Prevent overwriting already existing files

internal/cli/terraform.go

@@ -16,6 +16,7 @@ import (
 	"github.com/spf13/cobra"
 
 	"github.com/auth0/auth0-cli/internal/auth0"
+	"github.com/auth0/auth0-cli/internal/prompt"
 )
 
 var tfFlags = terraformFlags{
@@ -76,6 +77,7 @@ func generateTerraformCmd(cli *cli) *cobra.Command {
 		RunE: generateTerraformCmdRun(cli, &inputs),
 	}
 
+	cmd.Flags().BoolVar(&cli.force, "force", false, "Skip confirmation.")
 	tfFlags.OutputDIR.RegisterString(cmd, &inputs.OutputDIR, "./")
 
 	return cmd
@@ -88,6 +90,16 @@ func generateTerraformCmdRun(cli *cli, inputs *terraformInputs) func(cmd *cobra.
 			return err
 		}
 
+		cli.renderer.JSONResult(data)
+
+		if !checkOutputDirectoryIsEmpty(cli, inputs.OutputDIR) {
+			return nil
+		}
+
+		if err := cleanOutputDirectory(inputs.OutputDIR); err != nil {
+			return err
+		}
+
 		if err := generateTerraformImportConfig(inputs.OutputDIR, data); err != nil {
 			return err
 		}
@@ -260,3 +272,49 @@ func terraformProviderCredentialsAreAvailable() bool {
 
 	return (domain != "" && clientID != "" && clientSecret != "") || (domain != "" && apiToken != "")
 }
+
+func checkOutputDirectoryIsEmpty(cli *cli, outputDIR string) bool {
+	_, err := os.Stat(outputDIR)
+	if os.IsNotExist(err) {
+		return true
+	}
+
+	_, mainFileErr := os.Stat(path.Join(outputDIR, "main.tf"))
+	_, importFileErr := os.Stat(path.Join(outputDIR, "auth0_import.tf"))
+	_, generatedFileErr := os.Stat(path.Join(outputDIR, "generated.tf"))
+	if os.IsNotExist(mainFileErr) && os.IsNotExist(importFileErr) && os.IsNotExist(generatedFileErr) {
+		return true
+	}
+
+	cli.renderer.Warnf(
+		"Output directory %q is not empty. "+
+			"Proceeding will overwrite the main.tf, auth0_import.tf and generated.tf files.",
+		outputDIR,
+	)
+
+	if !cli.force && !cli.noInput {
+		if confirmed := prompt.Confirm("Are you sure you want to proceed?"); !confirmed {
+			return false
+		}
+	}
+
+	return true
+}
+
+func cleanOutputDirectory(outputDIR string) error {
+	var joinedErrors error
+
+	if err := os.Remove(path.Join(outputDIR, "main.tf")); err != nil && !os.IsNotExist(err) {
+		joinedErrors = errors.Join(err)
+	}
+
+	if err := os.Remove(path.Join(outputDIR, "auth0_import.tf")); err != nil && !os.IsNotExist(err) {
+		joinedErrors = errors.Join(err)
+	}
+
+	if err := os.Remove(path.Join(outputDIR, "generated.tf")); err != nil && !os.IsNotExist(err) {
+		joinedErrors = errors.Join(err)
+	}
+
+	return joinedErrors
+}

internal/cli/terraform_test.go

@@ -12,6 +12,8 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+
+	"github.com/auth0/auth0-cli/internal/display"
 )
 
 type mockFetcher struct {
@@ -259,3 +261,89 @@ func TestTerraformProviderCredentialsAreAvailable(t *testing.T) {
 		})
 	}
 }
+
+func TestCheckOutputDirectoryIsEmpty(t *testing.T) {
+	t.Run("it returns true if the directory is empty", func(t *testing.T) {
+		tempDIR := t.TempDir()
+
+		isEmpty := checkOutputDirectoryIsEmpty(&cli{}, tempDIR)
+		assert.True(t, isEmpty)
+	})
+
+	t.Run("it returns true if the directory doesn't exist", func(t *testing.T) {
+		isEmpty := checkOutputDirectoryIsEmpty(&cli{}, "")
+		assert.True(t, isEmpty)
+	})
+
+	t.Run("it returns true if the directory is not empty but we're forcing the command", func(t *testing.T) {
+		tempDIR := t.TempDir()
+		files := []string{"main.tf", "auth0_import.tf", "generated.tf"}
+
+		for _, file := range files {
+			filePath := path.Join(tempDIR, file)
+			_, err := os.Create(filePath)
+			require.NoError(t, err)
+		}
+
+		stdout := &bytes.Buffer{}
+		cli := &cli{
+			renderer: &display.Renderer{
+				MessageWriter: stdout,
+				ResultWriter:  stdout,
+			},
+			force:   true,
+			noInput: true,
+		}
+
+		isEmpty := checkOutputDirectoryIsEmpty(cli, tempDIR)
+		assert.True(t, isEmpty)
+		assert.Contains(t, stdout.String(), "Proceeding will overwrite the main.tf, auth0_import.tf and generated.tf files.")
+	})
+}
+
+func TestCleanOutputDirectory(t *testing.T) {
+	t.Run("it can successfully clean the output directory from all generated files", func(t *testing.T) {
+		tempDIR := t.TempDir()
+		files := []string{"main.tf", "auth0_import.tf", "generated.tf"}
+
+		for _, file := range files {
+			filePath := path.Join(tempDIR, file)
+			_, err := os.Create(filePath)
+			require.NoError(t, err)
+		}
+
+		err := cleanOutputDirectory(tempDIR)
+		assert.NoError(t, err)
+
+		for _, file := range files {
+			filePath := path.Join(tempDIR, file)
+			_, err := os.Stat(filePath)
+			assert.ErrorContains(t, err, "no such file or directory")
+		}
+	})
+
+	t.Run("it returns an error if it can't remove a file", func(t *testing.T) {
+		files := []string{"main.tf", "auth0_import.tf", "generated.tf"}
+
+		for _, file := range files {
+			t.Run(file, func(t *testing.T) {
+				tempDIR := t.TempDir()
+
+				filePath := path.Join(tempDIR, file)
+				_, err := os.Create(filePath)
+				require.NoError(t, err)
+
+				err = os.Chmod(tempDIR, 0444)
+				require.NoError(t, err)
+
+				t.Cleanup(func() {
+					err = os.Chmod(tempDIR, 0755)
+					require.NoError(t, err)
+				})
+
+				err = cleanOutputDirectory(tempDIR)
+				assert.ErrorContains(t, err, "permission denied")
+			})
+		}
+	})
+}