Struct SubprotocolDescriptor 

pub struct SubprotocolDescriptor {
    pub id: u16,
    pub name: String,
    pub version: SubprotocolVersion,
    pub min_compatible: SubprotocolVersion,
    pub handler_present: bool,
}

Metadata describing a registered subprotocol.

Fields

id: u16

Unique protocol ID (from Net header subprotocol_id field).

name: String

Human-readable name (e.g., “causal”, “migration”, “vendor-x-inference”).

version: SubprotocolVersion

Version of this handler.

min_compatible: SubprotocolVersion

Minimum compatible version accepted from peers.

handler_present: bool

Whether this node can process packets for this subprotocol (false = opaque forwarding only, no local handler).

Implementations

impl SubprotocolDescriptor

pub fn new( id: u16, name: impl Into<String>, version: SubprotocolVersion, ) -> Self

Create a new descriptor.

pub fn with_min_compatible(self, min: SubprotocolVersion) -> Self

Set the minimum compatible version.

Enforces the wire-format invariant min_compatible <= version. Allowing min_compatible > version would break is_compatible_with’s contract — every honest peer computes local.version.satisfies(other.min_compatible), which silently fails for any version of local once other.min_compatible > other.version. On the wire-format side that enables a phantom-incompatibility DoS where a peer advertises min_compatible=255.255 against version=1.0 and unilaterally evicts the subprotocol from negotiation. The constructor (new) initializes min_compatible = version so the invariant holds by default; this setter clamps min to self.version if a caller passes a higher value.

pub fn forwarding_only(self) -> Self

Mark as forwarding-only (no local handler).

pub fn is_compatible_with(&self, other: &Self) -> bool

Check if two descriptors are version-compatible.

Both sides must satisfy the other’s minimum requirement.

pub fn capability_tag(&self) -> String

Capability tag for this subprotocol (e.g., “subprotocol:0x0400”).

Trait Implementations

impl Clone for SubprotocolDescriptor

fn clone(&self) -> SubprotocolDescriptor

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SubprotocolDescriptor

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

Formats the value using the given formatter.

impl Display for SubprotocolDescriptor

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

Formats the value using the given formatter.