S3 PutObject with gzip stream not working with the integrity change - content length required for non-file data streams

[ohana54]

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

Hi,

I encountered the following bug after upgrading the sdk to the latest version (from a very old version).
When using S3 PutObject with a file read stream piped to a gzip stream, I get an error:

TypeError [ERR_HTTP_INVALID_HEADER_VALUE]: Invalid value "undefined" for header "x-amz-decoded-content-length"

Regression Issue

• Select this option if this issue appears to be a regression.

SDK version number

@aws-sdk/client-s3@3.911.0

Which JavaScript Runtime is this issue in?

Node.js

Details of the browser/Node.js/ReactNative version

Node.js v24.5.0

Reproduction Steps

import { PutObjectCommand, S3Client } from "@aws-sdk/client-s3";
import * as fs from "node:fs";
import * as path from "node:path";
import * as zlib from "node:zlib";

const s3 = new S3Client();
const body = fs.createReadStream('path-to-file')
  .pipe(zlib.createGzip());

s3.send(
  new PutObjectCommand({
    Bucket: 'bucket',
    Key: 'key',
    Body: body,
  })
);

Observed Behavior

An error was encountered in a non-retryable streaming request.
node:_http_outgoing:645
  validateHeaderValue(name, value);
  ^

TypeError [ERR_HTTP_INVALID_HEADER_VALUE]: Invalid value "undefined" for header "x-amz-decoded-content-length"
    at ClientRequest.setHeader (node:_http_outgoing:645:3)
    at new ClientRequest (node:_http_client:354:14)
    at request (node:http:102:10)
    at /Users/***/test-s3-client/node_modules/@smithy/node-http-handler/dist-cjs/index.js:324:25
    at new Promise (<anonymous>)
    at NodeHttpHandler.handle (/Users/***/test-s3-client/node_modules/@smithy/node-http-handler/dist-cjs/index.js:265:16)
    at async /Users/***/test-s3-client/node_modules/@aws-sdk/middleware-flexible-checksums/dist-cjs/index.js:372:20
    at async /Users/***/test-s3-client/node_modules/@aws-sdk/middleware-sdk-s3/dist-cjs/index.js:422:20
    at async /Users/***/test-s3-client/node_modules/@smithy/middleware-serde/dist-cjs/index.js:6:26 {
  code: 'ERR_HTTP_INVALID_HEADER_VALUE'
}

Expected Behavior

No error, request succeeds

Possible Solution

No response

Additional Information/Context

I traced it to the checksum middleware which is now active due to the default integrity change.
The checksum middleware is putting this header, which is undefined because the content-length middleware can't calculate the size of the gzip stream.

Is it correct to assume I need to disable checksum calculation as it's not possible for the sdk to do it without content length?

[kuhe]

Options I see:

1. (recommended) use the Upload class from @aws-sdk/lib-storage. This will buffer the stream into pieces to calculate their content lengths and upload them with checksums. It will either use PutObject for small data or MultipartUpload for larger data. Usage: https://www.npmjs.com/package/@aws-sdk/lib-storage
2. Provide the operation a value for ContentLength. This is the length of the gzip stream. I believe you wouldn't know this number unless you gzipped into the file system and then read the file length.
3. (not recommended) disable checksum calculation. This is not recommended since your data integrity will no longer be guaranteed. Please use option 1, and only do this as a last resort.