Allow Vault configuration from VAULT_ADDR environment variable

[petems]

What are you seeing

The Vault address has to be provided within the Puppet code to use the lookup. It would be nicer if this was an optional parameter, and the Puppet agent could use the VAULT_ADDR environment variable to find the Vault address instead.

What behaviour did you expect instead

cat /etc/sysconfig/puppet
VAULT_ADDR=http://vault.example.com:8200

THen we dont have to specify

$d = Deferred('vault_lookup::lookup', ["secret/test"])

node default {
  notify { example :
    message => $d
  }
}

Output log

Any additional information you'd like to impart

[petems]

PR open! 👍