Signature calculation has now moved out from being a package to
top-level as a layered mechanism.
In case of payload calculation with body, go-routines are initiated
to simultaneously write and calculate shasum. Errors are sent
over the writer so that the lower layer removes the temporary files
properly.
HMAC is a much simpler implementation, providing the same
benefits as RSA, avoids additional steps and keeps the code
simpler.
This patch also additionally
- Implements PutObjectURL API.
- GetObjectURL, PutObjectURL take TargetHost as another
argument for generating URL's for proper target destination.
- Adds experimental TLS support for JSON RPC calls.