Struct SubscribeNamespaceStateMachine 

pub struct SubscribeNamespaceStateMachine {
    state: SubscribeNamespaceState,
}

State machine for SUBSCRIBE_NAMESPACE flow. Idle -> Pending -> Active -> Done.

Fields

state: SubscribeNamespaceState

Implementations

impl SubscribeNamespaceStateMachine

pub fn new() -> Self

Creates a new machine in SubscribeNamespaceState::Idle.

pub fn state(&self) -> SubscribeNamespaceState

Returns the current state of the subscribe-namespace flow.

pub fn on_subscribe_namespace_sent(&mut self) -> Result<(), NamespaceError>

Idle -> Pending.

pub fn on_subscribe_namespace_ok(&mut self) -> Result<(), NamespaceError>

Pending -> Active.

pub fn on_subscribe_namespace_error(&mut self) -> Result<(), NamespaceError>

Pending -> Done.

pub fn on_request_cancelled(&mut self) -> Result<(), NamespaceError>

Pending | Active -> Done, Done -> Done (this subscription’s stream was closed).

Draft-16 has no UNSUBSCRIBE_NAMESPACE. The subscription is withdrawn by ending the stream it was made on — Section 6.1: “A SUBSCRIBE_NAMESPACE can be cancelled by closing the stream with either a FIN or RESET_STREAM.” Either form is a withdrawal, so both arrive here.

Pending is accepted because the stream is open from the SUBSCRIBE_NAMESPACE that opened it, and the sentence asks for nothing more: a namespace subscription can be withdrawn before it is ever answered.

Idle is refused, on the other half of the same sentence: nothing has been written, so there is no stream to close. Done stays Done — a subscription that has already ended is still carried on a stream, and closing that stream afterwards is the ordinary end rather than a fault.

pub fn on_subscribe_namespace_received(&mut self) -> Result<(), NamespaceError>

Idle -> Pending (the peer opened a stream with a SUBSCRIBE_NAMESPACE on it).

The mirror of on_subscribe_namespace_sent, named for the direction it runs in rather than sharing that one: the state edges coincide, so a mis-dispatch would succeed silently instead of naming the wrong event in an InvalidTransition.

pub fn on_subscribe_namespace_ok_sent(&mut self) -> Result<(), NamespaceError>

Pending -> Active (this endpoint answered the peer’s request with a REQUEST_OK).

pub fn on_subscribe_namespace_error_sent( &mut self, ) -> Result<(), NamespaceError>

Pending -> Done (this endpoint refused the peer’s request).

Trait Implementations

impl Default for SubscribeNamespaceStateMachine

fn default() -> Self

Returns the “default value” for a type.