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TypeError: undefined is not a constructor (evaluating 'new Headers({ ... , ... })')

See original GitHub issue

“react”: “16.0.0-alpha.3”, “react-native”: “0.44.0”, “react-native-fcm”: “^10.0.3”,

Running on iPhone6 OS v10.2.1

I am able to receive remote notifications when using the Firebase console cloud messaging. However, I am unable to invoke the messages manually using the ios example code(firebaseClient.js)

let headers = new Headers({
          "Content-Type": "application/json",
          "Authorization": "key=" + FirebaseConstants.KEY
  	});```

Issue Analytics

State:
Created 6 years ago
Comments:13 (5 by maintainers)

Top GitHub Comments

1reaction

atpunkcommented, Dec 15, 2017

Issue Solved.

I was unclear on which key to use in the FirebaseConstants.js

I was using my Web API Key when I actually needed my Project Settings->Cloud Messaging->Server Key.

0reactions

evollucommented, Dec 13, 2017

Header is not a constructor so you need to fix your code. check fetch library document
as you can see, you are getting 401 error from firebase so no notification.

nothing to do with versions

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