First commit with a basic mockserver for BeamNG stuff

cmd/cmd.go

@@ -0,0 +1,29 @@
+// Package cmd will be the CLI of our BeamNG OG mockserver
+package cmd
+
+import (
+	"os"
+
+	"github.com/spf13/cobra"
+)
+
+// rootCmd represents the base command when called without any subcommands
+var rootCmd = &cobra.Command{
+	Use:   "bngmock",
+	Short: "CLI for a BeamNG OG mockserver",
+	Long:  ``,
+}
+
+// Execute adds all child commands to the root command and sets flags appropriately.
+// This is called by main.main(). It only needs to happen once to the rootCmd.
+func Execute() {
+	err := rootCmd.Execute()
+	if err != nil {
+		os.Exit(1)
+	}
+}
+
+func init() {
+	rootCmd.PersistentFlags().StringP("address", "a", "127.0.0.1", "Address for the UDP server")
+	rootCmd.PersistentFlags().IntP("port", "p", 4444, "Port for the UDP server")
+}

cmd/replay.go

@@ -0,0 +1,35 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/ESilva15/BeamNGMockOg/mockserver"
+
+	"github.com/spf13/cobra"
+)
+
+func replayAction(cmd *cobra.Command, args []string) {
+	inputFile, _ := cmd.Flags().GetString("input")
+	address, _ := cmd.Flags().GetString("address")
+	port, _ := cmd.Flags().GetInt("port")
+
+	if err := mockserver.Replay(address, port, inputFile); err != nil {
+		fmt.Printf("Something went wrong while playing the file: %v", err)
+	}
+}
+
+// shelf
+var replayCmd = &cobra.Command{
+	Use:   "replay",
+	Short: "replay -i <path-to-bin-file>",
+	Long: `replay will store the data from the given UDP server to the 
+	filepath given by -i`,
+	Args: nil,
+	Run:  replayAction,
+}
+
+func init() {
+	rootCmd.AddCommand(replayCmd)
+
+	replayCmd.PersistentFlags().StringP("input", "i", "nofile.bin", "input file for serving")
+}

go.mod

@@ -0,0 +1,13 @@
+module github.com/ESilva15/BeamNGMockOg
+
+go 1.23.2
+
+require (
+	github.com/ESilva15/gobngsdk v0.0.2
+	github.com/spf13/cobra v1.10.1
+)
+
+require (
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/spf13/pflag v1.0.9 // indirect
+)

go.sum

@@ -0,0 +1,12 @@
+github.com/ESilva15/gobngsdk v0.0.2 h1:N6stNOE14Wg80BAZMFu/Qd9Qa/J0DmExCfdPoDf7lco=
+github.com/ESilva15/gobngsdk v0.0.2/go.mod h1:cKLaZRgM0tGGXDvosaSjHnxeyC5Y6rg7zCLqEUJnOzw=
+github.com/cpuguy83/go-md2man/v2 v2.0.6/go.mod h1:oOW0eioCTA6cOiMLiUPZOpcVxMig6NIQQ7OS05n1F4g=
+github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
+github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/spf13/cobra v1.10.1 h1:lJeBwCfmrnXthfAupyUTzJ/J4Nc1RsHC/mSRU2dll/s=
+github.com/spf13/cobra v1.10.1/go.mod h1:7SmJGaTHFVBY0jW4NXGluQoLvhqFQM+6XSKD+P4XaB0=
+github.com/spf13/pflag v1.0.9 h1:9exaQaMOCwffKiiiYk6/BndUBv+iRViNW+4lEMi0PvY=
+github.com/spf13/pflag v1.0.9/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

main.go

@@ -0,0 +1,7 @@
+package main
+
+import "github.com/ESilva15/BeamNGMockOg/cmd"
+
+func main() {
+	cmd.Execute()
+}

mockserver/replay.go

@@ -0,0 +1,54 @@
+// Package mockserver is the core of this program and it will have the API
+// to record binary data from the UDP server and then be able to mock it
+package mockserver
+
+import (
+	"bytes"
+	"encoding/binary"
+	"encoding/gob"
+	"log"
+	"os"
+	"time"
+
+	sdk "github.com/ESilva15/gobngsdk"
+)
+
+// Replay replays a given file <fp> in a UDP server <addr>:<port>
+func Replay(address string, port int, fp string) error {
+	bin, err := os.Open(fp)
+	if err != nil {
+		log.Fatal("error opening file:", err)
+	}
+
+	addr, conn, err := openUDPServer(address, port)
+	if err != nil {
+		return err
+	}
+
+	ticker := time.NewTicker(time.Second / 60)
+	defer ticker.Stop()
+
+	dec := gob.NewDecoder(bin)
+	for {
+		var og sdk.Outgauge
+		if err := dec.Decode(&og); err != nil {
+			log.Fatal("failed to read more data:", err)
+			break
+		}
+
+		buf := new(bytes.Buffer)
+		if err := binary.Write(buf, binary.LittleEndian, &og); err != nil {
+			log.Fatal("serialization failed:", err)
+			break
+		}
+
+		if _, err := conn.WriteToUDP(buf.Bytes(), addr); err != nil {
+			log.Fatal("send failed:", err)
+			break
+		}
+
+		<-ticker.C
+	}
+
+	return conn.Close()
+}

mockserver/server.go

@@ -0,0 +1,20 @@
+package mockserver
+
+import (
+	"fmt"
+	"net"
+)
+
+func openUDPServer(addr string, port int) (*net.UDPAddr, *net.UDPConn, error) {
+	udpAddr, err := net.ResolveUDPAddr("udp", fmt.Sprintf("%s:%d", addr, port))
+	if err != nil {
+		return nil, nil, err
+	}
+
+	conn, err := net.ListenUDP("udp", nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return udpAddr, conn, nil
+}