Function sign 

pub fn sign(secret: &[u8], message: &[u8]) -> String

HMAC-SHA256 of message with secret, as lowercase hex: the signature to send in a header (X-Signature) of an outgoing call.

Examples

let signature = ocre::webhooks::sign(b"secret", b"{\"id\":1}");
assert_eq!(signature.len(), 64);
assert!(ocre::webhooks::verify(b"secret", b"{\"id\":1}", &signature).is_ok());