Sume uploadFile with raw bytes needs a content type, or no request

If uploadFile from @sume-com/sdk throws contentType is required unless file is a Blob with a type, you passed raw bytes with no MIME type, and nothing was sent. The helper does not guess the type from the filename or from magic bytes. The error is a SumeUploadError with step set to create and status undefined, because no HTTP response exists yet.

Fix it in one of two ways: pass contentType explicitly, or pass a Blob or File whose type is non-empty. A blank or whitespace-only contentType counts as missing, and an explicit value wins over the Blob type.

Which input carries a type

The helper accepts a Blob, an ArrayBuffer or a Uint8Array. Only a Blob can bring its own type. The upload is the first of three calls described in the asset flow: reserve a URL, PUT the bytes, then complete.

Seeing the guard fire

This script needs no network. The client is built with a placeholder key because the guard throws before the client is used, so you can run it in a unit test.

import { createSumeClient, uploadFile, SumeUploadError } from "@sume-com/sdk";

const client = createSumeClient({ apiKey: "test-key" });
const bytes = new Uint8Array([137, 80, 78, 71]);

try {
  await uploadFile({ client, file: bytes });
} catch (error) {
  if (error instanceof SumeUploadError) {
    console.log(error.step, error.status, error.message);
  } else {
    throw error;
  }
}

// With a type the call proceeds to the network, so pass a real key to run it.
// await uploadFile({ client, file: bytes, contentType: "image/png" });

What to do in an upload service

• Take the MIME type from the user-facing upload, such as the multipart part header, and pass it through. Validate it against an allowlist first.
• Do not retry a step create failure with the same arguments. It is deterministic.
• Branch on error.step in logs so a missing type is not confused with a storage failure at put.
• Check the returned content_type against what you sent when the type matters downstream.