Struct CapabilityRegistry 

pub struct CapabilityRegistry { /* private fields */ }

Per-node registry that owns capability instances, generates the local advertisement, and stores the most recently negotiated value for each capability.

Implementations

impl CapabilityRegistry

pub fn new() -> Self

Construct an empty registry.

pub fn register<C: Capability>(&mut self, cap: C)

Register a capability. Re-registering a capability with the same name replaces the previous entry; the cluster layer never registers two caps with the same name, so this only matters for tests.

pub fn local_advertise(&self) -> CapabilityAd

Build the advertisement to ship to peers.

pub fn negotiate(&self, peer_ad: &CapabilityAd) -> NegotiatedCapabilities

Resolve peer_ad against the locally registered caps.

Returns a NegotiatedCapabilities keyed by capability name. The registry also caches each negotiated value so later calls to CapabilityRegistry::current reflect the most recent negotiation.

Capabilities present in peer_ad but not registered locally fall through silently: the negotiator can only pick a value for capabilities both sides know about.

pub fn current<C: Capability>(&self, name: &str) -> Option<C::Value>

Return the currently active value for the named capability, decoded with the registered cap’s Capability::decode_value.

Returns None when no capability with that name is registered, when the type parameter C does not match the registered cap, or when the stored bytes fail to decode (which would be a registry bug).

Before any negotiation has happened the floor value (lowest-preference local value) is returned.

pub fn len(&self) -> usize

Number of registered capabilities. Useful in tests and diagnostics.

pub fn is_empty(&self) -> bool

True when no capabilities have been registered.

Trait Implementations

impl Debug for CapabilityRegistry

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for CapabilityRegistry

fn default() -> Self

Returns the “default value” for a type.