Function uploadViaMultipart

apps/sim/lib/uploads/client/direct-upload.ts:331–527

(
  opts: MultipartUploadOptions
)

}

const uploadViaMultipart = async (
  opts: MultipartUploadOptions
): Promise<{ key: string; path: string }> => {
  const { file, workspaceId, context, workflowId, executionId, signal, onProgress } = opts

  // boundary-raw-fetch: multipart upload control plane uses action query strings; client lifecycle (initiate/get-part-urls/complete/abort) is sequenced manually and not modeled by a single contract
  const initiateResponse = await fetch('/api/files/multipart?action=initiate', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      fileName: file.name,
      contentType: getFileContentType(file),
      fileSize: file.size,
      workspaceId,
      context,
      ...(workflowId ? { workflowId } : {}),
      ...(executionId ? { executionId } : {}),
    }),
    signal,
  })

  if (!initiateResponse.ok) {
    let errorBody: { error?: string } | null = null
    try {
      errorBody = (await initiateResponse.clone().json()) as { error?: string }
    } catch {}
    if (
      initiateResponse.status === 400 &&
      typeof errorBody?.error === 'string' &&
      errorBody.error.toLowerCase().includes('cloud storage')
    ) {
      throw new DirectUploadError(
        'Server signaled fallback to API upload',
        'FALLBACK_REQUIRED',
        errorBody
      )
    }
    throw new DirectUploadError(
      `Failed to initiate multipart upload: ${initiateResponse.statusText}`,
      'MULTIPART_ERROR',
      undefined,
      initiateResponse.status
    )
  }

  const { key, uploadToken } = (await initiateResponse.json()) as {
    uploadId: string
    key: string
    uploadToken: string
  }

  const numParts = Math.ceil(file.size / CHUNK_SIZE)
  const partNumbers = Array.from({ length: numParts }, (_, i) => i + 1)

  const abortMultipart = async () => {
    try {
      // boundary-raw-fetch: fire-and-forget abort during multipart cleanup; intentionally avoids contract response parsing so cleanup cannot mask the original error
      await fetch('/api/files/multipart?action=abort', {