Use path location for keys instead of parameter values

[sverraest]

Is there a way to give a location to a path on the server for the private.pem and public.pem keys instead of having to include them in the parameters.yml file?

[picodexter]

Right now there is no way to do that right out of the box, but you could add a key transformer service which takes the key value and transforms it based on certain criteria (e.g. if the value starts with "file:" you could recognize the rest of the value as a path).

The key transformers are loaded by the pcdx_parameter_encryption.encryption.key.resolver service, so you just have to override that service definition in order to load your own one.

Btw this is an issue for the main bundle PcdxParameterEncryptionBundle, but I do get that it especially makes sense in this particular bundle.