The `ReconcileProviders` function was incorrectly including the default
inline provider (`access.teleport.dev`) in the lists of added, updated,
and removed providers.
The inline provider is a special case managed directly by the access
controller and does not correspond to a separate, reloadable resource.
Including it in the change lists could lead to errors when attempting
to perform lifecycle operations on it.
This commit modifies the reconciliation logic to explicitly ignore the
inline provider when calculating changes. This ensures that only
external, reloadable providers are reported as changed, preventing
incorrect lifecycle management.
The provider reconciliation logic did not correctly handle aliased provider configurations (e.g., using YAML anchors). When a provider config was aliased, the check for configuration equality would pass, causing the system to reuse the existing provider instance without rebuilding it, even if the underlying configuration had changed.
This change introduces a check to detect if the old and new provider configurations point to the same object in memory. If they are aliased, the provider is now always rebuilt to ensure it reflects the latest configuration. The optimization to reuse an existing provider based on deep equality is now only applied to non-aliased providers.
This commit introduces a reconciliation mechanism for handling configuration updates, significantly improving efficiency and resource management.
Previously, reloading the configuration would tear down and recreate all access providers from scratch, regardless of whether their individual configurations had changed. This was inefficient and could disrupt services.
The new `sdkaccess.ReconcileProviders` function now compares the old and new configurations to intelligently manage the provider lifecycle:
- Unchanged providers are kept.
- New providers are created.
- Providers removed from the config are closed and discarded.
- Providers with updated configurations are gracefully closed and recreated.
To support this, a `Close()` method has been added to the `Provider` interface.
A similar reconciliation logic has been applied to the client registration state in `state.RegisterClient`. This ensures that model registrations are accurately tracked when a client's configuration is updated, correctly handling added, removed, and unchanged models. Enhanced logging provides visibility into these operations.
