Struct Envelope 

pub struct Envelope {

    pub arcp: String,
    pub id: MessageId,
    pub timestamp: DateTime<Utc>,
    pub source: Option<String>,
    pub target: Option<String>,
    pub session_id: Option<SessionId>,
    pub job_id: Option<JobId>,
    pub stream_id: Option<StreamId>,
    pub subscription_id: Option<SubscriptionId>,
    pub trace_id: Option<TraceId>,
    pub span_id: Option<SpanId>,
    pub parent_span_id: Option<SpanId>,
    pub correlation_id: Option<MessageId>,
    pub causation_id: Option<MessageId>,
    pub idempotency_key: Option<IdempotencyKey>,
    pub priority: Priority,
    pub extensions: Option<Value>,
    pub event_seq: Option<u64>,
    pub payload: MessageType,
}

Typed protocol envelope (RFC §6.1).

payload is #[serde(flatten)]-embedded so the wire form is flat:

{
  "arcp": "1.1", "id": "msg_...", "timestamp": "...",
  "type": "ping", "payload": {}
}

Fields

arcp: String

Protocol version understood by the sender.

id: MessageId

Globally unique message id; transport-level idempotency key (RFC §6.4).

timestamp: DateTime<Utc>

Sender timestamp in RFC 3339 format.

source: Option<String>

Logical sender id (e.g. client / runtime / agent name).

target: Option<String>

Logical recipient id.

session_id: Option<SessionId>

Required once a session exists.

job_id: Option<JobId>

Required for durable job events.

stream_id: Option<StreamId>

Required for stream events.

subscription_id: Option<SubscriptionId>

Required for subscription delivery.

trace_id: Option<TraceId>

Stable id for one user-visible request or workflow (recommended).

span_id: Option<SpanId>

Span id for the current operation (recommended).

parent_span_id: Option<SpanId>

Parent span id when this message is part of a trace tree.

correlation_id: Option<MessageId>

Id of the command or request this message answers.

causation_id: Option<MessageId>

Id of the message that directly caused this message.

idempotency_key: Option<IdempotencyKey>

Logical idempotency key for the command intent (RFC §6.4).

priority: Priority

Message priority. Default normal.

extensions: Option<Value>

Object of namespaced extension fields (RFC §21).

event_seq: Option<u64>

Strictly increasing per-session sequence number for countable events (ARCP v1.1 §6.5 / §6.6). Stamped by the runtime writer on every envelope where MessageType::is_countable_event is true; absent on session-control envelopes and on locally constructed envelopes that have not yet been emitted by a runtime writer.

payload: MessageType

Type-specific body. Flattened so type and payload appear at the envelope level on the wire.

Implementations

impl Envelope

pub fn new(payload: MessageType) -> Envelope

Construct a new envelope with the supplied payload, a freshly generated MessageId, the current UTC timestamp, the crate’s PROTOCOL_VERSION, and priority = normal.

pub fn into_raw(self) -> Result<RawEnvelope, ARCPError>

Convert to the untyped wire shape suitable for inspection / logging without re-deserialising.

Errors

Returns crate::error::ARCPError::Serialization if the envelope cannot be serialised (this should not happen for any value constructed by this crate).

Trait Implementations

impl Clone for Envelope

fn clone(&self) -> Envelope

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Envelope

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Envelope

fn deserialize<__D>( __deserializer: __D, ) -> Result<Envelope, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for Envelope

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for Envelope

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Envelope