[bug]: type 'Null' is not a subtype of type 'String' in type cast

[kNoAPP]

Tip

A workaround was found by @ManishKiranagi that can be used in the interim:

Seems to be an issue with latest version of firebase tools
We are using previous version (13.30.0) now and it works
npm install -g firebase-tools@13.30.0

Is there an existing issue for this?

• I have searched the existing issues.

CLI Version

1.0.1

Firebase Tools version

13.31.0

Flutter Doctor Output

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    • Framework revision d8a9f9a52e (12 days ago), 2025-01-31 16:07:18 -0500
    • Engine revision 82bd5b7209
    • Dart version 3.6.2
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    • Java version Java(TM) SE Runtime Environment (build 17.0.12+8-LTS-286)
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• No issues found!

Description

The CLI throws an error if I run the command:

dart pub global run flutterfire_cli:flutterfire configure --yes --platforms android,ios,web --project hylist-dev-4 --android-package-name com.knoban.hylist --ios-bundle-id com.knoban.hylist --web-app-id 1:XXX:web:072855a5f24c99fe661eca --macos-bundle-id com.knoban.hylist --windows-app-id com.knoban.hylist

The error produced is:

25l⠋ Fetching available Firebase projects...           
i Found 1 Firebase projects. Selecting project hylist-dev-4.                    
25hi Selected platforms: android,ios,web
25l⠋ Fetching registered android Firebase apps for project hylist-dev-4                        
i Firebase ios app com.knoban.hylist registered.                                
25h25l⠋ Fetching registered web Firebase apps for project hylist-dev-4                
⠙ Fetching registered web Firebase apps for project hylist-dev-4                           
i Firebase web app 1:XXX:web:072855a5f24c99fe661eca registered.       
type 'Null' is not a subtype of type 'String' in type cast
25h
Error: Process completed with exit code 1.

Steps to reproduce

Run the command (or similar):

dart pub global run flutterfire_cli:flutterfire configure --yes --platforms android,ios,web --project hylist-dev-4 --android-package-name com.knoban.hylist --ios-bundle-id com.knoban.hylist --web-app-id 1:XXX:web:072855a5f24c99fe661eca --macos-bundle-id com.knoban.hylist --windows-app-id com.knoban.hylist

Expected behavior

Instead of exiting with an error:

type 'Null' is not a subtype of type 'String' in type cast
25h
Error: Process completed with exit code 1.

I expect it to succeed with:

Firebase configuration file lib/firebase_options.dart generated successfully with the following Firebase apps:

Platform  Firebase App Id
web       1:XXX:web:072855a5f24c99fe661eca
android   1:XXX:android:b9d3c9d71d3ab9b2661eca
ios       1:XXX:ios:723151eb48970ac8661eca

Learn more about using this file and next steps from the documentation:
 > https://firebase.google.com/docs/flutter/setup

Screenshots

No response

Additional context and comments

I have redacted the web id with an XXX. Probably overkill, but the full version is a valid web id.

This error began occurring in my GitHub Actions runner today with no change to the workflow file, any dependencies, or changes to the Firebase project. The workflow is always set up to use latest Firebase tools and v1.0.1 FlutterFire CLI. It was working just 24h ago.

[RicharC293]

Same issue here

[ManishKiranagi]

I am getting same issue. It was working yesterday

i Firebase web app 1:XXX:web:XXX registered.
25htype 'Null' is not a subtype of type 'String' in type cast

[hhparekh]

Same Issue here

[ManishKiranagi]

Seems to be an issue with latest version of firebase tools
We are using previous version (13.30.0) now and it works
npm install -g firebase-tools@13.30.0

[kNoAPP]

Seems to be an issue with latest version of firebase tools We are using previous version (13.30.0) now and it works npm install -g firebase-tools@13.30.0

Confirming this works on my end too. I have added a tip to the issue for randos to quickly find and apply your workaround. Thank you!

[matheuscsant]

Seems to be an issue with latest version of firebase tools We are using previous version (13.30.0) now and it works npm install -g firebase-tools@13.30.0

This solved for me, thanks!!

[Abdulazeez-Raja]

same issue

[Abdulazeez-Raja]

Seems to be an issue with latest version of firebase tools We are using previous version (13.30.0) now and it works npm install -g firebase-tools@13.30.0

this works for me

[SleepySquash]

Seems to be coming from the convertConfigToOptions() method in firebase_dart_options.dart for the Web platform (other platforms work flawlessly). The RegExp here seems to expect the appSdkConfig.fileContents to be firebase.initializeApp({ ... }), yet the actual contents are just the { ... } part without the method:

{
  "projectId": "...",
  "appId": "...",
  "storageBucket": "...",
  "locationId": "...",
  "apiKey": "...",
  "authDomain": "...",
  "messagingSenderId": "...",
  "measurementId": "..."
}

Or something? I guess a fix for the issue is to check both the RegExp and, if empty, to try parse the contents directly without the RegExp?

[ndtkhang]

Seems to be an issue with latest version of firebase tools We are using previous version (13.30.0) now and it works npm install -g firebase-tools@13.30.0

LETS GO IT'S FIXED, THANK YOU SO MUCH

[innoalubzi]

Seems to be an issue with latest version of firebase tools We are using previous version (13.30.0) now and it works npm install -g firebase-tools@13.30.0

This worked for me too. Thanks