Implement basic TCP server

2 files changed, 59 insertions, 4 deletions

diff --git a/PROTOCOL.md b/PROTOCOL.md
index d17eded..6686036 100644
--- a/PROTOCOL.md
+++ b/PROTOCOL.md
@@ -12,6 +12,7 @@ Every packet starts with `uint8` denoting type of the rest of remaining data.
 | 0x01 | Handshake |
 | 0x02 | Ping      |
 | 0x03 | Pong      |
+| 0xFF | Test      |
 
 ## Events
 
@@ -38,3 +39,6 @@ Timezone should always be UTC.
 |--------|------|------------------|
 | uint64 | time | Unix timestamp   |
 
+### Test
+
+Event type reserved for testing. Does not have defined structure.
\ No newline at end of file
diff --git a/cmd/mock/main.go b/cmd/mock/main.go
index 8516821..88888f5 100644
--- a/cmd/mock/main.go
+++ b/cmd/mock/main.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"encoding/binary"
 	"flag"
 	"log"
 	"net"
@@ -8,11 +9,31 @@ import (
 
 var listenAddr string
 
+type Encoder interface {
+	Encode() []any
+}
+
+type Handshake struct {
+	ver uint8
+}
+
+func (h Handshake) Encode() []any {
+	return []any{h.ver}
+}
+
+type Test struct {
+	msg string
+}
+
+func (h Test) Encode() []any {
+	return []any{[]byte(h.msg)}
+}
+
 func main() {
 	flag.StringVar(&listenAddr, "a", "localhost:9999", "Listening address:port")
 	flag.Parse()
 
-	log.Print("Starting solec daemon mock")
+	log.Print("starting solec daemon mock")
 	log.Fatal(listen())
 }
 
@@ -22,17 +43,47 @@ func listen() error {
 		return err
 	}
 
-	log.Print("Server is listening on: ", listenAddr)
+	log.Print("server is listening on: ", listenAddr)
 
 	for {
 		conn, err := ln.Accept()
 		if err != nil {
-			log.Print("Cannot accept connection: ", err)
+			log.Print("cannot accept connection: ", err)
 		}
 		go handle(conn)
 	}
 }
 
 func handle(conn net.Conn) {
-	log.Print("Received connection from: ", conn.RemoteAddr())
+	log.Print("received connection from: ", conn.RemoteAddr())
+
+	hs := Handshake{
+		ver: 0x0,
+	}
+
+	if err := send(conn, 0x01, hs); err != nil {
+		log.Print("cannot send handshake ", err)
+		return
+	}
+
+	if err := send(conn, 0xFF, Test{msg: "solec kujawski jest zajebisty"}); err != nil {
+		log.Print("cannot send test message ", err)
+		return
+	}
+}
+
+func send(conn net.Conn, eType uint8, data Encoder) error {
+	err := binary.Write(conn, binary.BigEndian, eType)
+	if err != nil {
+		return err
+	}
+
+	for _, v := range data.Encode() {
+		err := binary.Write(conn, binary.BigEndian, v)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
 }