How to use Apple's new .p8 certificate for APNs in firebase console

I was able to do this by selecting "All" located under the "Keys" header from the left column

Then I clicked the plus button in the top right corner to add a new key

Enter a name for your key and check "APNs"

Then scroll down and select Continue. You will then be brought to a screen presenting you with the option to download your .p8 now or later. In my case, I was presented with a warning that it could only be downloaded once so keep the file safe.

Apple have recently made new changes in APNs and now apple insist us to use "Token Based Authentication" instead of the traditional ways which we are using for push notification.

So does not need to worry about their expiration and this p8 certificates are for both development and production so again no need to generate 2 separate certificate for each mode.

To generate p8 just go to your developer account and select this option "Apple Push Notification Authentication Key (Sandbox & Production)"

Then will generate directly p8 file.

I hope this will solve your issue.

Read this new APNs changes from apple: https://developer.apple.com/videos/play/wwdc2016/724/

Also you can read this: https://developer.apple.com/library/prerelease/content/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/Chapters/APNsProviderAPI.html