Struct Envelope 

pub struct Envelope<'a> { /* private fields */ }

One JSON-RPC message, borrowed from the frame buffer.

kind is the validated shape. The other fields are what the sender wrote, kept as they arrived — a method is Some on a request and a notification and None on a reply, and the two are the only way to tell those apart without consulting kind, which is why kind exists.

No PartialEq, for the reason on WireError.

Implementations

impl<'a> Envelope<'a>

pub const fn kind(&self) -> MessageKind

The shape this message was decoded as.

pub const fn id(&self) -> Option<&WireId<'a>>

The id, absent on a notification.

By reference: an id whose text had to be unescaped owns a String, and returning it by value would clone that on every read. The common unescaped case borrows, so a clone there would be a refcount bump on nothing — either way the caller only wanted to look at it.

pub const fn method(&self) -> Option<&Method<'a>>

The method, absent on a reply.

pub fn method_str(&self) -> Option<&str>

The method as a plain string, whichever arm of the Cow it is.

pub const fn params(&self) -> Option<&'a RawValue>

The params, still undecoded.

Borrowed raw JSON on purpose: the concrete type depends on the method and the negotiated revision, and neither is known until after routing. Decoding here would mean decoding every frame’s params even for methods that are about to be refused for not existing.

pub const fn outcome(&self) -> Option<&Outcome<'a>>

The reply half, present only on a Result or an Error.

pub const fn expects_reply(&self) -> bool

Whether a reply is expected.

pub fn routeable(&self) -> Option<(&Method<'a>, Option<&WireId<'a>>)>

The method and id together, for the router.

Returns None for a reply shape, which has no method to route.

Trait Implementations

impl<'a> Clone for Envelope<'a>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Debug for Envelope<'a>

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

Formats the value using the given formatter.