Setting metadata on S3 multipart upload

Question

I'd like to upload a file to S3 in parts, and set some metadata on the file. I'm using boto to interact with S3. I'm able to set metadata with single-operation uploads like so:

Is there a way to set metadata with a multipart upload? I've tried this method of copying the key to change the metadata, but it fails with the error: InvalidRequest: The specified copy source is larger than the maximum allowable size for a copy source: <size>

I've also tried doing the following:

key = bucket.create_key(key_name)
key.set_metadata('some-key', 'value')
<multipart upload>

...but the multipart upload overwrites the metadata.

I'm using code similar to this to do the multipart upload.

Answer 1

Sorry, I just found the answer:

Per the docs:

If you want to provide any metadata describing the object being uploaded, you must provide it in the request to initiate multipart upload.

So in boto, the metadata can be set in the initiate_multipart_upload call. Docs here.