Trait EventSchema 

pub trait EventSchema:
    Send
    + Sync
    + Sized
    + 'static {
    const FULL_NAME: &'static str;
    const TIER: Tier;
    const DEFAULT_SEV: Severity;
    const FIELDS: &'static [FieldMeta];
    const SCHEMA_HASH: u64;
    const SPANS_PAIRED_WITH: Option<&'static str> = None;

    // Required methods
    fn encode_payload(&self, buf: &mut BytesMut);
    fn project(&self, env: &mut ObsEnvelope);

    // Provided method
    fn project_metrics(&self, sink: &mut dyn MetricEmitter) { ... }
}

Trait implemented by every Obs* event type.

Codegen emits one impl per .proto message or #[derive(Event)] struct. Sinks consume the object-safe sibling crate::registry::EventSchemaErased; this trait is for the monomorphised emit path.

Required Associated Constants

const FULL_NAME: &'static str

Fully qualified event name (myapp.v1.ObsXxx).

const TIER: Tier

Tier the schema declares.

const DEFAULT_SEV: Severity

Default severity the schema declares.

const FIELDS: &'static [FieldMeta]

Per-field metadata table.

const SCHEMA_HASH: u64

First 8 bytes of BLAKE3 over the canonical descriptor; baked at build time. See spec 10 § 6 + spec 12 § 3.5.

Provided Associated Constants

const SPANS_PAIRED_WITH: Option<&'static str> = None

When this event participates in a Started/Completed pair, the schema’s full name of its sibling event. The OTLP trace sink matches paired events on this constant rather than suffix sniffing. Schemas that are not paired return None. Spec 20 § 2.5 B / spec 93 P1-7.

Required Methods

fn encode_payload(&self, buf: &mut BytesMut)

Encode this event’s payload using buffa’s encoder into a reused buffer. The codegen impl forwards to buffa::Message::encode.

fn project(&self, env: &mut ObsEnvelope)

Project labels and lift trace/span ids onto the envelope. Generated; never hand-written. See spec 11 pipeline § 4.1.

Provided Methods

fn project_metrics(&self, sink: &mut dyn MetricEmitter)

For MEASUREMENT-annotated fields, emit metric data points. Phase-1 default impl is a no-op so MEASUREMENT-bearing schemas authored in Phase 1 do not error in metric sinks; Phase 2 codegen overrides this. Spec 12 § 3.2.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors