Make sure hmac isn't given a unicode string

[kyrrigle]

So I ran into a problem with this today where the headers were unicode which isn't supported for python2 hmac. Converting to a bytearray seems like a reasonable guard against this and might help others.

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[rnicholus]

Were you able to verify this locally such that it fixes your issue and didn't cause any other obvious issues? I'm not using Python on any projects and am unable to verify at this time?

[kyrrigle]

Yes...

Starting the code thusly-

AWS_CLIENT_SECRET_KEY=foobar python app.py

and sending in a request-

curl --request POST \
  --url http://localhost:5000/s3/sign \
  --header 'content-type: application/json' \
  --data '{"headers":"😎"}'

The un-patched code throws a 500 error while the patch-1 code returns-

{ "signature": "lifmnNdZDK4yrGeX875UyCdFEkM=" }

As a sanity check if I instead send in an innocuous header text both versions come up with the same signature-

{ "headers": "some text to sign" }

{ "signature": "Tb2/i33y+AoKgKr+8BakjLWuMjE=" }

[rnicholus]

Cool. Thanks for finding & fixing this!

[kyrrigle]

No problem. Thanks for providing the examples!