Merge pull request #14 from rog-golang-buddies/whutchinson98/feat/sta…

…rter-commands

feat: Set up basic commands that are called from cmd/main.go

cmd/main.go

@@ -5,6 +5,7 @@ import (
 	"os"
 
 	"github.com/rog-golang-buddies/go-automatic-apps/internal/parser"
+	cmd "github.com/rog-golang-buddies/go-automatic-apps/pkg/commands"
 )
 
 func main() {
@@ -14,6 +15,19 @@ func main() {
 		panic(err)
 	}
 
-	fmt.Printf("CLI Commands: %v\n", commands)
-	fmt.Printf("CLI Flags: %v\n", flags)
+	baseCommand := commands[0]
+	subCommands := commands[1:]
+
+	switch baseCommand {
+	case "help":
+		err = cmd.HelpCommand.Run(&subCommands, &flags)
+	case "version":
+		err = cmd.VersionCommand.Run(&subCommands, &flags)
+	default:
+		panic(fmt.Errorf("no command matches %v", baseCommand))
+	}
+
+	if err != nil {
+		panic(fmt.Errorf("error executing command %v", err))
+	}
 }

internal/parser/parse_cli.go

@@ -74,5 +74,9 @@ func ParseCliArguments(arguments []string) ([]string, map[string]interface{}, er
 		flags[flag] = true
 	}
 
+	if len(commands) == 0 {
+		return nil, nil, fmt.Errorf("no commands were provided")
+	}
+
 	return commands, flags, nil
 }

internal/parser/parse_cli_test.go

@@ -97,5 +97,17 @@ func TestParseCliArguments(t *testing.T) {
 			t.Fatalf("Error message incorrect. Expected \"%v\" got \"%v\"", "empty flag was passed in", err.Error())
 		}
 	})
+	t.Run("Errors if no commands were passed in", func(t *testing.T) {
+		_, _, err := ParseCliArguments([]string{"--foo", "bar"})
+
+		if err == nil {
+			t.Fatalf("Error was expected but not received")
+		}
+
+		if err.Error() != "no commands were provided" {
+			t.Fatalf("Error message incorrect. Expected \"%v\" got \"%v\"", "no commands were provided", err.Error())
+		}
+
+	})
 
 }

pkg/commands/commands.go

@@ -0,0 +1,7 @@
+package commands
+
+type BaseCommand struct {
+	Name        string
+	Description string
+	Run         func(commands *[]string, flags *map[string]interface{}) error
+}

pkg/commands/help.go

@@ -0,0 +1,20 @@
+package commands
+
+import "fmt"
+
+var HelpCommand = BaseCommand{
+	Name:        "help",
+	Description: "Provides list of all commands",
+	Run:         helpCommand,
+}
+
+func helpCommand(commands *[]string, flags *map[string]interface{}) error {
+	// We have to "remake" the help command otherwise we get a runtime cycle error
+	commandsList := []BaseCommand{{Name: "help", Description: "Provides list of all commands"}, VersionCommand}
+
+	for _, command := range commandsList {
+		fmt.Printf("[%v]: %v\n", command.Name, command.Description)
+	}
+
+	return nil
+}

pkg/commands/version.go

@@ -0,0 +1,19 @@
+package commands
+
+import (
+	"fmt"
+	"runtime"
+)
+
+var VersionCommand = BaseCommand{
+	Name:        "version",
+	Description: "Provides useful information about go environment",
+	Run:         versionCommand,
+}
+
+func versionCommand(commands *[]string, flags *map[string]interface{}) error {
+	fmt.Printf("Go Version: %v\n", runtime.Version())
+	fmt.Printf("GAA: %v\n", runtime.GOARCH)
+	fmt.Printf("GOOS: %v\n", runtime.GOOS)
+	return nil
+}