messages_without_schema

messages_without_schema lists the messages the document describes with no payload schema, for a check to fail on.

A message without a schema documents its channel but not its shape, and a client generator has no type to produce from it. build_spec logs one warning per gap when it builds the document; this method returns the same list as component names. A test or a release check asserts on it. Messages whose bytes are their own format, on a byte lane, are left out: they have no schema by design. On the attribute path a gap is a message type without a JsonSchema derive. A subscriber(..) registration has one only after undocumented. The example runs with cargo test --example asyncapi_schemas --features macros,memory,asyncapi.

Example

Macros

examples/asyncapi_schemas.rs

/// An audit record another team publishes, with no schema shipped for it.
#[derive(Debug, Deserialize)]
struct AuditRecord {
    action: String,
}

#[subscriber("audit")]
async fn record(entry: &AuditRecord) -> HandlerOutcome {
    tracing::info!(action = %entry.action, "audited");
    HandlerOutcome::ack()
}

/// The release check: every message in the document has a schema, or the check names the ones
/// that do not.
fn check_schemas(spec: &Spec) -> Result<(), String> {
    match spec.messages_without_schema().as_slice() {
        [] => Ok(()),
        gaps => Err(format!("no payload schema for {}", gaps.join(", "))),
    }
}

Manual

examples/manual/asyncapi_schemas.rs

/// An audit record another team publishes, with no schema shipped for it.
#[derive(Debug, Deserialize)]
struct AuditRecord {
    action: String,
}

struct Record;

impl Handle<AuditRecord> for Record {
    fn handle(
        &self,
        entry: &AuditRecord,
        _outs: &(),
        _ctx: &mut Context<'_>,
    ) -> impl Future<Output = Result<(), HandlerOutcome>> {
        tracing::info!(action = %entry.action, "audited");
        ready(Ok(()))
    }
}

/// The release check: every message in the document has a schema, or the check names the ones
/// that do not.
fn check_schemas(spec: &Spec) -> Result<(), String> {
    match spec.messages_without_schema().as_slice() {
        [] => Ok(()),
        gaps => Err(format!("no payload schema for {}", gaps.join(", "))),
    }
}