.. _oldsamples:

Old server-side code samples
============================

Server

.. code-block:: java

	@RestController
	public class ProcController implements ExternalAuthenticateHandler, MutualAuthenticateHandler {

		/* This is the private key for SCWS environment creation
		* (should correspond to the public key for which the webappcert has been generated)
		* Note: the webappcert is in the javascript code */
		private static final String privateKeyPEM = 
				"-----BEGIN RSA PRIVATE KEY-----\r\n" + 
				"MIIBOgIBAAJBAMPMNNpbZZddeT/GTjU0PWuuN9VEGpxXJTAkmZY02o8238fQ2ynt\r\n" + 
				"N40FVl08YksWBO/74XEjU30mAjuaz/FB2kkCAwEAAQJBALoMlsROSLCWD5q8EqCX\r\n" + 
				"rS1e9IrgFfEtFZczkAWc33lo3FnFeFTXSMVCloNCBWU35od4zTOhdRPAWpQ1Mzxi\r\n" + 
				"aCkCIQD9qjKjNvbDXjUcCNqdiJxPDlPGpa78yzyCCUA/+TNwVwIhAMWZoqZO3eWq\r\n" + 
				"SCBTLelVQsg6CwJh9W7vlezvWxUni+ZfAiAopBAg3jmC66EOsMx12OFSOTVq6jiy\r\n" + 
				"/8zd+KV2mnKHWQIgVpZiLZo1piQeAvwwDCUuZGr61Ap08C3QdsjUEssHhOUCIBee\r\n" + 
				"72JZuJeABcv7lHhAWzsiCddVAkdnZKUo6ubaxw3u\r\n" + 
				"-----END RSA PRIVATE KEY-----";
		
		/**
		* Entry point for generating the signature, for the initial environment creation.
		* (called by the client between SCWS.findService and SCWS.createEnvironment).
		* @param rnd the challenge to sign (coming from the client-side SCWS).
		* @return the cryptogram that will authorize environment creation.
		*/ 
		@GetMapping("/sign_env_challenge")
		public String signEnvChallenge(String rnd) {
			try {
				PrivateKey privateKey;
				try (PEMParser pemParser = new PEMParser(new StringReader(privateKeyPEM))) {
					JcaPEMKeyConverter converter = new JcaPEMKeyConverter().setProvider("BC");
					Object object = pemParser.readObject();
					KeyPair kp = converter.getKeyPair((PEMKeyPair)object);
					privateKey = kp.getPrivate();
				}
				Signature signer = Signature.getInstance("NONEwithRSA","BC");
				signer.initSign(privateKey);
				signer.update(Hex.decode(rnd));
				byte[] signature = signer.sign();
				return Hex.toHexString(signature);
			} catch (Exception e) {
				e.printStackTrace();
				throw new RuntimeException(e.getMessage(), e);
			}
		}
		
		/**
		* Create a {@link SCSSSession} object.
		* @return the handle of created {@link SCSSSession} object.
		* @throws SCMException
		* @throws IOException
		*/
		@GetMapping("/init_session")
		public String startTest() throws SCMException, IOException {
			final SCSSSession s = new SCSSSession();
			return s.getHandle();
		}
		
		/**
		* Process session and allow communication between ServerSide SmartCard and ClientSide SmartCard middlewares.
		* @param id the handle of the {@link SCSSSession} object to communicate with.
		* @param body the body of HTTP request
		* @return the result of processed session.
		* @throws SCMException
		* @throws IOException
		*/
		@PostMapping("/process_session/{id}")
		public String processSession(@PathVariable String id, @RequestBody String body) throws SCMException, IOException {
			return SCSSSession.process(id, body);
		}
		
		/**
		* Execute session. Once {@link SCSSSession} object is created and session is managed with {@link SCSSSession#process}, call this to use methods and attributes from 
		* {@link Token} object.
		* @param id the handle of {@link SCSSSession} object.
		* @return some result
		* @throws SCMException
		* @throws IOException
		*/
		@GetMapping("/exec_session/{id}")
		public String execSession(@PathVariable String id) throws SCMException, IOException {
			SCSSSession s = SCSSSession.getSession(id);
			
			try {
				s.init();
				
				/* -------------------------------------------------------------------- */
				// here lies the server-side application logic.
				// Operations are made by calling Token methods on the `s` object.
				/* -------------------------------------------------------------------- */
				
			}
			catch (Exception e){
				return "Operation failed";
			}
			finally {
				s.close();			
			}
			return "Operation OK";
		}
		
	}

Client

.. code-block:: javascript

	window.webappcert = "4SyF8E6?J4{SVYI)psu*Xb0t#E=1oJdCH}B[Y8){oDbd%GP-L&ZI*KtJl@P?<:t$Tvv[NPS9>6Mqkpnmg^O1Zkn[Zo#czsNjEe:ASWVef!l-I$=e02=*YAmCkmvm1iifG])b[EFTe2>-:Hmk.KPTX9S0CQPVV41h3>S0>QyDEq/Bb?u#Zc^i7v]JDE@jgy@*bbc=59z!woxg6nRpqTxix&o8>5J8D6lzoLkuw=Q8MreUlGfHfBt(&q8!8Eh>BBL.6A)S.&IBkyKcR%$V@Zb$.!0aJjM1<iEMzoN)2!j^GtkU:d>A/Rx=u*@Q7W6$kk[zM";

	window.connections = [];
	window.connecting = false;

	/* boilerplate function for performing a ajax request */
	function req(method, url, contents) {
		return new Promise(function(resolve, reject) {
			var req = new XMLHttpRequest();
			req.onreadystatechange = function () {
				if (this.readyState === 4) {
					if (this.status === 200)
						resolve(req.responseText);
					else
						reject(new Error("App server request failed"));
				}
			};
			req.open(method, url, true);
			req.send(contents);
		});
	}

	function reqGet(url) {
		return req("GET", url);
	}

	function reqPost(url, contents) {
		return req("POST", url, contents);
	}

	/* connects to the SCWS, then tries to find smart cards in readers and connect to them */
	function init() {
		/* connecting to SCWS */
		console.log("Connecting to SCWS...");
		SCWS.findService(window.webappcert).then(function(challenge) {
			console.log("Connection to SCWS succeeded");
			return reqGet("sign_env_challenge?rnd=" + challenge)
			.then(function(signature) {
				return SCWS.createEnvironment(signature);
			});
		}).then(function() {
			console.log("SCWS environment created successfully");
			/* check all readers already connected */
			var readers = SCWS.readers;
			if (readers.length == 0) {
				console.log("No readers found");
			}
			else {
				for (var i = 0; i < readers.length; i++)
					checkReader(readers[i]);
			}
			document.getElementById("initbtn").style.display = "none";
			updateStatus();
			/* register event callbacks for checking readers changes */
			SCWS.onreaderadded = function(reader) {
				console.log("Reader inserted: '" + reader.name + "'");
				checkReader(reader);
			}
			SCWS.onreaderremoved = function(reader) {
				console.log("Reader removed: '" + reader.name + "'");
				checkReader(reader);
			}
			SCWS.onreaderstatechanged = function(reader) {
				console.log("Reader state changed: '" + reader.name + "'");
				checkReader(reader);
			}
		}).catch(function(err) {
			console.log("ERROR: " + err.message);
		});
	}

	function updateStatus()
	{
		// update GUI elements to show connection state
	}

	/**
	* Called when a reader needs to be scanned for objects.
	*/
	function checkReader(reader) {
		/* trying to find reader from existing connections */
		for (var connidx = 0; connidx < window.connections.length; connidx++) {
			if (window.connections[connidx].reader == reader)
				break;
		}
		if (connidx == window.connections.length) {
			if (reader.status == "ok" && reader.cardPresent) {
				/* reader not found in existing connections, and reader contains card: connecting */
				console.log("Connecting to reader '" + reader.name + "'...");
				var connection = { reader: reader };
				window.connections.push(connection);
				window.connecting = true;
				updateStatus();
				reader.connect().then(function(token) {
					connection.token = token;
					connection.items = [];
					console.log("Getting objects from reader '" + reader.name + "'...");
					return token.getObjects();
				}).then(function(items) {
					connection.items = items;
					window.connecting = false;
					updateStatus();
				}).catch(function(err) {
					console.log("ERROR: " + err.message);
					window.connecting = false;
					updateStatus();
				});
			}
		}
		else {
			var conn = connections[connidx];
			if (reader.status != "ok" || !reader.cardPresent) {
				/* reader found in existing connections, but contains no card: removing */
				if (conn.token) {
					console.log("Disconnecting from reader '" + reader.name + "'.");
					conn.token.disconnect();
				}
				window.connections.splice(connidx, 1);
				updateStatus();
			}
		}
	}

	function showError(err) {
		document.getElementById("errmsg").textContent = err.message || err;
	}

	/* Function that actually opens the server session */
	function test() {
		/* first, create the SCSSSession instance on the server */
		reqGet("init_session").then(function(sessHandle) {
			/* process the session (session handle is used in the URL) */
			window.connections[0].token.processServerSession("process_session/" + sessHandle).then(function() {
				console.log("OK");
				/* at that point, the session is fully completed */
			}, function() {
				console.log("error");
			});
			/* concurrently with the processServerSession call, the REST entry point that actually performs the operation is called, also giving the session handle */ 
			reqGet("exec_session/" + sessHandle).then(function(result) {
				console.log(result);
				/* although the REST operation is completed, the session may not be yet finished at that point */
			});
		});
	}