Parsing certificate (for Firebase JWT verification)

[jimmyff]

I'm attempting to verify Firebase JWT tokens in my cloud function (running on cloudrun). I'm following the guidelines here ( https://firebase.google.com/docs/auth/admin/verify-id-tokens#verify_id_tokens_using_a_third-party_jwt_library ) which say grab the public key here: https://www.googleapis.com/robot/v1/metadata/x509/securetoken@system.gserviceaccount.com

The JSON contains PEM certificates and I need to extract the public keys from them. Is there a way to use this package to parse the certificates so I can extract the Public Key to verify the JWT?

Thanks

Example Google PEM 8f43204a17915e8be7ccd7cb264df6ea383c49ab I'm trying to extract the public key from:

-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

[jimmyff]

I managed to solve my problem using the package:jose