ios – Unhandled Exception: PlatformException with calling Spotify authorization in Flutter app

I’m trying to make a simple Flutter application which has a user sign in to Spotify and aggregate listening activity, show stats, etc.

I’m having some trouble with the Spotify API. Every time I try launch the Spotify authorization URL I’m getting the following error message from Flutter.

[ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: PlatformException(Error, Error while launching https://accounts.spotify.com/authorize/?response_type=code&client_id=6b12ed8ef79648e88e6646d7f16f5a50&scope=user-read-private&redirect_uri=http://localhost:8888//callback, null, null)

Here’s what my code for getting the URL looks like.

Future<void> login(BuildContext context) async {
    await dotenv.load();

    final clientId = dotenv.env['SPOTIFY_CLIENT_ID'];
    final scopes = dotenv.env['SPOTIFY_SCOPES'];
    final redirectUri = dotenv.env['SPOTIFY_REDIRECT_URI'];
    final url = Uri.parse('https://accounts.spotify.com/authorize/'
        '?response_type=code'
        '&client_id=$clientId'
        '&scope=$scopes'
        '&redirect_uri=$redirectUri');

    // Launch the constructed URL using url_launcher
    await launchUrl(url);
  }

where my environment variables are

SPOTIFY_CLIENT_ID=6b12ed8ef79648e88e6646d7f16f5a50
SPOTIFY_SECRET_ID=...
SPOTIFY_REDIRECT_URI=http://localhost:8888//callback
SPOTIFY_SCOPES=user-read-private

(side note: is it fine to share my client ID? I’ve removed my secret ID)

I’ve messed around with the redirect URI to no avail. And I have double-checked that my redirect URI is the same as my Spotify developer platform.

The eventual goal is to get a successful login, get the user access token, and then navigate out of the web authorization page.

Thanks in advance for the help.