Module contract 

The one request contract, independent of transport.

A request is a method id, a Caller, JSON params, and a JSON result or a ServiceError. The local transport (framed JSON lines over a current-user-only socket or pipe) is an adapter onto it; a later transport maps onto the same types. This module holds no I/O.

• Caller says who is asking: a local app (OS-verified peer) or a device (id and scopes).
• MethodTable is the single source of method policy (MethodPolicy); the local Allowlist is derived from it (MethodTable::allowlist) and MethodTable::authorize answers for any caller.
• Handler, CallContext and Emit are the serving side.
• status_for_code maps an error code to an HTTP-style status for transports that need one.

Structs

CallContext

What a handler knows about the request it is serving.

MethodPolicy

Policy for one method id: which local apps may call it and which scopes a device needs.

MethodTable

Every method of a service with its policy: the one source the local allowlist and a remote route table are both derived from. ping is never listed and always allowed.

Enums

Caller

Who is making a request.

TableError

Why a method id or its policy was refused at table construction.

Transport

Which transports a method is reachable on.

Constants

ROLE_SCOPE_PREFIX

A scope that names a role instead of a capability: role:<name>, for example role:operator.

Traits

Handler

Functions

role_of

The one role among scopes: Some only when exactly one scope is a role scope with a non-empty name. Two roles, or none, give None, so an ambiguous device never gets a role by the luck of an iteration order.

role_scope

The scope that grants role.

status_for_code

Status for a code; None when the table does not know it.

status_for_error

Status for an error: the table, else 503 when retryable, else 500.

validate_method_id

A method id must be a plain name: non-empty, no glob characters, whitespace, control characters, /, % or #.

Type Aliases

Emit

Sends an event frame for the request being handled.

Scope

A capability a device holds (from enrolment). A plain label compared for equality.