After a more detailed analysis of this feature, the approach taken in
PR #12449 was found to be not ideal due to poor UX (users are
responsible for setting the entity alias they would like to use) and
issues around jobs potentially masquerading itself as another Vault
entity.
Move some common Vault API data struct decoding out of the Vault client
so it can be reused in other situations.
Make Vault job validation its own function so it's easier to expand it.
Rename the `Job.VaultPolicies` method to just `Job.Vault` since it
returns the full Vault block, not just their policies.
Set `ChangeMode` on `Vault.Canonicalize`.
Add some missing tests.
Allows specifying an entity alias that will be used by Nomad when
deriving the task Vault token.
An entity alias assigns an indentity to a token, allowing better control
and management of Vault clients since all tokens with the same indentity
alias will now be considered the same client. This helps track Nomad
activity in Vault's audit logs and better control over Vault billing.
Add support for a new Nomad server configuration to define a default
entity alias to be used when deriving Vault tokens. This default value
will be used if the task doesn't have an entity alias defined.
Establishing leadership should be very fast and never make external API
calls.
This fixes a situation where there is a long backlog of Vault tokens to
be revoked on when leadership is gained. In such case, revoking the
tokens will significantly slow down leadership establishment and slow
down processing. Worse, the revocation call does not honor leadership
`stopCh` signals, so it will not stop when the leader loses leadership.
Token revocation
Remove from the statestore
Revoke tokens
Don't error when Vault is disabled as this could cause issue if the operator ever goes from enabled to disabled
update server interface to allow enable/disable and config loading
test the new functions
Leader revoke
Use active
