BerriAI/litellm · error · ValueError

file is required

Error message

file is required

What it means

The Bedrock create-file handler requires the multipart 'file' field; data.get('file') returned None, so there are no bytes to extract, name, and PUT to S3. This guard runs before purpose validation.

Source

Thrown at litellm/llms/bedrock/files/transformation.py:345

    ) -> str:
        """
        Get the complete S3 URL for the file upload request
        """
        request_params: Final = merge_bedrock_aws_request_params(litellm_params, optional_params)
        bucket_name = litellm_params.get("s3_bucket_name") or os.getenv("AWS_S3_BUCKET_NAME")
        if not bucket_name:
            raise ValueError(
                "S3 bucket_name is required. Set 's3_bucket_name' in litellm_params or AWS_S3_BUCKET_NAME env var"
            )
        bucket_name, object_prefix = split_configured_cloud_bucket_name(bucket_name)

        s3_region_name: Final = litellm_params.get("s3_region_name") or optional_params.get("s3_region_name")
        aws_region_name: Final = s3_region_name or self._get_aws_region_name(request_params, model)

        file_data: Final = data.get("file")
        purpose: Final = data.get("purpose")
        if file_data is None:
            raise ValueError("file is required")
        if purpose is None:
            raise ValueError("purpose is required")
        extracted_file_data: Final = extract_file_data(file_data)
        object_name = self.get_object_name(extracted_file_data, purpose)
        if object_prefix:
            object_name = f"{object_prefix}/{object_name}"
        encoded_object_name: Final = encode_s3_object_key_for_url(object_name)

        # S3 endpoint URL format
        s3_endpoint_url: Final = (
            request_params.get("s3_endpoint_url") or f"https://s3.{aws_region_name}.amazonaws.com"
        ).rstrip("/")

        return f"{s3_endpoint_url}/{bucket_name}/{encoded_object_name}"

    def get_supported_openai_params(self, model: str) -> list[OpenAICreateFileRequestOptionalParams]:
        return []

View on GitHub (pinned to 6c2dcb801b)

Solutions

1. Send the request as multipart/form-data with a part named exactly 'file'.
2. Verify with curl: curl -F file=@batch.jsonl -F purpose=batch .../v1/files.
3. Fix client SDK form construction to include the file part.

Example fix

# before (no file part)
requests.post(url, json={"purpose": "batch"})

# after
requests.post(url, files={"file": open("batch.jsonl", "rb")}, data={"purpose": "batch"})

assert data.get("file") is not None, "multipart field 'file' is required"

try:
    resp = litellm.create_file(file=f, purpose="batch")
except ValueError as e:
    if "file is required" in str(e):
        return HTTP 400  # client must send multipart
    raise

When it happens

Trigger: POSTing a files request without the multipart file part — malformed form data, wrong field name ('file' vs 'fileUpload'), or a JSON body where a file cannot be represented.

Common situations: Client sends JSON instead of multipart/form-data; field name mismatch between client SDK and litellm's expected 'file'; proxies stripping multipart parts; tests posting metadata only.

Related errors

• file content is required
• purpose is required
• File data is required
• file_id is required in file_content_request
• file_id must be a managed LiteLLM S3 file id

AI-assisted analysis of BerriAI/litellm@6c2dcb801b (2026-08-15). Data as JSON: /api/errors/7875f18464e7f838. Report an issue: GitHub.