Fix build issue with server

Not useful yet... I thought it would be but I changed my mind...
Need to think about this a lot more

.gitea/workflows/benchmark.yaml

@@ -2,8 +2,7 @@ name: Benchmark BufferPool
 on:
   push:
     branches:
-      - '*'
-      - '!benchmark'
+      - 'master'
 
 jobs:
   RunBenchmarks:

.gitignore

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

client/client.go

@@ -1 +1,165 @@
-package client
+package client
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net"
+	"smpptester/pdu"
+	"smpptester/utils"
+	"time"
+
+	"golang.org/x/time/rate"
+)
+
+var (
+	SMPP_CLIENT_RETRY_TIMEOUT      = 1 * time.Second
+	SMPP_CLIENT_SEND_QUEUE_SIZE    = 1024 * 8
+	SMPP_CLIENT_RECEIVE_QUEUE_SIZE = 1024 * 8
+	SMPP_CLIENT_ASYNC_SEND_WORKERS = 16
+	SMPP_CLIENT_SEND_LIMIT         = 4
+)
+
+type SMPPClient struct {
+	Id           int
+	Connected    bool
+	SendQueue    chan pdu.PDU
+	ReceiveQueue chan pdu.PDU
+	SendLimit    *utils.ReactiveValue[int]
+
+	sendLimiter *rate.Limiter
+	enabled     bool
+	running     bool
+	conn        net.Conn
+	port        string
+	log         log.Logger
+	dcErr       chan (error)
+}
+
+func NewSMPPClient(port string, id int) *SMPPClient {
+	client := &SMPPClient{
+		Id:           id,
+		SendQueue:    make(chan pdu.PDU, SMPP_CLIENT_SEND_QUEUE_SIZE),
+		ReceiveQueue: make(chan pdu.PDU, SMPP_CLIENT_RECEIVE_QUEUE_SIZE),
+		SendLimit:    utils.NewReactiveValue[int](SMPP_CLIENT_SEND_LIMIT),
+
+		sendLimiter: rate.NewLimiter(rate.Limit(SMPP_CLIENT_SEND_LIMIT), SMPP_CLIENT_SEND_LIMIT),
+		port:        port,
+		log:         log.Logger{},
+		dcErr:       make(chan error, 128),
+	}
+	client.log = *log.New(log.Writer(), "", log.LstdFlags|log.Lshortfile)
+	client.log.SetPrefix(fmt.Sprintf("SMPP client %d: ", client.Id))
+
+	go func() {
+		limit := client.SendLimit.Subscribe()
+		defer client.SendLimit.Unsubscribe(limit)
+		for {
+			v := <-limit
+			client.log.Printf("Send limit changed to %d", *v)
+			client.sendLimiter.SetLimit(rate.Limit(*v))
+			client.sendLimiter.SetBurst(*v)
+		}
+	}()
+
+	return client
+}
+
+func (c *SMPPClient) Enable() {
+	if c.enabled {
+		c.log.Printf("SMPP client %d is already enabled", c.Id)
+		return
+	}
+	c.enabled = true
+	c.start()
+	c.log.Printf("SMPP client %d enabled", c.Id)
+}
+func (c *SMPPClient) Disable() {
+	if !c.enabled {
+		c.log.Printf("SMPP client %d is already disabled", c.Id)
+		return
+	}
+	c.enabled = false
+	c.dcErr <- fmt.Errorf("client is disabled")
+	if c.conn != nil {
+		c.conn.Close()
+	}
+	c.log.Printf("SMPP client %d disabled", c.Id)
+}
+
+func (c *SMPPClient) start() {
+	if c.running {
+		c.log.Printf("SMPP client %d is already running", c.Id)
+		return
+	}
+	go func() {
+		c.running = true
+		defer func() {
+			c.running = false
+		}()
+
+		c.log.Printf("SMPP client %d started", c.Id)
+		for {
+			if c.enabled && !c.Connected {
+				c.log.Printf("Trying to connect to %s", c.port)
+				err := c.connect()
+				if err != nil {
+					c.dcErr <- err
+				}
+			}
+			err := <-c.dcErr
+			c.Connected = false
+			if c.enabled {
+				c.log.Printf("Disconnected: '%v' trying again in %d second(s)", err, int(SMPP_CLIENT_RETRY_TIMEOUT.Seconds()))
+				time.Sleep(SMPP_CLIENT_RETRY_TIMEOUT)
+			} else {
+				c.log.Printf("Disconnected: '%v' & client is disabled, quitting", err)
+				break
+			}
+		}
+	}()
+}
+
+func (c *SMPPClient) connect() error {
+	if !c.enabled {
+		return fmt.Errorf("client is not enabled")
+	}
+	if c.Connected {
+		return fmt.Errorf("client is already connected")
+	}
+	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.Connected = true
+	c.conn = conn
+	return nil
+}
+
+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.sendLimiter.Wait(context.Background())
+	if err != nil {
+		return fmt.Errorf("failed to wait for rate limiter: %w", err)
+	}
+
+	_, err = c.conn.Write(buf.Bytes())
+	if err != nil {
+		c.dcErr <- err
+		return fmt.Errorf("failed to send PDU: %w", err)
+	}
+
+	// c.log.Printf("SMPP client %d sent PDU: %+v", c.Id, pdata)
+	return nil
+}

go.mod

@@ -2,4 +2,7 @@ module smpptester
 
 go 1.22.4
 
-require github.com/yuin/gopher-lua v1.1.1
+require (
+	github.com/yuin/gopher-lua v1.1.1
+	golang.org/x/time v0.5.0
+)

go.sum

@@ -1,2 +1,4 @@
 github.com/yuin/gopher-lua v1.1.1 h1:kYKnWBjvbNP4XLT3+bPEwAXJx262OhaHDWDVOPjL46M=
 github.com/yuin/gopher-lua v1.1.1/go.mod h1:GBR0iDaNXjAgGg9zfCvksxSRnQx76gclCIb7kdAd1Pw=
+golang.org/x/time v0.5.0 h1:o7cqy6amK/52YcAKIPlM3a+Fpj35zvRj2TP+e1xFSfk=
+golang.org/x/time v0.5.0/go.mod h1:3BpzKBy/shNhVucY/MWOyx10tF3SFh9QdLuxbVysPQM=

main.go

@@ -4,12 +4,15 @@ import (
 	"bytes"
 	"encoding/binary"
 	"log"
-	"net"
 	"sync"
+	"time"
+
+	"smpptester/client"
+	"smpptester/pdu"
 )
 
 func init() {
-	log.SetFlags(log.Lmicroseconds)
+	log.SetFlags(log.Lmicroseconds | log.Lshortfile)
 }
 
 // Function to create a submit_sm PDU
@@ -29,7 +32,7 @@ func createSubmitSMPDU() []byte {
 	validityPeriod := ""
 	registeredDelivery := byte(0x01)
 	replaceIfPresentFlag := byte(0x00)
-	dataCoding := byte(0x00)
+	dataCoding := byte(0x01)
 	smDefaultMsgID := byte(0x00)
 	shortMessage := "Hello, SMPP!"
 
@@ -37,7 +40,6 @@ func createSubmitSMPDU() []byte {
 	headerLength := 16
 	bodyLength := 1 + len(serviceType) + 1 + 1 + len(sourceAddr) + 1 + 1 + len(destinationAddr) + 1 + 1 + len(scheduleDeliveryTime) + 1 + len(validityPeriod) + 1 + 1 + 1 + 1 + 1 + len(shortMessage)
 	totalLength := headerLength + bodyLength
-	log.Printf("Total length: %d", totalLength)
 
 	// Create a buffer to hold the PDU
 	var buffer bytes.Buffer
@@ -136,28 +138,55 @@ func main() {
 	// 		go handleConnection(conn)
 	// 	}
 	// }()
-	log.Println(createSubmitSMPDU())
+	submit := &pdu.SUBMIT_SM{
+		Header: &pdu.PDU_HEADER{
+			Command_length:  0,
+			Command_id:      4,
+			Command_status:  0,
+			Sequence_number: 1,
+		},
+		Service_type:           "hehe",
+		Source_addr_ton:        0x01,
+		Source_addr_npi:        0x01,
+		Source_addr:            "12345",
+		Dest_addr_ton:          0x01,
+		Dest_addr_npi:          0x01,
+		Destination_addr:       "67890",
+		Esm_class:              0x00,
+		Protocol_id:            0x00,
+		Priority_flag:          0x00,
+		Schedule_delivery_time: "",
+		Validity_period:        "",
+		Registered_delivery:    0x01,
+		Replace_if_present:     0x00,
+		Data_coding:            0x01,
+		Sm_default_msg_id:      0x00,
+		Short_message:          "Hello, SMPP!",
+	}
+	submit.UpdateSize()
+	buf := pdu.ByteBufferPool.Get(submit.Size())
+	defer pdu.ByteBufferPool.Put(buf)
+	submit.Encode(buf)
 
 	wg := &sync.WaitGroup{}
 	wg.Add(1)
 
-	conn, err := net.Dial("tcp", "localhost:2775")
-	if err != nil {
-		log.Printf("Failed to connect to SMPP server: %+v", err)
-		return
-	}
-	log.Printf("Connected to SMPP server")
-	defer conn.Close()
-
-	go func() {
-		conn.Write(createSubmitSMPDU())
-		data, err := conn.Read(make([]byte, 1024))
-		if err != nil {
-			log.Printf("Failed to read from connection: %+v", err)
-			return
+	client := client.NewSMPPClient("localhost:2775", 1)
+	client.Enable()	
+	for {
+		if client.Connected {
+			// err := client.Send(submit)
+			// if err != nil {
+			// 	log.Printf("Failed to send PDU: %v", err)
+			// }
+			go client.Send(submit)
+			// if rand.Int() % 1000 == 0 {
+			// 	client.SendLimit.Set(rand.Int() % 1000)
+			// }
 		}
-		log.Printf("Received data: %#v", data)
-	}()
+		time.Sleep(500 * time.Millisecond)
+	}
+	log.Println("Are we done")
 
 	wg.Wait()
 }

pdu/bind.go

@@ -2,19 +2,19 @@ package pdu
 
 type (
 	BIND struct {
-		header            *PDU_HEADER
-		system_id         string
-		password          string
-		system_type       string
-		interface_version byte
-		addr_ton          byte
-		addr_npi          byte
-		address_range     string
+		Header            *PDU_HEADER
+		System_id         string
+		Password          string
+		System_type       string
+		Interface_version byte
+		Addr_ton          byte
+		Addr_npi          byte
+		Address_range     string
 	}
 	BIND_RESP struct {
-		header               *PDU_HEADER
-		system_id            string
-		sc_interface_version byte
+		Header               *PDU_HEADER
+		System_id            string
+		Sc_interface_version byte
 	}
 	BIND_RECVEIVER struct {
 		BIND
@@ -36,9 +36,9 @@ type (
 	}
 
 	UNBIND struct {
-		header *PDU_HEADER
+		Header *PDU_HEADER
 	}
 	UNBIND_RESP struct {
-		header *PDU_HEADER
+		Header *PDU_HEADER
 	}
 )

pdu/cancel.go

@@ -2,17 +2,17 @@ package pdu
 
 type (
 	CANCEL_SM struct {
-		header           *PDU_HEADER
-		service_type     string
-		message_id       string
-		source_addr_ton  byte
-		source_addr_npi  byte
-		source_addr      string
-		dest_addr_ton    byte
-		dest_addr_npi    byte
-		destination_addr string
+		Header           *PDU_HEADER
+		Service_type     string
+		Message_id       string
+		Source_addr_ton  byte
+		Source_addr_npi  byte
+		Source_addr      string
+		Dest_addr_ton    byte
+		Dest_addr_npi    byte
+		Destination_addr string
 	}
 	CANCEL_SM_RESP struct {
-		header *PDU_HEADER
+		Header *PDU_HEADER
 	}
 )

pdu/deliver.go

@@ -2,11 +2,11 @@ package pdu
 
 type (
 	DELIVER_SM struct {
-		header *PDU_HEADER
+		Header *PDU_HEADER
 		SUBMIT_SM
 	}
 	DELIVER_SM_RESP struct {
-		header *PDU_HEADER
+		Header *PDU_HEADER
 		SUBMIT_SM_RESP
 	}
 )

pdu/enquire.go

@@ -2,9 +2,9 @@ package pdu
 
 type (
 	ENQUIRE_LINK struct {
-		header *PDU_HEADER
+		Header *PDU_HEADER
 	}
 	ENQUIRE_LINK_RESP struct {
-		header *PDU_HEADER
+		Header *PDU_HEADER
 	}
 )

pdu/pdu.go

@@ -16,14 +16,14 @@ type (
 	}
 
 	PDU_HEADER struct {
-		command_length  uint32
-		command_id      uint32
-		command_status  uint32
-		sequence_number uint32
+		Command_length  uint32
+		Command_id      uint32
+		Command_status  uint32
+		Sequence_number uint32
 	}
 
 	GENERIC_NACK struct {
-		header *PDU_HEADER
+		Header *PDU_HEADER
 	}
 )
 
@@ -62,25 +62,25 @@ func (p *PDU_HEADER) Encode(buf *bytes.Buffer) error {
 	if buf == nil {
 		return fmt.Errorf("cannot encode into nil buffer")
 	}
-	binary.Write(buf, binary.BigEndian, p.command_length)
-	binary.Write(buf, binary.BigEndian, p.command_id)
-	binary.Write(buf, binary.BigEndian, p.command_status)
-	binary.Write(buf, binary.BigEndian, p.sequence_number)
+	binary.Write(buf, binary.BigEndian, p.Command_length)
+	binary.Write(buf, binary.BigEndian, p.Command_id)
+	binary.Write(buf, binary.BigEndian, p.Command_status)
+	binary.Write(buf, binary.BigEndian, p.Sequence_number)
 	return nil
 }
 func (p *PDU_HEADER) Decode(buf *bytes.Buffer) error {
 	if buf == nil {
 		return fmt.Errorf("cannot decode nil buffer")
 	}
-	binary.Read(buf, binary.BigEndian, &p.command_length)
-	binary.Read(buf, binary.BigEndian, &p.command_id)
-	binary.Read(buf, binary.BigEndian, &p.command_status)
-	binary.Read(buf, binary.BigEndian, &p.sequence_number)
+	binary.Read(buf, binary.BigEndian, &p.Command_length)
+	binary.Read(buf, binary.BigEndian, &p.Command_id)
+	binary.Read(buf, binary.BigEndian, &p.Command_status)
+	binary.Read(buf, binary.BigEndian, &p.Sequence_number)
 	return nil
 }
 func (p *PDU_HEADER) Size() int {
 	return 16
 }
 func (p *PDU_HEADER) UpdateSize() {
-	p.command_length = uint32(p.Size())
-}
+	p.Command_length = uint32(p.Size())
+}

pdu/pdu_test.go

@@ -11,10 +11,10 @@ import (
 // region encode
 func TestEncodeReturnsByteSliceOfLength16(t *testing.T) {
 	p := &PDU_HEADER{
-		command_length:  1,
-		command_id:      1,
-		command_status:  1,
-		sequence_number: 1,
+		Command_length:  1,
+		Command_id:      1,
+		Command_status:  1,
+		Sequence_number: 1,
 	}
 	buf := bytes.NewBuffer(make([]byte, 16))
 	buf.Reset()
@@ -30,10 +30,10 @@ func TestEncodeReturnsByteSliceOfLength16(t *testing.T) {
 
 func TestEncodeHandlesZeroValues(t *testing.T) {
 	p := &PDU_HEADER{
-		command_length:  0,
-		command_id:      0,
-		command_status:  0,
-		sequence_number: 0,
+		Command_length:  0,
+		Command_id:      0,
+		Command_status:  0,
+		Sequence_number: 0,
 	}
 	buf := bytes.NewBuffer(make([]byte, 16))
 	buf.Reset()
@@ -53,10 +53,10 @@ func TestEncodeHandlesZeroValues(t *testing.T) {
 
 func TestEncodeEncodesProperly(t *testing.T) {
 	p := &PDU_HEADER{
-		command_length:  1,
-		command_id:      2,
-		command_status:  3,
-		sequence_number: 4,
+		Command_length:  1,
+		Command_id:      2,
+		Command_status:  3,
+		Sequence_number: 4,
 	}
 	buf := bytes.NewBuffer(make([]byte, 16))
 	buf.Reset()
@@ -77,10 +77,10 @@ func TestEncodeEncodesProperly(t *testing.T) {
 
 func TestEncodeEncodesProperlyComplex(t *testing.T) {
 	p := &PDU_HEADER{
-		command_length:  13426724,
-		command_id:      254352,
-		command_status:  35634264,
-		sequence_number: 476543523,
+		Command_length:  13426724,
+		Command_id:      254352,
+		Command_status:  35634264,
+		Sequence_number: 476543523,
 	}
 	buf := bytes.NewBuffer(make([]byte, 16))
 	buf.Reset()
@@ -101,10 +101,10 @@ func TestEncodeEncodesProperlyComplex(t *testing.T) {
 
 func TestEncodeIntoCorrectlyEncodesFields(t *testing.T) {
 	p := &PDU_HEADER{
-		command_length:  16,
-		command_id:      1,
-		command_status:  0,
-		sequence_number: 12345,
+		Command_length:  16,
+		Command_id:      1,
+		Command_status:  0,
+		Sequence_number: 12345,
 	}
 	buf := bytes.NewBuffer(make([]byte, 16))
 	buf.Reset()
@@ -115,26 +115,26 @@ func TestEncodeIntoCorrectlyEncodesFields(t *testing.T) {
 	}
 
 	innerbuf := buf.Bytes()
-	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.command_length {
-		t.Errorf("Expected command_length %d, got %d", p.command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
+	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.Command_length {
+		t.Errorf("Expected command_length %d, got %d", p.Command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.command_id {
-		t.Errorf("Expected command_id %d, got %d", p.command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
+	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.Command_id {
+		t.Errorf("Expected command_id %d, got %d", p.Command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.command_status {
-		t.Errorf("Expected command_status %d, got %d", p.command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
+	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.Command_status {
+		t.Errorf("Expected command_status %d, got %d", p.Command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.sequence_number {
-		t.Errorf("Expected sequence_number %d, got %d", p.sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
+	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.Sequence_number {
+		t.Errorf("Expected sequence_number %d, got %d", p.Sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
 	}
 }
 
 func TestEncodeIntoHandlesLargerBuffer(t *testing.T) {
 	p := &PDU_HEADER{
-		command_length:  16,
-		command_id:      1,
-		command_status:  0,
-		sequence_number: 12345,
+		Command_length:  16,
+		Command_id:      1,
+		Command_status:  0,
+		Sequence_number: 12345,
 	}
 	buf := bytes.NewBuffer(make([]byte, 20)) // larger buffer size
 	buf.Reset()
@@ -145,26 +145,26 @@ func TestEncodeIntoHandlesLargerBuffer(t *testing.T) {
 	}
 
 	innerbuf := buf.Bytes()
-	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.command_length {
-		t.Errorf("Expected command_length %d, got %d", p.command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
+	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.Command_length {
+		t.Errorf("Expected command_length %d, got %d", p.Command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.command_id {
-		t.Errorf("Expected command_id %d, got %d", p.command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
+	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.Command_id {
+		t.Errorf("Expected command_id %d, got %d", p.Command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.command_status {
-		t.Errorf("Expected command_status %d, got %d", p.command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
+	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.Command_status {
+		t.Errorf("Expected command_status %d, got %d", p.Command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.sequence_number {
-		t.Errorf("Expected sequence_number %d, got %d", p.sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
+	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.Sequence_number {
+		t.Errorf("Expected sequence_number %d, got %d", p.Sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
 	}
 }
 
 func TestEncodeIntoUsesBigEndianEncoding(t *testing.T) {
 	p := &PDU_HEADER{
-		command_length:  16,
-		command_id:      1,
-		command_status:  0,
-		sequence_number: 12345,
+		Command_length:  16,
+		Command_id:      1,
+		Command_status:  0,
+		Sequence_number: 12345,
 	}
 	buf := bytes.NewBuffer(make([]byte, 16))
 	buf.Reset()
@@ -175,26 +175,26 @@ func TestEncodeIntoUsesBigEndianEncoding(t *testing.T) {
 	}
 
 	innerbuf := buf.Bytes()
-	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.command_length {
-		t.Errorf("Expected command_length %d, got %d", p.command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
+	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.Command_length {
+		t.Errorf("Expected command_length %d, got %d", p.Command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.command_id {
-		t.Errorf("Expected command_id %d, got %d", p.command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
+	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.Command_id {
+		t.Errorf("Expected command_id %d, got %d", p.Command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.command_status {
-		t.Errorf("Expected command_status %d, got %d", p.command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
+	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.Command_status {
+		t.Errorf("Expected command_status %d, got %d", p.Command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.sequence_number {
-		t.Errorf("Expected sequence_number %d, got %d", p.sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
+	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.Sequence_number {
+		t.Errorf("Expected sequence_number %d, got %d", p.Sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
 	}
 }
 
 func TestEncodeIntoConcurrencySafety(t *testing.T) {
 	p := &PDU_HEADER{
-		command_length:  16,
-		command_id:      1,
-		command_status:  0,
-		sequence_number: 12345,
+		Command_length:  16,
+		Command_id:      1,
+		Command_status:  0,
+		Sequence_number: 12345,
 	}
 	buf := bytes.NewBuffer(make([]byte, 16))
 	buf.Reset()
@@ -209,26 +209,26 @@ func TestEncodeIntoConcurrencySafety(t *testing.T) {
 	wg.Wait()
 
 	innerbuf := buf.Bytes()
-	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.command_length {
-		t.Errorf("Expected command_length %d, got %d", p.command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
+	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.Command_length {
+		t.Errorf("Expected command_length %d, got %d", p.Command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.command_id {
-		t.Errorf("Expected command_id %d, got %d", p.command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
+	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.Command_id {
+		t.Errorf("Expected command_id %d, got %d", p.Command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.command_status {
-		t.Errorf("Expected command_status %d, got %d", p.command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
+	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.Command_status {
+		t.Errorf("Expected command_status %d, got %d", p.Command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.sequence_number {
-		t.Errorf("Expected sequence_number %d, got %d", p.sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
+	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.Sequence_number {
+		t.Errorf("Expected sequence_number %d, got %d", p.Sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
 	}
 }
 
 func TestEncodeIntoWithMaximumValues(t *testing.T) {
 	p := &PDU_HEADER{
-		command_length:  math.MaxUint32,
-		command_id:      math.MaxUint32,
-		command_status:  math.MaxUint32,
-		sequence_number: math.MaxUint32,
+		Command_length:  math.MaxUint32,
+		Command_id:      math.MaxUint32,
+		Command_status:  math.MaxUint32,
+		Sequence_number: math.MaxUint32,
 	}
 	buf := bytes.NewBuffer(make([]byte, 16))
 	buf.Reset()
@@ -239,26 +239,26 @@ func TestEncodeIntoWithMaximumValues(t *testing.T) {
 	}
 
 	innerbuf := buf.Bytes()
-	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.command_length {
-		t.Errorf("Expected command_length %d, got %d", p.command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
+	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.Command_length {
+		t.Errorf("Expected command_length %d, got %d", p.Command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.command_id {
-		t.Errorf("Expected command_id %d, got %d", p.command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
+	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.Command_id {
+		t.Errorf("Expected command_id %d, got %d", p.Command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.command_status {
-		t.Errorf("Expected command_status %d, got %d", p.command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
+	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.Command_status {
+		t.Errorf("Expected command_status %d, got %d", p.Command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.sequence_number {
-		t.Errorf("Expected sequence_number %d, got %d", p.sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
+	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.Sequence_number {
+		t.Errorf("Expected sequence_number %d, got %d", p.Sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
 	}
 }
 
 func TestEncodeIntoWithBoundaryValues(t *testing.T) {
 	p := &PDU_HEADER{
-		command_length:  0,
-		command_id:      0,
-		command_status:  0,
-		sequence_number: 0,
+		Command_length:  0,
+		Command_id:      0,
+		Command_status:  0,
+		Sequence_number: 0,
 	}
 	buf := bytes.NewBuffer(make([]byte, 16))
 	buf.Reset()
@@ -269,17 +269,17 @@ func TestEncodeIntoWithBoundaryValues(t *testing.T) {
 	}
 
 	innerbuf := buf.Bytes()
-	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.command_length {
-		t.Errorf("Expected command_length %d, got %d", p.command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
+	if binary.BigEndian.Uint32(innerbuf[0:4]) != p.Command_length {
+		t.Errorf("Expected command_length %d, got %d", p.Command_length, binary.BigEndian.Uint32(innerbuf[0:4]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.command_id {
-		t.Errorf("Expected command_id %d, got %d", p.command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
+	if binary.BigEndian.Uint32(innerbuf[4:8]) != p.Command_id {
+		t.Errorf("Expected command_id %d, got %d", p.Command_id, binary.BigEndian.Uint32(innerbuf[4:8]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.command_status {
-		t.Errorf("Expected command_status %d, got %d", p.command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
+	if binary.BigEndian.Uint32(innerbuf[8:12]) != p.Command_status {
+		t.Errorf("Expected command_status %d, got %d", p.Command_status, binary.BigEndian.Uint32(innerbuf[8:12]))
 	}
-	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.sequence_number {
-		t.Errorf("Expected sequence_number %d, got %d", p.sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
+	if binary.BigEndian.Uint32(innerbuf[12:16]) != p.Sequence_number {
+		t.Errorf("Expected sequence_number %d, got %d", p.Sequence_number, binary.BigEndian.Uint32(innerbuf[12:16]))
 	}
 }
 
@@ -307,17 +307,17 @@ func TestDecodeParsesValidByteSlice(t *testing.T) {
 		t.Errorf("Expected no error, got %v", err)
 	}
 
-	if p.command_length != 16 {
-		t.Errorf("Expected command_length to be 16, got %d", p.command_length)
+	if p.Command_length != 16 {
+		t.Errorf("Expected command_length to be 16, got %d", p.Command_length)
 	}
-	if p.command_id != 1 {
-		t.Errorf("Expected command_id to be 1, got %d", p.command_id)
+	if p.Command_id != 1 {
+		t.Errorf("Expected command_id to be 1, got %d", p.Command_id)
 	}
-	if p.command_status != 2 {
-		t.Errorf("Expected command_status to be 2, got %d", p.command_status)
+	if p.Command_status != 2 {
+		t.Errorf("Expected command_status to be 2, got %d", p.Command_status)
 	}
-	if p.sequence_number != 3 {
-		t.Errorf("Expected sequence_number to be 3, got %d", p.sequence_number)
+	if p.Sequence_number != 3 {
+		t.Errorf("Expected sequence_number to be 3, got %d", p.Sequence_number)
 	}
 }
 
@@ -343,17 +343,17 @@ func TestDecodeHandlesNilDataInput(t *testing.T) {
 		t.Errorf("Expected error, got none")
 	}
 
-	if p.command_length != 0 {
-		t.Errorf("Expected command_length to be 0, got %d", p.command_length)
+	if p.Command_length != 0 {
+		t.Errorf("Expected command_length to be 0, got %d", p.Command_length)
 	}
-	if p.command_id != 0 {
-		t.Errorf("Expected command_id to be 0, got %d", p.command_id)
+	if p.Command_id != 0 {
+		t.Errorf("Expected command_id to be 0, got %d", p.Command_id)
 	}
-	if p.command_status != 0 {
-		t.Errorf("Expected command_status to be 0, got %d", p.command_status)
+	if p.Command_status != 0 {
+		t.Errorf("Expected command_status to be 0, got %d", p.Command_status)
 	}
-	if p.sequence_number != 0 {
-		t.Errorf("Expected sequence_number to be 0, got %d", p.sequence_number)
+	if p.Sequence_number != 0 {
+		t.Errorf("Expected sequence_number to be 0, got %d", p.Sequence_number)
 	}
 }
 
@@ -366,17 +366,17 @@ func TestDecodeHandlesEmptyByteSliceGracefully(t *testing.T) {
 		t.Errorf("Expected no error, got %v", err)
 	}
 
-	if p.command_length != 0 {
-		t.Errorf("Expected command_length to be 0, got %d", p.command_length)
+	if p.Command_length != 0 {
+		t.Errorf("Expected command_length to be 0, got %d", p.Command_length)
 	}
-	if p.command_id != 0 {
-		t.Errorf("Expected command_id to be 0, got %d", p.command_id)
+	if p.Command_id != 0 {
+		t.Errorf("Expected command_id to be 0, got %d", p.Command_id)
 	}
-	if p.command_status != 0 {
-		t.Errorf("Expected command_status to be 0, got %d", p.command_status)
+	if p.Command_status != 0 {
+		t.Errorf("Expected command_status to be 0, got %d", p.Command_status)
 	}
-	if p.sequence_number != 0 {
-		t.Errorf("Expected sequence_number to be 0, got %d", p.sequence_number)
+	if p.Sequence_number != 0 {
+		t.Errorf("Expected sequence_number to be 0, got %d", p.Sequence_number)
 	}
 }
 
@@ -408,11 +408,11 @@ func TestDecodeHandlesByteSlicesWithMaxUint32Values(t *testing.T) {
 		t.Errorf("Expected no error, got %v", err)
 	}
 
-	if p.command_length != math.MaxUint32 {
-		t.Errorf("Expected command_length to be %d, got %d", math.MaxUint32, p.command_length)
+	if p.Command_length != math.MaxUint32 {
+		t.Errorf("Expected command_length to be %d, got %d", math.MaxUint32, p.Command_length)
 	}
-	if p.command_id != math.MaxUint32 {
-		t.Errorf("Expected command_id to be %d, got %d", math.MaxUint32, p.command_id)
+	if p.Command_id != math.MaxUint32 {
+		t.Errorf("Expected command_id to be %d, got %d", math.MaxUint32, p.Command_id)
 	}
 }
 
@@ -425,11 +425,11 @@ func TestDecodeHandlesByteSlicesWithMinimumUint32Values(t *testing.T) {
 		t.Errorf("Expected no error, got %v", err)
 	}
 
-	if p.command_length != 0 {
-		t.Errorf("Expected command_length to be 0, got %d", p.command_length)
+	if p.Command_length != 0 {
+		t.Errorf("Expected command_length to be 0, got %d", p.Command_length)
 	}
-	if p.command_id != 0 {
-		t.Errorf("Expected command_id to be 0, got %d", p.command_id)
+	if p.Command_id != 0 {
+		t.Errorf("Expected command_id to be 0, got %d", p.Command_id)
 	}
 }
 
@@ -445,10 +445,10 @@ func TestSizeReturns16(t *testing.T) {
 // With buffer pool
 func BenchmarkEncodeWithBufferPool(b *testing.B) {
 	p := &PDU_HEADER{
-		command_length:  16,
-		command_id:      1,
-		command_status:  0,
-		sequence_number: 12345,
+		Command_length:  16,
+		Command_id:      1,
+		Command_status:  0,
+		Sequence_number: 12345,
 	}
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
@@ -461,10 +461,10 @@ func BenchmarkEncodeWithBufferPool(b *testing.B) {
 // Without buffer pool
 func BenchmarkEncodeWithoutBufferPool(b *testing.B) {
 	p := &PDU_HEADER{
-		command_length:  16,
-		command_id:      1,
-		command_status:  0,
-		sequence_number: 12345,
+		Command_length:  16,
+		Command_id:      1,
+		Command_status:  0,
+		Sequence_number: 12345,
 	}
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {

pdu/submit.go

@@ -10,25 +10,25 @@ import (
 
 type (
 	SUBMIT_SM struct {
-		header                 *PDU_HEADER
-		service_type           string
-		source_addr_ton        byte
-		source_addr_npi        byte
-		source_addr            string
-		dest_addr_ton          byte
-		dest_addr_npi          byte
-		destination_addr       string
-		esm_class              byte
-		protocol_id            byte
-		priority_flag          byte
-		schedule_delivery_time string
-		validity_period        string
-		registered_delivery    byte
-		replace_if_present     byte
-		data_coding            byte
-		sm_default_msg_id      byte
-		sm_length              byte
-		short_message          string
+		Header                 *PDU_HEADER
+		Service_type           string
+		Source_addr_ton        byte
+		Source_addr_npi        byte
+		Source_addr            string
+		Dest_addr_ton          byte
+		Dest_addr_npi          byte
+		Destination_addr       string
+		Esm_class              byte
+		Protocol_id            byte
+		Priority_flag          byte
+		Schedule_delivery_time string
+		Validity_period        string
+		Registered_delivery    byte
+		Replace_if_present     byte
+		Data_coding            byte
+		Sm_default_msg_id      byte
+		Sm_length              byte
+		Short_message          string
 		// user_message_reference uint16
 		// source_port               uint16
 		// source_addr_subunit       byte
@@ -59,12 +59,13 @@ type (
 		// ussd_service_op           byte
 	}
 	SUBMIT_SM_RESP struct {
-		header     *PDU_HEADER
-		message_id string
+		Header     *PDU_HEADER
+		Message_id string
 	}
 	SUBMIT_MULTI      struct{}
 	SUBMIT_MULTI_RESP struct{}
 )
+
 // See https://www.codeproject.com/Tips/470755/Encoding-Decoding-7-bit-User-Data-for-SMS-PDU-PDU
 // Another great site: https://doubleblak.com/blogPost.php?k=7bitpdu
 
@@ -74,31 +75,31 @@ func (p *SUBMIT_SM) Encode(buf *bytes.Buffer) error {
 	}
 	messageEncoder := p.GetEncoder()
 
-	p.header.Encode(buf)
+	p.Header.Encode(buf)
 	// These should be ASCII but UTF8 is a superset of ASCII so hopefully this'll be fine
-	buf.WriteString(p.service_type)
+	buf.WriteString(p.Service_type)
 	buf.Write(NULL_ARR)
-	binary.Write(buf, binary.BigEndian, p.source_addr_ton)
-	binary.Write(buf, binary.BigEndian, p.source_addr_npi)
-	buf.WriteString(p.source_addr)
+	binary.Write(buf, binary.BigEndian, p.Source_addr_ton)
+	binary.Write(buf, binary.BigEndian, p.Source_addr_npi)
+	buf.WriteString(p.Source_addr)
 	buf.Write(NULL_ARR)
-	binary.Write(buf, binary.BigEndian, p.dest_addr_ton)
-	binary.Write(buf, binary.BigEndian, p.dest_addr_npi)
-	buf.WriteString(p.destination_addr)
+	binary.Write(buf, binary.BigEndian, p.Dest_addr_ton)
+	binary.Write(buf, binary.BigEndian, p.Dest_addr_npi)
+	buf.WriteString(p.Destination_addr)
 	buf.Write(NULL_ARR)
-	binary.Write(buf, binary.BigEndian, p.esm_class)
-	binary.Write(buf, binary.BigEndian, p.protocol_id)
-	binary.Write(buf, binary.BigEndian, p.priority_flag)
-	buf.WriteString(p.schedule_delivery_time)
+	binary.Write(buf, binary.BigEndian, p.Esm_class)
+	binary.Write(buf, binary.BigEndian, p.Protocol_id)
+	binary.Write(buf, binary.BigEndian, p.Priority_flag)
+	buf.WriteString(p.Schedule_delivery_time)
 	buf.Write(NULL_ARR)
-	buf.WriteString(p.validity_period)
+	buf.WriteString(p.Validity_period)
 	buf.Write(NULL_ARR)
-	binary.Write(buf, binary.BigEndian, p.registered_delivery)
-	binary.Write(buf, binary.BigEndian, p.replace_if_present)
-	binary.Write(buf, binary.BigEndian, p.data_coding)
-	binary.Write(buf, binary.BigEndian, p.sm_default_msg_id)
-	binary.Write(buf, binary.BigEndian, p.sm_length)
-	err := messageEncoder.Encode(&p.short_message, buf)
+	binary.Write(buf, binary.BigEndian, p.Registered_delivery)
+	binary.Write(buf, binary.BigEndian, p.Replace_if_present)
+	binary.Write(buf, binary.BigEndian, p.Data_coding)
+	binary.Write(buf, binary.BigEndian, p.Sm_default_msg_id)
+	binary.Write(buf, binary.BigEndian, p.Sm_length)
+	err := messageEncoder.Encode(&p.Short_message, buf)
 	if err != nil {
 		return err
 	}
@@ -112,33 +113,33 @@ func (p *SUBMIT_SM) Decode(buf *bytes.Buffer) error {
 }
 func (p *SUBMIT_SM) Size() int {
 	var size int
-	size += p.header.Size()
-	size += 1 + len(p.service_type)
+	size += p.Header.Size()
+	size += 1 + len(p.Service_type)
 	size += 1 // source_addr_ton
 	size += 1 // source_addr_npi
-	size += 1 + len(p.source_addr)
+	size += 1 + len(p.Source_addr)
 	size += 1 // dest_addr_ton
 	size += 1 // dest_addr_npi
-	size += 1 + len(p.destination_addr)
+	size += 1 + len(p.Destination_addr)
 	size += 1 // esm_class
 	size += 1 // protocol_id
 	size += 1 // priority_flag
-	size += 1 + len(p.schedule_delivery_time)
-	size += 1 + len(p.validity_period)
+	size += 1 + len(p.Schedule_delivery_time)
+	size += 1 + len(p.Validity_period)
 	size += 1 // registered_delivery
 	size += 1 // replace_if_present
 	size += 1 // data_coding
 	size += 1 // sm_default_msg_id
 	size += 1 // sm_length
-	size += p.GetEncoder().EncodesInto(&p.short_message)
+	size += p.GetEncoder().EncodesInto(&p.Short_message)
 	return size
 }
 func (p *SUBMIT_SM) UpdateSize() {
-	p.header.command_length = uint32(p.Size())
-	p.sm_length = byte(p.GetEncoder().EncodesInto(&p.short_message))
+	p.Header.Command_length = uint32(p.Size())
+	p.Sm_length = byte(p.GetEncoder().EncodesInto(&p.Short_message))
 }
 func (p *SUBMIT_SM) GetEncoder() encoding.Coder {
-	switch p.data_coding {
+	switch p.Data_coding {
 	case 0b00000000: // GSM7
 		return &encoding.GSM7Coder{}
 	case 0b00000001: // ASCII

pdu/submit_test.go

@@ -9,28 +9,28 @@ import (
 // See examples: https://www.openmarket.com/docs/Content/apis/v4smpp/mt-examples.htm
 func TestEncodeFunctionCorrectlyEncodesAllFields(t *testing.T) {
 	p := &SUBMIT_SM{
-		header: &PDU_HEADER{
-			command_length:  0,
-			command_id:      4,
-			command_status:  0,
-			sequence_number: 378019,
+		Header: &PDU_HEADER{
+			Command_length:  0,
+			Command_id:      4,
+			Command_status:  0,
+			Sequence_number: 378019,
 		},
-		service_type:           "OMV4",
-		source_addr_ton:        3,
-		source_addr_npi:        1,
-		source_addr:            "80362",
-		dest_addr_ton:          1,
-		dest_addr_npi:          1,
-		destination_addr:       "812345001000",
-		esm_class:              0,
-		protocol_id:            0,
-		priority_flag:          0,
-		schedule_delivery_time: "",
-		validity_period:        "180105120000004+",
-		registered_delivery:    1,
-		data_coding:            1, // The example uses 0 and claims to use GSM but the message is encoded as ASCII...
-		sm_default_msg_id:      0,
-		short_message:          "Reply Yes to opt in or No to opt out.",
+		Service_type:           "OMV4",
+		Source_addr_ton:        3,
+		Source_addr_npi:        1,
+		Source_addr:            "80362",
+		Dest_addr_ton:          1,
+		Dest_addr_npi:          1,
+		Destination_addr:       "812345001000",
+		Esm_class:              0,
+		Protocol_id:            0,
+		Priority_flag:          0,
+		Schedule_delivery_time: "",
+		Validity_period:        "180105120000004+",
+		Registered_delivery:    1,
+		Data_coding:            1, // The example uses 0 and claims to use GSM but the message is encoded as ASCII...
+		Sm_default_msg_id:      0,
+		Short_message:          "Reply Yes to opt in or No to opt out.",
 	}
 	p.UpdateSize()
 	buf := ByteBufferPool.Get(p.Size())
@@ -47,28 +47,28 @@ func TestEncodeFunctionCorrectlyEncodesAllFields(t *testing.T) {
 
 func TestEncodeFunctionCorrectlyEncodesAllFieldsGSM7Message(t *testing.T) {
 	p := &SUBMIT_SM{
-		header: &PDU_HEADER{
-			command_length:  0,
-			command_id:      4,
-			command_status:  0,
-			sequence_number: 378019,
+		Header: &PDU_HEADER{
+			Command_length:  0,
+			Command_id:      4,
+			Command_status:  0,
+			Sequence_number: 378019,
 		},
-		service_type:           "OMV4",
-		source_addr_ton:        3,
-		source_addr_npi:        1,
-		source_addr:            "80362",
-		dest_addr_ton:          1,
-		dest_addr_npi:          1,
-		destination_addr:       "812345001000",
-		esm_class:              0,
-		protocol_id:            0,
-		priority_flag:          0,
-		schedule_delivery_time: "",
-		validity_period:        "180105120000004+",
-		registered_delivery:    1,
-		data_coding:            0, // The example uses 0 and claims to use GSM but the message is encoded as ASCII...
-		sm_default_msg_id:      0,
-		short_message:          "Reply Yes to opt in or No to opt out.",
+		Service_type:           "OMV4",
+		Source_addr_ton:        3,
+		Source_addr_npi:        1,
+		Source_addr:            "80362",
+		Dest_addr_ton:          1,
+		Dest_addr_npi:          1,
+		Destination_addr:       "812345001000",
+		Esm_class:              0,
+		Protocol_id:            0,
+		Priority_flag:          0,
+		Schedule_delivery_time: "",
+		Validity_period:        "180105120000004+",
+		Registered_delivery:    1,
+		Data_coding:            0, // The example uses 0 and claims to use GSM but the message is encoded as ASCII...
+		Sm_default_msg_id:      0,
+		Short_message:          "Reply Yes to opt in or No to opt out.",
 	}
 	p.UpdateSize()
 	buf := ByteBufferPool.Get(p.Size())
@@ -88,13 +88,13 @@ func TestEncodeFunctionCorrectlyEncodesAllFieldsGSM7Message(t *testing.T) {
 // region size
 func TestCalculateSizeTypicalInstance(t *testing.T) {
 	p := &SUBMIT_SM{
-		service_type:           "test_service",
-		source_addr:            "12345",
-		destination_addr:       "67890",
-		schedule_delivery_time: "",
-		validity_period:        "",
-		short_message:          "Hello, World!",
-		data_coding:            1,
+		Service_type:           "test_service",
+		Source_addr:            "12345",
+		Destination_addr:       "67890",
+		Schedule_delivery_time: "",
+		Validity_period:        "",
+		Short_message:          "Hello, World!",
+		Data_coding:            1,
 	}
 	expectedSize := 68
 	actualSize := p.Size()
@@ -105,13 +105,13 @@ func TestCalculateSizeTypicalInstance(t *testing.T) {
 
 func TestCalculateSizeTypicalGSM7Instance(t *testing.T) {
 	p := &SUBMIT_SM{
-		service_type:           "test_service",
-		source_addr:            "12345",
-		destination_addr:       "67890",
-		schedule_delivery_time: "",
-		validity_period:        "",
-		short_message:          "Hello, World!",
-		data_coding:            0,
+		Service_type:           "test_service",
+		Source_addr:            "12345",
+		Destination_addr:       "67890",
+		Schedule_delivery_time: "",
+		Validity_period:        "",
+		Short_message:          "Hello, World!",
+		Data_coding:            0,
 	}
 	expectedSize := 67
 	actualSize := p.Size()
@@ -123,13 +123,13 @@ func TestCalculateSizeTypicalGSM7Instance(t *testing.T) {
 func TestCalculateSizeMaxLengths(t *testing.T) {
 	maxLen := 255
 	p := &SUBMIT_SM{
-		service_type:           string(make([]byte, maxLen)),
-		source_addr:            string(make([]byte, maxLen)),
-		destination_addr:       string(make([]byte, maxLen)),
-		schedule_delivery_time: string(make([]byte, maxLen)),
-		validity_period:        string(make([]byte, maxLen)),
-		short_message:          string(make([]byte, maxLen)),
-		data_coding:            1,
+		Service_type:           string(make([]byte, maxLen)),
+		Source_addr:            string(make([]byte, maxLen)),
+		Destination_addr:       string(make([]byte, maxLen)),
+		Schedule_delivery_time: string(make([]byte, maxLen)),
+		Validity_period:        string(make([]byte, maxLen)),
+		Short_message:          string(make([]byte, maxLen)),
+		Data_coding:            1,
 	}
 	expectedSize := 1563
 	actualSize := p.Size()
@@ -140,12 +140,12 @@ func TestCalculateSizeMaxLengths(t *testing.T) {
 
 func TestHandlesEmptyStringsForAllStringFields(t *testing.T) {
 	p := &SUBMIT_SM{
-		service_type:           "",
-		source_addr:            "",
-		destination_addr:       "",
-		schedule_delivery_time: "",
-		validity_period:        "",
-		short_message:          "",
+		Service_type:           "",
+		Source_addr:            "",
+		Destination_addr:       "",
+		Schedule_delivery_time: "",
+		Validity_period:        "",
+		Short_message:          "",
 	}
 	expectedSize := 33
 	actualSize := p.Size()

server/server.go

@@ -1 +1,66 @@
-package server
+package server
+
+import (
+	"fmt"
+	"log"
+	"net"
+)
+
+type SMPPServer struct {
+	Id int
+	conns []*net.Conn
+	listener net.Listener
+	port  string
+	log log.Logger
+}
+
+func NewSMPPServer(port string, id int) *SMPPServer {
+	server := &SMPPServer{
+		port: port,
+		log: log.Logger{},
+		Id: id,
+	}
+	server.log = *log.New(log.Writer(), "", log.LstdFlags)
+	server.log.SetPrefix(fmt.Sprintf("SMPP server %d: ", server.Id))
+	return server
+}
+
+func (s *SMPPServer) Listen() error {
+	listener, err := net.Listen("tcp", s.port)
+	if err != nil {
+		return fmt.Errorf("failed to start SMPP server: %w", err)
+	}
+	// s.log.Printf("SMPP server %d started on %s", s.port)
+	s.listener = listener
+	return nil
+}
+
+// package main
+
+// import (
+// 	"net"
+// 	"fmt"
+// )
+
+// func main() {
+// 	ln, err := net.Listen("tcp", ":8080")
+// 	if err != nil {
+// 		fmt.Println(err)
+// 		return
+// 	}
+// 	defer ln.Close()
+
+// 	for {
+// 		conn, err := ln.Accept()
+// 		if err != nil {
+// 			fmt.Println(err)
+// 			continue
+// 		}
+// 		go handleConnection(conn)
+// 	}
+// }
+
+// func handleConnection(conn net.Conn) {
+// 	defer conn.Close()
+// 	// Handle the connection
+// }

utils/reactivevalue.go

@@ -0,0 +1,36 @@
+package utils
+
+type ReactiveValue[T any] struct {
+	V       T
+	subscribers []chan *T
+}
+
+func NewReactiveValue[T any](value T) *ReactiveValue[T] {
+	return &ReactiveValue[T]{
+		V:       value,
+		subscribers: make([]chan *T, 0),
+	}
+}
+
+func (rv *ReactiveValue[T]) Set(value T) {
+	rv.V = value
+	for _, subscriber := range rv.subscribers {
+		subscriber <- &value
+	}
+}
+
+func (rv *ReactiveValue[T]) Subscribe() chan *T {
+	subscriber := make(chan *T)
+	rv.subscribers = append(rv.subscribers, subscriber)
+	return subscriber
+}
+
+func (rv *ReactiveValue[T]) Unsubscribe(subscriber chan *T) {
+	for i, s := range rv.subscribers {
+		if s == subscriber {
+			rv.subscribers = append(rv.subscribers[:i], rv.subscribers[i+1:]...)
+			close(subscriber)
+			return
+		}
+	}
+}