Hex, base64 encoding

Sometimes you need to encode bytes into a text.

Most popular encodings are hex, where each byte is represented by 2 characters and base64 where each 3 bytes are encoded as 4 characters.

Hex encode and decode

We can encode a []byte into a string and decode from string into []byte.

We can encode to string using fmt.Sprintf and %x directive. Similarly, we can decode using fmt.Sscanf and %x.

Directive %x supports integers in addtion to []byte.

For encoding and decoding larger values in streaming mode, we can encode to a io.Writer and decode from io.Reader.

We can encode a []byte into a string and decode from string into []byte.

Original base64 encoding unfortunately might produce characters that are not valid in urls.

Given that urls are important those days we have a variant of base64 encoding that doesn’t have that flaw: