Struct Envelope 

pub struct Envelope<T> {
    pub v: u32,
    pub id: String,
    pub device_id: String,
    pub sent_at: DateTime<Utc>,
    pub reply_to: Option<String>,
    pub body: T,
}

One decoded frame: the invariant header, and the typed body.

Fields

v: u32

id: String

The request id. Doubles as the idempotency key — see super::idempotency.

device_id: String

sent_at: DateTime<Utc>

reply_to: Option<String>

The id of the request this frame answers, or None for an unsolicited one.

body: T

Implementations

impl<T> Envelope<T>

pub fn new( id: impl Into<String>, device_id: impl Into<String>, sent_at: DateTime<Utc>, body: T, ) -> Self

Build a frame to send. sent_at is taken from the caller rather than the clock so that tests and the golden fixtures are not time-dependent. A frame stamped with the newest version this build speaks.

Right for a peer known to be current, and for tests. A connection that has negotiated down must use Self::at_version instead.

pub fn at_version( version: u32, id: impl Into<String>, device_id: impl Into<String>, sent_at: DateTime<Utc>, body: T, ) -> Self

A frame stamped with a specific version.

Why this is not just new. Once two versions exist, the version a session speaks is the one it negotiated, not the one this build prefers. A v2 daemon that stamped 2 on every frame after agreeing to speak 1 would have every frame refused by the peer that asked it to downgrade — which is the entire population of already-deployed peers.

pub fn in_reply_to(self, request_id: impl Into<String>) -> Self

Trait Implementations

impl<T: Clone> Clone for Envelope<T>

fn clone(&self) -> Envelope<T>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for Envelope<T>

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

Formats the value using the given formatter.

impl<T: PartialEq> PartialEq for Envelope<T>

fn eq(&self, other: &Envelope<T>) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<T: PartialEq> StructuralPartialEq for Envelope<T>