* Persist HCP management token from server config
We want to move away from injecting an initial management token into
Consul clusters linked to HCP. The reasoning is that by using a separate
class of token we can have more flexibility in terms of allowing HCP's
token to co-exist with the user's management token.
Down the line we can also more easily adjust the permissions attached to
HCP's token to limit it's scope.
With these changes, the cloud management token is like the initial
management token in that iit has the same global management policy and
if it is created it effectively bootstraps the ACL system.
* Update SDK and mock HCP server
The HCP management token will now be sent in a special field rather than
as Consul's "initial management" token configuration.
This commit also updates the mock HCP server to more accurately reflect
the behavior of the CCM backend.
* Refactor HCP bootstrapping logic and add tests
We want to allow users to link Consul clusters that already exist to
HCP. Existing clusters need care when bootstrapped by HCP, since we do
not want to do things like change ACL/TLS settings for a running
cluster.
Additional changes:
* Deconstruct MaybeBootstrap so that it can be tested. The HCP Go SDK
requires HTTPS to fetch a token from the Auth URL, even if the backend
server is mocked. By pulling the hcp.Client creation out we can modify
its TLS configuration in tests while keeping the secure behavior in
production code.
* Add light validation for data received/loaded.
* Sanitize initial_management token from received config, since HCP will
only ever use the CloudConfig.MangementToken.
* Add changelog entry
Previously, we'd begin a session with the xDS concurrency limiter
regardless of whether the proxy was registered in the catalog or in
the server's local agent state.
This caused problems for users who run `consul connect envoy` directly
against a server rather than a client agent, as the server's locally
registered proxies wouldn't be included in the limiter's capacity.
Now, the `ConfigSource` is responsible for beginning the session and we
only do so for services in the catalog.
Fixes: https://github.com/hashicorp/consul/issues/15753
