SignedJwtAssertionCredentials on AppEngine doesn't recognize PEM key

Question

SignedJwtAssertionCredentials on appengine (with pycrypto 2.6) doesn\'t support the PKCS12 format, therefore I\'m trying to use PEM keys instead, as suggested everywhere..

Answer 1

Yeah, the error is hugely misleading. What you're doing is fine; just remove the header from the PEM file so that it begins with -----BEGIN PRIVATE KEY-----, or run the following command over it:

openssl pkcs8 -nocrypt -in privatekey.pem -passin pass:notasecret -topk8 -out pk.pem