secretOrPrivateKey must be an asymmetric key when using RS256

[jdutheil]

• Operating System version: Ubuntu 22.10
• Firebase SDK version: 11.3.0
• Firebase Product: auth
• Node.js version: 16.13.2
• NPM version: 8.19.2

[REQUIRED] Step 3: Describe the problem

I am using Firebase-Admin on a NestJs API, build with NX ; my API is using Admin SDK to create and manage users. For that, I am using the method auth.createUser({email, password}), but Firebase throws an error, ONLY FOR THE FIRST CALL :

secretOrPrivateKey must be an asymmetric key when using RS256

I know my private key is readed right, and most of all, only the first call to createUser returns error ; other calls are working great.. So I ended up putting a call with fake datas right after the initialization of Firebase, to be able to use it in other parts of my app, but it doesn't seem so terrible..! I can't find any other people having the same issue, really weird.

Any idea ?

[luizfilho]

I was stuck in this problem, and the solution for me was generate de key using the key size as 2048 with algorithm:RS256

[karim-goubba]

I have the same error on simple nodejs code, but it happens for all the calls for me not only the first one. Any solution ? @luizfilho can you please explain where do you generate the key ? i'm doing it from firebase console and it's not giving the option to configure the key.

[luizfilho]

Wait, do you want generate a jsonwebtoken ? Just to check if we are in same page.

[diegosantosouza]

I have the same problem, entered the private-key and other information as env.
when I try to send message the error occurs.
Log: error: Unable to store a new push token secretOrPrivateKey must be an asymmetric key when using RS256
`
import admin from 'firebase-admin'

const {
FIREBASE_PROJECT_ID = '',
FIREBASE_PRIVATE_KEY = '',
FIREBASE_CLIENT_EMAIL = '',
} = process.env

class Firebase {
public init() {
return admin.initializeApp({
credential: admin.credential.cert({
projectId: FIREBASE_PROJECT_ID,
clientEmail: FIREBASE_CLIENT_EMAIL,
privateKey: FIREBASE_PRIVATE_KEY,
}),
})
}
}

export default Firebase
`

[diegosantosouza]

I solved it as follows

import admin from 'firebase-admin'

const {
  FIREBASE_PROJECT_ID = '',
  FIREBASE_PRIVATE_KEY = '',
  FIREBASE_CLIENT_EMAIL = '',
} = process.env

class Firebase {
  public init() {
    return admin.initializeApp({
      credential: admin.credential.cert({
        projectId: FIREBASE_PROJECT_ID,
        clientEmail: FIREBASE_CLIENT_EMAIL,
        privateKey: FIREBASE_PRIVATE_KEY.replace(/\\n/g, '\n'),
      }),
    })
  }
}

export default Firebase

my env :
FIREBASE_PRIVATE_KEY=-----BEGIN PRIVATE KEY-----\n<YOUR_PRIVATE_KEY>\n-----END PRIVATE KEY-----\n

the private key I used exactly as in the example, without quotes.

[luizfilho]

Perfect! In my case I put the key in a file, and I read the file to use it, to avoid the problem of \n.
Anyway, thanks for share.

[Yagelazuo]

@diegosantosouza you just pasted the service account json file in the .env File ?

[diegosantosouza]

@diegosantosouza you just pasted the service account json file in the .env File ?

firebase does not need all the information contained in the json file, only [projectId, clientEmail, privateKey]. you can use it as an environment variable to put your project into production without exposing the json file in your repository.

[karim-goubba]

Still the same error for me. Here's my code:
`
const admin = require("firebase-admin");
require('dotenv').config();

admin.initializeApp({
credential: admin.credential.cert({
projectId: process.env.FIREBASE_PROJECT_ID,
clientEmail: process.env.FIREBASE_CLIENT_EMAIL,
privateKey: process.env.FIREBASE_PRIVATE_KEY.replace(/\n/g, "\n"),
}),
});

admin.auth().getUser("kFC1nrE51YSIDdwY9gYWvyZxKtX2");
`
And in my env file:

Still getting the same error : secretOrPrivateKey must be an asymmetric key when using RS256

[lahirumaramba]

Since the original issue was encountered in NestJs API, built with NX, @jdutheil: does replacing the /n per #2051 (comment) (privateKey: FIREBASE_PRIVATE_KEY.replace(/\\n/g, '\n'),)work for you?

If not, could you provide us with a minimal repro or a complete code sample to reproduce the issue in NestJs API? Thanks.

[Yagelazuo]

It is an ubuntu problem probably

[focafull]

I have the same problem and none of the suggestions above worked for me

[Yagelazuo]

@jdutheil Hey, I have the same problem and I am using Ubuntu too, What I discovered is that if I run the same server on a different system (I ran it on mac) it works, This leads me to believe it has something to do with the ubuntu operating system