Following the basic example in the docs (S3Client.putObject(bucketName, objectKey, data))
Produces the following error:
S3ServiceError: There were headers present in the request which were not signed
I’m not sure what I’m doing wrong here. I just replaced the bucket name with one that I own and added my keys in the ENV.
Welcome to the community forums 
Thanks for reporting this issue. So far, from my investigations, it seems something introduced in version 0.7.0. While we keep digging, the example should work fine with version 0.6.0. I changed the import and the example worked for me:
import { AWSConfig, S3Client } from 'https://jslib.k6.io/aws/0.6.0/s3.js';
If you are looking for more examples you can also visit the repository: https://github.com/grafana/k6-jslib-aws/blob/main/examples/s3.js
I’ll get back here once we figure out what changed. Again, many thanks for spotting this.
Cheers!
Thanks! It seems to have worked. Is there a way to customize the headers (such as Content-Type or Content-Disposition)?
Thanks for your patience. I opened the issue Error some headers are not signed with version 0.7.0 · Issue #28 · grafana/k6-jslib-aws · GitHub and proposed a PR to fix this. I’ll discuss this with the maintainer, as this is simply my proposal. You can follow the issue to see how it’s finally resolved.
Looking at the code I think it’s not possible to add headers such as Content-Type or Content-Disposition. We are always passing empty headers and the code creates the authentication/signing headers. It looks like a good feature to add, so I went ahead and opened: Support for headers like Content-Disposition or Content-Type with putObject · Issue #30 · grafana/k6-jslib-aws · GitHub.
Many thanks for your contributions 
Cheers!
We published the fix in version 0.7.1. The following import should work now:
import { AWSConfig, S3Client } from 'https://jslib.k6.io/aws/0.7.1/s3.js';
Let us know if you are still hitting issues. And many thanks for reporting this.
Cheers!