Function http_sign::sign

pub fn sign<'sig_elems, SigAlg, Req, IntoSigElements>(
    scheme: SignatureScheme, 
    sig_alg: &SigAlg, 
    request: &mut Req, 
    expiration: Duration, 
    signature_elements: &[SignatureElement<'_>]
) -> Result<(), SignError> where
    SigAlg: SignatureAlgorithm,
    Req: Request,