Intermittent 400 error on PUT http://api.aspose.cloud/v3.0/pdf/{filename}/fields

Aspose.PDF Cloud Product Family
1

Hi Team,

We’ve been facing this issue for a while now, and have investigated multiple issues on our side.
We use the REST API for the Aspose.PDF Cloud endpoints.

When calling this endpoint: PUT http://api.aspose.cloud/v3.0/pdf/{filename}/fields
We often receive a 400 Error - the logs cut off most of the message.

Retrying often succeeds (but not always) which leads me to think its an Aspose side issue (as nothing changes between the requests).

Can you please assist us looking into this issue?
Here are a couple of Request Id failures from today:
b5f75ca2-96a4-4572-83e0-b4375da20bb4
cae3968f-364f-474d-b61a-a8b8f2dde179
94dde890-35a5-4f8e-86ad-b426463305bc

Thankyou

2

Hi, @aspose.heffron.au
Can you please share your sample document and code to reproduce the issue? We will further proceed to assist you accordingly.

3

Hi @kirill.novinskiy
Thanks, sorry it took a while for me to come back to you!

Here is the template document:
01-10852-DEMO_666666-Trustee-Declaration.pdf (404.0 KB)

and here is the PUT we are making to the REST API:
https://api.aspose.cloud/v3.0/pdf/01-10852-DEMO_666666-Trustee-Declaration.pdf/fields
body:

"{"list":[{"name":"FundName","values":["Heffron Maestro Fund"]},{"name":"DirTeeFullName","values":["Joe Superannuation"]},{"name":"Day","values":[""]},{"name":"Month","values":[""]},{"name":"Year","values":[""]},{"name":"DayW","values":[""]},{"name":"MonthW","values":[""]},{"name":"YearW","values":[""]}]}"
4

@aspose.heffron.au Thank you for your reply, we will provide you with assistance as soon as possible.

5

@aspose.heffron.au, Please check this code

curl --location --request PUT 'https://api.aspose.cloud/v3.0/pdf/storage/file/TestFolder/01-10852-DEMO_666666-Trustee-Declaration.pdf' \
--header 'Authorization: Bearer YOUR_ACCESS_TOKEN' \
--form 'file=@"/PATH_TO_FILE/01-10852-DEMO_666666-Trustee-Declaration.pdf"'

curl --location --request PUT 'https://api.aspose.cloud/v3.0/pdf/01-10852-DEMO_666666-Trustee-Declaration.pdf/fields?folder=TestFolder' \
--header 'Authorization: Bearer YOUR_TOKEN_HERE' \
--header 'Content-Type: application/json' \
--data '{
                "list": 
                [
                    {
                        "name": "FundName",
                        "values": [
                            "Heffron Maestro Fund"
                        ]
                    },
                    {
                        "name": "DirTeeFullName",
                        "values": [
                            "Joe Superannuation"
                        ]
                    },
                    {
                        "name": "Day",
                        "values": [
                            ""
                        ]
                    },
                    {
                        "name": "Month",
                        "values": [
                            ""
                        ]
                    },
                    {
                        "name": "Year",
                        "values": [
                            ""
                        ]
                    },
                    {
                        "name": "DayW",
                        "values": [
                            ""
                        ]
                    },
                    {
                        "name": "MonthW",
                        "values": [
                            ""
                        ]
                    },
                    {
                        "name": "YearW",
                        "values": [
                            ""
                        ]
                    }
                ]
            }'
6

Hi @kirill.novinskiy - thanks for your response.
The payload looks identical - is the change just the ?folder param in the URL - we don’t want to put these into a folder, just into the root of the S3 bucket, which is why it was omitted.
It also doesn’t explain why some of the calls work and others error, even though the file and payload is identical.
Thanks

7

@aspose.heffron.au , Thanks for the clarification. Isn’t this a constant error? How often does it occur? Are you using standard storage or your own S3 bucket?

8

No its inconsistent - exact same request could succeed or fail.
The message we get back is:
“status”: 400,
“resp_body”: “{"RequestId":"be29630ad9ce81d810c3a5ea01ba029d","Error":{"Code":"error","Message":"AmazonS3 Storage exception: One or more errors occurred. (Unable to read data from the transport connection: Connection reset by peer.)","Description":"Operation Failed. Unable to read data from the transport connection: Connection reset by peer.","DateTime":"2026-05-11T01:41:44.6642Z","InnerError":null}}”
We’re using our own S3 storage - is there anything we should confirm on this.

9

Hi, @aspose.heffron.au Im report issue and logged the following ticket in our issue tracking system for further investigation and rectification. We will notify you as soon as these issues are resolved.

PDFCLOUD-5541 S3 Amazon storage connection error

10

Hi @kirill.novinskiy
Just wanted to share an update - when we hit this aspose error, we can see the following logged in our CloudTrail logs = please note the errorCode and errorMessage fields which indicate the call to s3 was invalid or incomplete:
{
“eventVersion”: “1.11”,
“userIdentity”: {
“type”: “IAMUser”,
“principalId”: “REDACTED”,
“arn”: “arn:aws:iam::REDACTED:user/REDACTED”,
“accountId”: “REDACTED”,
“accessKeyId”: “REDACTED”,
“userName”: “REDACTED”
},
“eventTime”: “2026-05-26T01:49:34Z”,
“eventSource”: “s3.amazonaws.com”,
“eventName”: “PutObject”,
“awsRegion”: “ap-southeast-2”,
“sourceIPAddress”: “74.113.210.254”,
“userAgent”: “[aws-sdk-dotnet-coreclr/4.0.6.7 ua/2.1 os/linux#5.15.0.140 md/ARCH#X64 lang/.NET_Core#8.0.26 md/aws-sdk-dotnet-core#4.0.0.23 api/S3#4.0.6.7 md/ClientAsync cfg/init-coll#0 m/b,P,e,E,U,Z]”,
“errorCode”: “IncompleteBody”,
“errorMessage”: “The request body terminated unexpectedly”,
“requestParameters”: {
“bucketName”: “REDACTED”,
“Host”: “REDACTED.s3.ap-southeast-2.amazonaws.com”,
“key”: “REDACTED.pdf”
},
“responseElements”: null,
“additionalEventData”: {
“SignatureVersion”: “SigV4”,
“CipherSuite”: “TLS_AES_128_GCM_SHA256”,
“bytesTransferredIn”: 90202,
“AuthenticationMethod”: “AuthHeader”,
“x-amz-id-2”: “REDACTED”,
“bytesTransferredOut”: 292
},
“requestID”: “XGN07TA0KHGVRMB7”,
“eventID”: “f7454276-142b-49f3-8055-c350193307ce”,
“readOnly”: false,
“resources”: [
{
“accountId”: “REDACTED”,
“type”: “AWS::S3::Bucket”,
“ARN”: “arn:aws:s3:::REDACTED”
},
{
“type”: “AWS::S3::Object”,
“ARN”: “arn:aws:s3:::REDACTED/REDACTED.pdf”
}
],
“eventType”: “AwsApiCall”,
“managementEvent”: false,
“recipientAccountId”: “REDACTED”,
“eventCategory”: “Data”,
“tlsDetails”: {
“tlsVersion”: “TLSv1.3”,
“cipherSuite”: “TLS_AES_128_GCM_SHA256”,
“clientProvidedHostHeader”: “REDACTED.s3.ap-southeast-2.amazonaws.com”
}
}

11

@aspose.heffron.au , thank you for the clarification, we are working to resolve the issue.