feat: adding REPL to command line tool (zurvan-lab#97)

.gitignore

@@ -30,3 +30,4 @@ Thumbs.db
 cmd/config.yaml
 /client
 log.ttrace
+build/

Makefile

@@ -6,6 +6,10 @@ devtools:
 	go install github.com/golangci/golangci-lint/cmd/golangci-lint@v1.54.1
 	go install mvdan.cc/gofumpt@latest
 
+## Building
+build-cli:
+	go build -o ./build/ttrace ./cmd/main.go
+
 ### Testing
 unit_test:
 	go test $(PACKAGES)

cmd/commands/repl.go

@@ -0,0 +1,75 @@
+package commands
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"net"
+	"os"
+	"strings"
+	"time"
+
+	cobra "github.com/spf13/cobra"
+)
+
+const PROMPT = "\n>> "
+
+func REPLCommand(parentCmd *cobra.Command) {
+	connect := &cobra.Command{
+		Use:   "connect",
+		Short: "Connects you to a time trace instance and you can interact with it in a REPL interface.",
+	}
+	parentCmd.AddCommand(connect)
+
+	address := connect.Flags().StringP("address", "a", "localhost:7070", "remote address of your time trace instance.")
+	username := connect.Flags().StringP("username", "u", "root", "username of the user you are going to connect with.")
+	password := connect.Flags().StringP("password", "p", "", "password of user trying to connect with.")
+
+	connect.Run = func(cmd *cobra.Command, args []string) {
+		conn, err := net.Dial("tcp", *address)
+		if err != nil {
+			dead(cmd, err)
+		}
+		defer conn.Close()
+
+		conQuery := fmt.Sprintf("CON %v %v", *username, *password)
+
+		response := do(conn, conQuery)
+		if response == "DONE" {
+			reader := bufio.NewReader(os.Stdin)
+
+			for {
+				fmt.Print(PROMPT)
+
+				input, _ := reader.ReadString('\n')
+				input = strings.TrimSuffix(input, "\n")
+
+				if input == "exit" {
+					break
+				}
+
+				cmd.Print(do(conn, input))
+			}
+		} else {
+			dead(cmd, errors.New(response)) //nolint
+		}
+	}
+}
+
+func do(conn net.Conn, q string) string {
+	resBuf := make([]byte, 1024)
+
+	_, err := conn.Write([]byte(q))
+	if err != nil {
+		return err.Error()
+	}
+
+	time.Sleep(time.Second * 1)
+
+	n, err := conn.Read(resBuf)
+	if err != nil {
+		return err.Error()
+	}
+
+	return string(resBuf[:n])
+}

cmd/main.go

@@ -8,11 +8,12 @@ import (
 
 func main() {
 	rootCmd := &cobra.Command{
-		Use:     "time-trace",
+		Use:     "ttrace",
 		Version: timetrace.StringVersion(),
 	}
 
 	commands.RunCommand(rootCmd)
+	commands.REPLCommand(rootCmd)
 
 	err := rootCmd.Execute()
 	if err != nil {

utils/errors/errors.go

@@ -10,4 +10,7 @@ var (
 
 	// server.
 	ErrAuth = errors.New("authentication error")
+
+	// CLI.
+	ErrInvalidUserOrPassword = errors.New("user or user information you provided is invalid")
 )