clockworklabs/SpacetimeDB · error

Module defines http handler {} but does not export `{}`

Error message

Module defines http handler {} but does not export `{}`

What it means

Error "Module defines http handler {} but does not export `{}`" thrown in clockworklabs/SpacetimeDB.

Source

Thrown at crates/core/src/host/wasmtime/wasmtime_module.rs:850

    ) -> (module_host_actor::HttpHandlerExecuteResult, Option<TransactionOffset>) {
        let store = &mut self.store;
        prepare_store_for_call(store, budget);

        let call_type = op.call_type();
        let (request_source, response_sink) =
            store
                .data_mut()
                .start_funcall(op.name().clone(), op.request_bytes, op.timestamp, call_type);
        let request_body_source = store
            .data_mut()
            .create_extra_bytes_source(op.request_body_bytes)
            .expect("failed to register http handler request body");
        let response_body_sink = store.data_mut().create_bytes_sink();

        let Some(call_http_handler) = self.call_http_handler.as_ref() else {
            let res = module_host_actor::HttpHandlerExecuteResult {
                stats: ExecutionStats::default(),
                call_result: Err(anyhow::anyhow!(
                    "Module defines http handler {} but does not export `{}`",
                    op.name,
                    CALL_HTTP_HANDLER_DUNDER,
                )),
            };
            return (res, None);
        };

        let call_result = call_http_handler
            .call_async(
                &mut *store,
                (
                    op.id.0,
                    op.timestamp.to_micros_since_unix_epoch() as u64,
                    request_source.0,
                    request_body_source.0,
                    response_sink,
                    response_body_sink,

View on GitHub (pinned to 524b4487d9)

When it happens

Trigger: Thrown at crates/core/src/host/wasmtime/wasmtime_module.rs:850 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of clockworklabs/SpacetimeDB@524b4487d9 (2026-08-16). Data as JSON: /api/errors/6994922a0e03130a. Report an issue: GitHub.