Add option to take credentials from kubernetes secrets

[runitmisra]

Many credentials are being used in the deployments like username and password/identity secrets for peers, orderers, CAs, etc. Along with passing these values as plaintext in helm values file, there should be an option to read these values from kubernetes secrets (like many vendor helm charts offer).

The creation of these secrets is up to the user, weather they create them manually or via some operator like External Secrets Operator.

This will directly help towards the "Manage secrets with secrets management services like Vault, AWS Secrets manager, etc" feature goal.

Example:
The Values file will look something like this:

identity_name: xyz
identity_secret: abc
# Name of the secret resource to take the above two values from. The keys have to be exactly same as above.
identityCredsFromSecret: identity_secret #<--- This is the name of the secret resource where the identity_name and identity_secret is mentioned

[tittuvarghese]

@runitmisra Please proceed with the required changes and make a pull request. Also, update the relevant read-me and sample scripts.

May be we should be having a mechanism to setup required secrets in the start of setup. Or possible auto secret generation.

[jithindevasia]

@runitmisra Use a single secret for all identity registration under a CA rather than creating individual secrets for every identities. Otherwise we will end-up with 100+ secrets for the TLSCA.

[tittuvarghese]

@jithindevasia can't we dynamically generate the secrets and it's value. (From a security standpoint let all identities be using a unique secret)

[jithindevasia]

@jithindevasia can't we dynamically generate the secrets and it's value. (From a security standpoint let all identities be using a unique secret)

Managing/Creating secrets from falcon will lead us to use any cli actions like kubectl or something which will be platform dependent then. I prefer to leave the secret creation/management outside falcon. So people can have their own way to manage secrets.