// save new access token (tokens.access_token)
}
authObj.setCredentials({
access_token:this.myTokens.accessToken,
refresh_token:this.myTokens.refreshToken,
});
Make the request to Contacts API (Google uses Gaxios for making the requests to their APIs although it's not documented officially in googleapis, so just be aware that they might change remove/change the request call in the future without documenting it)
authObj.request({
headers:{
"GData-Version":3.0
},
params:{
"alt":"json",
//"q":"OPTIONAL SEARCH QUERY",
//"startindex":0
"orderby":"lastmodified",
"sortorder":"descending",
},
url: "https://www.google.com/m8/feeds/contacts/default/full"
}).then( response => {
console.log(response); // extracted contacts
});

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