Fix base64 error when input is multiple of 4 bytes #4
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The base64Decode function was incorrectly re-adding padding when the input is a multiple of 4 bytes. These input lengths should have no padding, but it was adding 1, which led to an error: > illegal base64 data at input byte 4 The base64 package has options to omit padding using `WithPadding(base64.NoPadding)`[1], and also defines Raw versions of the pre-defined encoders[2]. This therefore updates the functions to use these encoders instead, which means they're now just simple wrappers. [1]https://pkg.go.dev/encoding/base64#Encoding.WithPadding [2]https://pkg.go.dev/encoding/base64#pkg-variables
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The base64Decode was incorrectly re-adding padding when the input is a multiple of 4 bytes. These input lengths should have no padding, but it was adding 1, which led to an error: illegal base64 data at input byte 4.
The base64 package has options to omit padding using
WithPadding(base64.NoPadding)[1], and also defines Raw versions of the pre-defined encoders[2]. This therefore updates the functions to use these encoders instead, which means they're now just simple wrappers.I suspect this hasn't been an issue before now, because neither the timestamp or signature encode to a base64 value which is a multiple of 4 bytes. I ran into this while working on extending this to implement URLSafeTimedSerializer that's present in the Python version, which also handles base64 encoding the value, which can be an arbirtary length.
[1]https://pkg.go.dev/encoding/base64#Encoding.WithPadding
[2]https://pkg.go.dev/encoding/base64#pkg-variables