feat: add flags to cli command

cmd/celestia-da/main.go

@@ -2,49 +2,86 @@ package main
 
 import (
 	"context"
+	"encoding/hex"
 	"errors"
 	rpc "github.com/celestiaorg/celestia-node/api/rpc/client"
 	"github.com/celestiaorg/celestia-node/share"
+	"github.com/spf13/cobra"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials/insecure"
 	"log"
 	"net"
+	"os"
 
 	"github.com/rollkit/celestia-da"
 	"github.com/rollkit/go-da/proxy"
 )
 
 func main() {
-	// TODO: potential configuration options:
-	//  - options to configure Celestia Client
-	//    - address
-	//    - token
-	//    - namespace
-	//    - height (?)
-	//  - options to configure gRPC server (encryption, any other)
-	//  - options for listener (network, unix sokcet?)
-
-	rpcAddress := "127.0.0.1:"
+	// TODO(tzdybal): extract configuration and mainCmd from main func
+	// TODO(tzdybal): read configuration from file (with viper)
+	rpcAddress := "http://127.0.0.1:26658"
 	rpcToken := ""
-	rpcNamespace := []byte("test")
+	namespace := ""
 
+	listenAddress := "0.0.0.0:0"
+	listenNetwork := "tcp"
+
+	rootCmd := &cobra.Command{
+		Use:   "celestia-da",
+		Short: "Celesia DA layer gRPC server for rollkit",
+		Run: func(cmd *cobra.Command, args []string) {
+			// Working with OutOrStdout/OutOrStderr allows us to unit test our command easier
+			serve(rpcAddress, rpcToken, namespace)
+		},
+	}
+
+	rootCmd.Flags().StringVar(&rpcAddress, "rpc.address", rpcAddress, "celestia-node RPC endpoint address")
+	rootCmd.Flags().StringVar(&rpcToken, "rpc.token", "", "celestia-node RPC auth token")
+	rootCmd.Flags().StringVar(&namespace, "namespace", "", "celestia namespace to use (hex encoded)")
+	rootCmd.Flags().StringVar(&listenAddress, "listen.address", listenAddress,
+		"Listen address")
+	rootCmd.Flags().StringVar(&listenNetwork, "listen.network", listenNetwork,
+		"Listen network type must be \"tcp\", \"tcp4\", \"tcp6\", \"unix\" or \"unixpacket\"")
+
+	if err := rootCmd.MarkFlagRequired("rpc.token"); err != nil {
+		log.Fatal("token:", err)
+	}
+
+	if err := rootCmd.MarkFlagRequired("namespace"); err != nil {
+		log.Fatal("namespace:", err)
+	}
+
+	if err := rootCmd.Execute(); err != nil {
+		os.Exit(1)
+	}
+}
+
+func serve(rpcAddress string, rpcToken string, nsString string) {
 	ctx := context.Background()
 	client, err := rpc.NewClient(ctx, rpcAddress, rpcToken)
 	if err != nil {
 		log.Fatalln("failed to create celestia-node RPC client:", err)
 	}
-	namespace, err := share.NewBlobNamespaceV0(rpcNamespace)
+	nsBytes := make([]byte, len(nsString)/2)
+	_, err = hex.Decode(nsBytes, []byte(nsString))
+	if err != nil {
+		log.Fatalln("invalid hex value of a namespace:", err)
+	}
+	namespace, err := share.NewBlobNamespaceV0(nsBytes)
 	if err != nil {
 		log.Fatalln("invalid namespace:", err)
 	}
 
 	da := celestia.NewCelestiaDA(client, namespace, ctx)
+	// TODO(tzdybal): add configuration options for encryption
 	srv := proxy.NewServer(da, grpc.Creds(insecure.NewCredentials()))
 
 	lis, err := net.Listen("tcp", "")
 	if err != nil {
 		log.Fatalln("failed to create network listener:", err)
 	}
+	log.Println("serving celestia-da over gRPC on:", lis.Addr())
 	err = srv.Serve(lis)
 	if !errors.Is(err, grpc.ErrServerStopped) {
 		log.Fatalln("gRPC server stopped with error:", err)