added salto lock server and implemented workflow for Salto

lockserver/lockservercommon.go

@@ -15,6 +15,7 @@ import (
 const (
 	AssaAbloy = "assaabloy"
 	Omnitec   = "omnitec"
+	Salto     = "salto"
 )
 
 type (
@@ -32,6 +33,11 @@ type (
 		encoderAddr string // Encoder unit address
 		command []byte // Command to be sent to the lock server
 	}
+
+	SaltoLockServer struct {
+		encoderAddr string 
+		command []byte 
+	}
 )
 
 func NewLockServer(lockType, encoderAddr string, fatalError func(error)) LockServer {
@@ -40,6 +46,8 @@ func NewLockServer(lockType, encoderAddr string, fatalError func(error)) LockSer
 		return &AssaLockServer{encoderAddr: encoderAddr}
 	case Omnitec:
 		return &OmniLockServer{encoderAddr: encoderAddr}
+	case Salto:
+		return &SaltoLockServer{encoderAddr: encoderAddr}
 	default:
 		fatalError(fmt.Errorf("unsupported LockType: %s; must be 'assaabloy' or 'omnitec'", lockType))
 		return nil // This line will never be reached, but is needed to satisfy the compiler

lockserver/saltolockserver.go

@@ -0,0 +1,103 @@
+package lockserver
+
+import (
+	"fmt"
+	"net"
+	"time"
+
+	// "strings"
+
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	STX = 0x02 // Start of Text
+	ETX = 0x03 // End of Text
+	ENQ = 0x05 // Enquiry from host
+	ACK = 0x06 // Positive response
+	NAK = 0x15 // Negative response
+)
+
+func calculateLRC(data []byte) byte {
+	lrc := byte(0x00)
+	for _, b := range data {
+		lrc ^= b
+	}
+	return lrc
+}
+
+// simple join that avoids importing strings just for this.
+func stringJoin(parts []string, sep string) string {
+	if len(parts) == 0 {
+		return ""
+	}
+	out := parts[0]
+	for _, p := range parts[1:] {
+		out += sep + p
+	}
+	return out
+}
+
+// BuildCommand builds a Salto card‑issuance command in the form:
+//	STX|CN|<encoder addres>|E|<room>| | | | | |<start>|<expiry>|ETX|<LRC>
+// where <start> and <expiry> are hhmmDDMMYY, and LRC is the XOR of all bytes
+func (lock *SaltoLockServer) BuildCommand(lockId string, checkIn, checkOut time.Time) error {
+	// format helper: hhmmDDMMYY
+	fmtStamp := func(t time.Time) string {
+		return fmt.Sprintf("%02d%02d%02d%02d%02d",
+			t.Hour(), t.Minute(), t.Day(), int(t.Month()), t.Year()%100)
+	}
+
+	start := fmtStamp(checkIn)
+	expiry := fmtStamp(checkOut)
+
+	// the 12 fields between STX and ETX
+	fields := []string{
+		"CN", lock.encoderAddr, "E", lockId, "", "", "", "", "", "", start, expiry,
+	}
+
+	body := "|" + stringJoin(fields, "|") + "|" // leading/trailing pipes, so the ETX ends the last field
+
+	// wrap with STX/ETX
+	msg := append([]byte{STX}, []byte(body)...)
+	msg = append(msg, ETX)
+
+	// compute LRC over everything *after* STX up to and including ETX
+	lrc := calculateLRC(msg[1:]) // skip STX
+	msg = append(msg, lrc)
+
+	lock.command = msg
+	return nil
+}
+
+// Checks heart beat of the Assa Abloy lock server and perform key encoding
+func (lock *SaltoLockServer) LockSequence(conn net.Conn) error {
+	const funcName = "SaltoLockServer.LockSequence"
+
+	// Step 1: ENQ to check availability
+	respStr, err := sendAndReceive(conn, []byte{ENQ})
+	if err != nil {
+		return fmt.Errorf("[%s] failed sending ENQ: %w", funcName, err)
+	}
+	resp := []byte(respStr)
+
+	if len(resp) != 1 || resp[0] != ACK {
+		return fmt.Errorf("[%s] expected ACK (0x06) after ENQ, got: %q (hex: % X)", funcName, respStr, resp)
+	}
+
+	// Step 2: Send actual command
+	respStr, err = sendAndReceive(conn, lock.command)
+	if err != nil {
+		return fmt.Errorf("[%s] failed sending command: %w", funcName, err)
+	}
+	resp = []byte(respStr)
+
+	if len(resp) == 1 && resp[0] == NAK {
+		return fmt.Errorf("[%s] command rejected by lock server (NAK)", funcName)
+	}
+
+	log.Infof("Encoding response: %q", respStr)
+	return nil
+}
+
+

main.go

@@ -30,7 +30,7 @@ import (
 )
 
 const (
-	buildVersion   = "1.0.0"
+	buildVersion   = "1.0.1"
 	serviceName    = "hardlink"
 	customLayout   = "2006-01-02 15:04:05 -0700"
 	transactionUrl = "http://127.0.0.1:18181/start-transaction/"
@@ -46,10 +46,7 @@ type configRec struct {
 	DispenserAdrr  string `yaml:"dispensAddr"`
 	PrinterName    string `yaml:"printerName"`
 	LogDir         string `yaml:"logdir"`
-	dbport         int    `yaml:"dbport"`     // Port for the database connection
-	dbname         string `yaml:"dbname"`     // Database name for the connection
-	dbuser         string `yaml:"dbuser"`     // User for the database connection
-	dbpassword     string `yaml:"dbpassword"` // Password for the database connection
+	isPayment      bool   `yaml:"isPayment"`
 }
 
 // DoorCardRequest is the JSON payload for /issue-door-card.
@@ -124,60 +121,62 @@ func main() {
 	// }
 	// defer db.Close()
 
-	startClient := func() (*exec.Cmd, error) {
-		cmd := exec.Command("./ChipDNAClient/ChipDnaClient.exe")
-		err := cmd.Start()
-		if err != nil {
-			return nil, fmt.Errorf("Failed to start ChipDnaClient: %v", err)
-		}
-		log.Infof("ChipDnaClient started with PID %d", cmd.Process.Pid)
-		return cmd, nil
-	}
-
-	cmd, err := startClient()
-	if err != nil {
-		fatalError(err)
-	}
-
-	// Restart loop
-	go func() {
-		for {
-			err := cmd.Wait()
+	if config.isPayment {
+		startClient := func() (*exec.Cmd, error) {
+			cmd := exec.Command("./ChipDNAClient/ChipDnaClient.exe")
+			err := cmd.Start()
 			if err != nil {
-				log.Errorf("ChipDnaClient exited unexpectedly: %v", err)
-				time.Sleep(2 * time.Second)
-				cmd, err = startClient()
-				if err != nil {
-					log.Errorf("Restart failed: %v", err)
-					return
-				}
-				log.Info("ChipDnaClient restarted successfully")
+				return nil, fmt.Errorf("failed to start ChipDnaClient: %v", err)
 			}
+			log.Infof("ChipDnaClient started with PID %d", cmd.Process.Pid)
+			return cmd, nil
 		}
-	}()
 
-	// Handle shutdown signals
-	sigs := make(chan os.Signal, 1)
-	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
-	go func() {
-		<-sigs
-		log.Info("Shutting down...")
-		if cmd.Process != nil {
-			log.Info("Sending SIGTERM to ChipDnaClient...")
-			_ = cmd.Process.Signal(syscall.SIGTERM)
-			// wait up to 5s for graceful shutdown
-			done := make(chan error, 1)
-			go func() { done <- cmd.Wait() }()
-			select {
-			case <-time.After(5 * time.Second):
-				log.Warn("ChipDnaClient did not exit in time, killing...")
-				_ = cmd.Process.Kill()
-			case err := <-done:
-				log.Infof("ChipDnaClient exited cleanly: %v", err)
-			}
+		cmd, err := startClient()
+		if err != nil {
+			fatalError(err)
 		}
-		os.Exit(0)
-	}()
+
+		// Restart loop
+		go func() {
+			for {
+				err := cmd.Wait()
+				if err != nil {
+					log.Errorf("ChipDnaClient exited unexpectedly: %v", err)
+					time.Sleep(2 * time.Second)
+					cmd, err = startClient()
+					if err != nil {
+						log.Errorf("Restart failed: %v", err)
+						return
+					}
+					log.Info("ChipDnaClient restarted successfully")
+				}
+			}
+		}()
+
+		// Handle shutdown signals
+		sigs := make(chan os.Signal, 1)
+		signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
+		go func() {
+			<-sigs
+			log.Info("Shutting down...")
+			if cmd.Process != nil {
+				log.Info("Sending SIGTERM to ChipDnaClient...")
+				_ = cmd.Process.Signal(syscall.SIGTERM)
+				// wait up to 5s for graceful shutdown
+				done := make(chan error, 1)
+				go func() { done <- cmd.Wait() }()
+				select {
+				case <-time.After(5 * time.Second):
+					log.Warn("ChipDnaClient did not exit in time, killing...")
+					_ = cmd.Process.Kill()
+				case err := <-done:
+					log.Infof("ChipDnaClient exited cleanly: %v", err)
+				}
+			}
+			os.Exit(0)
+		}()
+	}
 
 	// Create App and wire routes
 	app := newApp(dispHandle, lockConn, config)

release notes.md

@@ -2,7 +2,11 @@
 
 builtVersion is a const in main.go
 
-#### 1.0.0 - 30 Jun 2024
+#### 1.0.1 - 22 July 2024
+added salto lock server and implemented workflow for Salto
+ 
+
+#### 1.0.0 - 30 June 2024
 added creditcall payment method 
  `/starttransaction` - API payment endpoint to start a transaction