Implement a basic smpp client

.gitignore

@@ -1,3 +1,4 @@
 jstester/node_modules
 encoding/tmp
 pdu/tmp
+tmp

client/client.go

@@ -1 +1,62 @@
-package client
+package client
+
+import (
+	"fmt"
+	"log"
+	"net"
+	"smpptester/pdu"
+)
+
+type SMPPClient struct {
+	Id   int
+	conn net.Conn
+	port string
+	log  log.Logger
+}
+
+func NewSMPPClient(port string, id int) *SMPPClient {
+	client := &SMPPClient{
+		Id:   id,
+		port: port,
+		log:  log.Logger{},
+	}
+	client.log = *log.New(log.Writer(), "", log.LstdFlags)
+	client.log.SetPrefix(fmt.Sprintf("SMPP client %d: ", client.Id))
+	return client
+}
+
+func (c *SMPPClient) Connect() error {
+	conn, err := net.Dial("tcp", c.port)
+	if err != nil {
+		return fmt.Errorf("failed to connect to SMPP server: %w", err)
+	}
+	c.log.Printf("SMPP client %d connected to %s", c.Id, c.port)
+	c.conn = conn
+	return nil
+}
+
+func (c *SMPPClient) Close() {
+	c.conn.Close()
+	c.log.Printf("SMPP client %d closed connection", c.Id)
+}
+
+func (c *SMPPClient) Send(pdata pdu.PDU) error {
+	if c.conn == nil {
+		return fmt.Errorf("connection is not established")
+	}
+
+	pdata.UpdateSize()
+	buf := pdu.ByteBufferPool.Get(pdata.Size())
+	err := pdata.Encode(buf)
+	if err != nil {
+		return fmt.Errorf("failed to encode PDU: %w", err)
+	}
+
+	_, err = c.conn.Write(buf.Bytes())
+	if err != nil {
+		return fmt.Errorf("failed to send PDU: %w", err)
+	}
+
+	c.log.Printf("SMPP client %d sent PDU: %+v", c.Id, pdata)
+	return nil
+}

main.go

@@ -4,9 +4,9 @@ import (
 	"bytes"
 	"encoding/binary"
 	"log"
-	"net"
 	"sync"
 
+	"smpptester/client"
 	"smpptester/pdu"
 )
 
@@ -166,47 +166,19 @@ func main() {
 	buf := pdu.ByteBufferPool.Get(submit.Size())
 	defer pdu.ByteBufferPool.Put(buf)
 	submit.Encode(buf)
-	log.Println(buf.Bytes())
-	log.Println(createSubmitSMPDU())
-	// log.Println(pdu.Encode())
-	// serviceType := "CMT"
-	// sourceAddrTON := byte(0x01)
-	// sourceAddrNPI := byte(0x01)
-	// sourceAddr := "12345"
-	// destAddrTON := byte(0x01)
-	// destAddrNPI := byte(0x01)
-	// destinationAddr := "67890"
-	// esmClass := byte(0x00)
-	// protocolID := byte(0x00)
-	// priorityFlag := byte(0x00)
-	// scheduleDeliveryTime := ""
-	// validityPeriod := ""
-	// registeredDelivery := byte(0x01)
-	// replaceIfPresentFlag := byte(0x00)
-	// dataCoding := byte(0x01)
-	// smDefaultMsgID := byte(0x00)
-	// shortMessage := "Hello, SMPP!"
 
 	wg := &sync.WaitGroup{}
 	wg.Add(1)
 
-	conn, err := net.Dial("tcp", "localhost:2775")
+	client := client.NewSMPPClient("localhost:2775", 1)
+	err := client.Connect()
 	if err != nil {
-		log.Printf("Failed to connect to SMPP server: %+v", err)
-		return
+		log.Fatalf("Failed to connect to SMPP server: %v", err)
+	}
+	err = client.Send(submit)
+	if err != nil {
+		log.Fatalf("Failed to send PDU: %v", err)
 	}
-	log.Printf("Connected to SMPP server")
-	defer conn.Close()
-
-	go func() {
-		conn.Write(buf.Bytes())
-		data, err := conn.Read(make([]byte, 1024))
-		if err != nil {
-			log.Printf("Failed to read from connection: %+v", err)
-			return
-		}
-		log.Printf("Received data: %#v", data)
-	}()
 
 	wg.Wait()
 }