When using the File Download card in Workflows to download a file, the download may fail with the following error.
S3 Error: blobservice::Error
The relevant error within the message portion of the complete error message is:
Your metadata headers exceed the maximum allowed metadata size
{
"_error": true,
"retry_count": 0,
"flo": 953608,
"method": "AxLR241Ny",
"execution": "4057743d-0d79-415d-8d59-d2567e8903ba",
"module": "filefunctions.largeDownload",
"kind": "Unknown Error",
"message": "S3 Error: blobservice::Error { kind: Unknown, desc: \"ServiceError(ServiceError { source: Unhandled(Unhandled { source: ErrorMetadata { code: Some(\\\"MetadataTooLarge\\\"), message: Some(\\\"Your metadata headers exceed the maximum allowed metadata size\\\"), extras: Some({\\\"aws_request_id\\\": \\\"F0XJYBAEVC4WQJ4D\\\", \\\"s3_extended_request_id\\\": \\\"y/0axDsrglzuycyO5hHVT/+lrSJaPpUjecAv7zn2Gq7uD+2fvf+6qOIHKbLCcE3BqpCWsSu1yHw=\\\"}) }, meta: ErrorMetadata { code: Some(\\\"MetadataTooLarge\\\"), message: Some(\\\"Your metadata headers exceed the maximum allowed metadata size\\\"), extras: Some({\\\"aws_request_id\\\": \\\"F0XJYBAEVC4WQJ4D\\\", \\\"s3_extended_request_id\\\": \\\"y/0axDsrglzuycyO5hHVT/+lrSJaPpUjecAv7zn2Gq7uD+2fvf+6qOIHKbLCcE3BqpCWsSu1yHw=\\\"}) } }), raw: Response { status: StatusCode(400), headers: Headers { headers: {\\\"x-amz-request-id\\\": HeaderValue { _private: H0(\\\"F0XJYBAEVC4WQJ4D\\\") }, \\\"x-amz-id-2\\\": HeaderValue { _private: H0(\\\"y/0axDsrglzuycyO5hHVT/+lrSJaPpUjecAv7zn2Gq7uD+2fvf+6qOIHKbLCcE3BqpCWsSu1yHw=\\\") }, \\\"content-type\\\": HeaderValue { _private: H0(\\\"application/xml\\\") }, \\\"transfer-encoding\\\": HeaderValue { _private: H0(\\\"chunked\\\") }, \\\"date\\\": HeaderValue { _private: H0(\\\"Thu, 15 May 2025 17:58:22 GMT\\\") }, \\\"connection\\\": HeaderValue { _private: H0(\\\"close\\\") }, \\\"server\\\": HeaderValue { _private: H0(\\\"AmazonS3\\\") }} }, body: SdkBody { inner: Once(Some(b\\\"<?xml version=\\\\\\\"1.0\\\\\\\" encoding=\\\\\\\"UTF-8\\\\\\\"?>\\\\n<Error><Code>MetadataTooLarge</Code><Message>Your metadata headers exceed the maximum allowed metadata size</Message><Size>2086</Size><MaxSizeAllowed>2048</MaxSizeAllowed><RequestId>F0XJYBAEVC4WQJ4D</RequestId><HostId>y/0axDsrglzuycyO5hHVT/+lrSJaPpUjecAv7zn2Gq7uD+2fvf+6qOIHKbLCcE3BqpCWsSu1yHw=</HostId></Error>\\\")), retryable: true }, extensions: Extensions { extensions_02x: Extensions, extensions_1x: Extensions } } })\", source: None }",
"code": 500,
"description": "Unknown Error",
"steps": 21,
"desc": "S3 Error",
"_fatal": null,
"source": {
"flo": "filefunctions:1.0.46:largeDownload",
"method": "OeNm96k5Xtv0T",
"execution": "ddd14cb9-1578-42d2-906e-bc5a826db602",
"module": "file.pullAsync"
}
}
- Workflows
- File Download card
When downloading a file using the File Download card, Workflows adds metadata headers that are needed to store the file in the workflows platform file system. This may result in the size of the metadata headers exceeding the maximum of 2048, resulting in the "Your metadata headers exceed the maximum allowed metadata size" error.
This can occur when the download URL has a large query string consisting of several query parameters and/or large query parameter values. One scenario where this error can occur is when using the File Download card to down a file from AWS S3 using a presigned URL generated in AWS.
Pass the query parameters in the Query input of the File Download card rather than on the URL query string. As an example, when using an AWS presigned URL, the link includes several query parameters, including a lengthy string in the X-Amz-Security-Token parameter that may cause the download to fail:
