GetObjectCommand circular reference

[vander99]

Checkboxes for prior research

• I've gone through Developer Guide and API reference
• I've checked AWS Forums and StackOverflow.
• I've searched for previous similar issues and didn't find any solution.

Describe the bug

Hello, I am trying to download a file from nestjs, send it to angular server using a REST POST endpoint in order to trigger the download of this file.

But I get this error:
ERROR [ExceptionsHandler] Converting circular structure to JSON
--> starting at object with constructor 'TLSSocket'
| property 'parser' -> object with constructor 'HTTPParser'
--- property 'socket' closes the circle
Do you have a solution to this probleme ?

Her is my controller:
@post('download')
async downloadFile(@Body() body:bodyObject) {
return await this.s3Client.send(
new GetObjectCommand({
Bucket: 'bucket-name',
Key: file-name,
}));
}

My nodejs version: v20.10.0
nestjs version: @nestjs/core@8.4.7
aws-sdk/client-s3 version: 3.554.0

SDK version number

@aws-sdk/client-s3@3.556.0

Which JavaScript Runtime is this issue in?

Node.js

Details of the browser/Node.js/ReactNative version

v20.10.0

Reproduction Steps

Download a file from s3 using GetObjectCommand then send it by rest endpoint to a frontend server

@post('download')
async downloadFile(@Body() body:bodyObject) {
return await this.s3Client.send(
new GetObjectCommand({
Bucket: 'bucket-name',
Key: file-name,
}));
}

Observed Behavior

Error:

ERROR [ExceptionsHandler] Converting circular structure to JSON
--> starting at object with constructor 'TLSSocket'
| property 'parser' -> object with constructor 'HTTPParser'
--- property 'socket' closes the circle

Expected Behavior

The file to be send, so we can trigger then download in the frontend

Possible Solution

No response

Additional Information/Context

No response

[aBurmeseDev]

Hi @vander99 - thanks for reaching out.

i think the error you're seeing is more of NestJS related rather than SDK. From my quick research, this error is occurs when you try to convert an object into JSON but the object contains a circular reference. Here are my search results.

If you need further assistance, please share a larger code snippet of your file to give me more insight.

Hope it helps,
John

[vander99]

Hello,

The error is related to the fact that the api returns a circular reference, so their is no way we could send the response anywhere by using http request.

The snippet is easy I shared it above, I want only to get the file from s3 and send it via http request so I can download it in my front end.

The question is, how can we get a file from s3 using nestjs and send it to a frontend by using http request knowing that the api returns a circular reference. If no is their a fix comming so the api won't return a circular reference. If no why does the api return a circular reference ?