HMAC is a mechanism for message authentication using cryptographic hash functions.
This HMAC function uses the iterative cryptographic hash function SHA-1 with a secret shared key.
Use this function to generate a digital signature that is compliant with HMAC.
Parameter: data (type=string)
The information or message to be validated.
Parameter: key (type=string)
The key used to validate the data.
Parameter: encoding (type=string)
Returns: HMAC signature (type string)
The generated HMAC signature in UTF-8 encoding.