HMAC-SHA256 signature crypto

nodejs-request.js

let now            = new Date ();
		let ISODate        = new Date ( now.toISOString () );
		let TimeStamp      = ISODate.getTime ();
		let api_access_key = "key1";
		let api_secret_key = "key2";
		let url            = "https://test-emoney-services.w-ha.com/api/";
		let body           = {
			"subscriber" : {
				"lastname" : "Martin",
				"firstname" : "Philippe",
				"birthdate" : "1986-03-01",
				"nationality" : "FRA"
			},
			"address" : {
				"label1" : "12 rue de Stalingrad",
				"zip_code" : "92800",
				"city" : "Puteaux",
				"country" : "FRA"
			},
			"email" : "m.philippe@wha.fr",
			"tag" : "account_type1"
		};
		let hmac = crypto.createHmac ( 'sha256', api_secret_key );
		hmac.update ( api_access_key + ':' + TimeStamp + ':1:' + JSON.stringify ( body ) );
		let signature = hmac.digest ( 'hex' );
		
		let options = {
			method : 'post',
			url : url + 'accounts/standard',
			json : true,
			headers : {
				'Authorization' : 'AUTH ' + api_access_key + ':' + TimeStamp + ':1:' + signature,
				'Content-Type' : 'application/json'
			},
			body : body
		};
		request ( options, function callback ( error, response, body ) {
			if ( error ) {
				res.send ( error )
			} else {
				res.send ( body );
			}
		} );