This PR allows 'minio update' to not only shows update banner
but also allows for in-place upgrades.
Updates are done safely by validating the downloaded
sha256 of the binary.
Fixes#4781
This check incorrectly rejects most valid filenames. The only filenames Sia
forbids are leading forward slashes and path traversal characters, but it's
better to simply allow Sia to reject invalid names on its own rather than try
to anticipate errors from Sia:
https://github.com/NebulousLabs/Sia/blob/master/doc/api/Renter.md#path-parameters-4
Current implementation we faked the makeBucket operations
to allow for s3 clients to behave properly. But instead
we can create a placeholder zero byte file instead, which
is a hexadecimal representation of the bucket name itself.
The Sia gateway had a bug with uploading that prevented the user's uploads
from reaching the Sia backend. The PutObject function called fsRemoveFile at
the end of the function, which didn't give the Sia backend enough time to
upload the file to the Sia network.
This adds a goroutine that watches the file upload progress and doesn't delete
the file until the upload reaches 100% complete.
Note that this solution has the limitation where if the minio process dies in
the middle of upload, it will leave orphaned files in the SIA_TEMP directory
that the user will need to remove manually.
Harshavardhana