Convert Switch command to be struct-based

command/switch.go

@@ -13,6 +13,7 @@ import (
 	"github.com/aws/aws-sdk-go-v2/config"
 	"github.com/aws/aws-sdk-go-v2/service/sts"
 	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
 )
 
 var (
@@ -42,45 +43,75 @@ This command will fail if you do not have active Cloud credentials.
 	Args:    cobra.ExactArgs(1),
 	Aliases: []string{"switch-account"},
 	RunE: func(cmd *cobra.Command, args []string) error {
-		outputType, _ := cmd.Flags().GetString(FlagOutputType)
-		shellType, _ := cmd.Flags().GetString(FlagShellType)
-		awsCliPath, _ := cmd.Flags().GetString(FlagAWSCLIPath)
-		if !slices.Contains(permittedOutputTypes, outputType) {
-			return ValueError{Value: outputType, ValidValues: permittedOutputTypes}
-		}
-
-		if !slices.Contains(permittedShellTypes, shellType) {
-			return ValueError{Value: shellType, ValidValues: permittedShellTypes}
+		var switchCmd SwitchCommand
+		if err := switchCmd.Parse(cmd.Flags(), args); err != nil {
+			return err
 		}
 
-		// We could read the environment variable for the assumed role ARN, but it might be expired which isn't very useful to the user.
-		var err error
-		var creds CloudCredentials
-		sessionName, _ := cmd.Flags().GetString(FlagRoleSessionName)
-
-		creds, err = getAWSCredentials(args[0], sessionName)
-		if err != nil {
-			// If this failed, either there was a network error or the user is not authorized to assume into this role
-			// This can happen if the user is not authenticated using the Bastion instance.
+		if err := switchCmd.Validate(); err != nil {
 			return err
 		}
 
-		switch outputType {
-		case outputTypeEnvironmentVariable:
-			creds.WriteFormat(os.Stdout, shellType)
-			return nil
-		case outputTypeAWSCredentialsFile:
-			acc := Account{ID: args[0], Name: args[0]}
-			newCliEntry := NewCloudCliEntry(creds, &acc)
-			return SaveCloudCredentialInCLI(awsCliPath, newCliEntry)
-		default:
-			return fmt.Errorf("%s is an invalid output type", outputType)
-		}
+		return switchCmd.Execute(cmd.Context())
 	},
 }
 
-func getAWSCredentials(accountID, roleSessionName string) (creds CloudCredentials, err error) {
-	ctx := context.Background()
+type SwitchCommand struct {
+	OutputType      string
+	ShellType       string
+	AWSCLIPath      string
+	RoleSessionName string
+	AccountID       string
+}
+
+func (s *SwitchCommand) Parse(flags *pflag.FlagSet, args []string) error {
+	s.OutputType, _ = flags.GetString(FlagOutputType)
+	s.ShellType, _ = flags.GetString(FlagShellType)
+	s.AWSCLIPath, _ = flags.GetString(FlagAWSCLIPath)
+	s.RoleSessionName, _ = flags.GetString(FlagRoleSessionName)
+	if len(args) == 0 {
+		return fmt.Errorf("account-id is required")
+	}
+
+	s.AccountID = args[0]
+	return nil
+}
+
+func (s SwitchCommand) Validate() error {
+	if !slices.Contains(permittedOutputTypes, s.OutputType) {
+		return ValueError{Value: s.OutputType, ValidValues: permittedOutputTypes}
+	}
+
+	if !slices.Contains(permittedShellTypes, s.ShellType) {
+		return ValueError{Value: s.ShellType, ValidValues: permittedShellTypes}
+	}
+
+	return nil
+}
+
+func (s SwitchCommand) Execute(ctx context.Context) error {
+	// We could read the environment variable for the assumed role ARN, but it might be expired which isn't very useful to the user.
+	creds, err := getAWSCredentials(ctx, s.AccountID, s.RoleSessionName)
+	if err != nil {
+		// If this failed, either there was a network error or the user is not authorized to assume into this role
+		// This can happen if the user is not authenticated using the Bastion instance.
+		return err
+	}
+
+	switch s.OutputType {
+	case outputTypeEnvironmentVariable:
+		creds.WriteFormat(os.Stdout, s.ShellType)
+		return nil
+	case outputTypeAWSCredentialsFile:
+		acc := Account{ID: s.AccountID, Name: s.AccountID}
+		newCliEntry := NewCloudCliEntry(creds, &acc)
+		return SaveCloudCredentialInCLI(s.AWSCLIPath, newCliEntry)
+	default:
+		return fmt.Errorf("%s is an invalid output type", s.OutputType)
+	}
+}
+
+func getAWSCredentials(ctx context.Context, accountID, roleSessionName string) (creds CloudCredentials, err error) {
 	cfg, err := config.LoadDefaultConfig(ctx)
 	if err != nil {
 		return