can now print output to stdout using: -o stdout

cmd/build.go

@@ -13,8 +13,8 @@
 type BuildCmd struct {
 	Args struct {
 		DryRun bool   `short:"d" long:"dry-run" description:"if set only prints commands but do not run them"`
-		Keep   bool   `short:"k" long:"keep" descriptions:"Keep the temporary files"`
-		Output string `short:"o" long:"output" descriptions:"output directory"`
+		Keep   bool   `short:"k" long:"keep" description:"Keep the temporary files"`
+		Output string `short:"o" long:"output" description:"output directory, use \"stdout\" to print to stdout"`
 	}
 	PositionalArgs struct {
 		DirName string `required:"yes" positional-arg-name:"directory"`

runner/main.go

@@ -54,11 +54,13 @@
 	if err != nil {
 		return fmt.Errorf("cannot list directory: %s - %w", preBuildDir, err)
 	}
-	if err := CleanDir(outputDir); err != nil {
-		return fmt.Errorf("cannot clean dir: %s: %w", outputDir, err)
+	if outputDir != "stdout" {
+		if err := CleanDir(outputDir); err != nil {
+			return fmt.Errorf("cannot clean dir: %s: %w", outputDir, err)
+		}
 	}
 	variables, err := r.config.prepareVariables(true)
 	if err != nil {
 		return fmt.Errorf("cannot prepare variables: %w", err)
 	}
 	for _, file := range files {
@@ -59,7 +61,9 @@
 	}
 	variables, err := r.config.prepareVariables(true)
 	if err != nil {
 		return fmt.Errorf("cannot prepare variables: %w", err)
 	}
 	for _, file := range files {
+		var outFilePath string
+		var outFile *os.File
 		inFilePath := filepath.Join(preBuildDir, file.Name())
@@ -65,6 +69,16 @@
 		inFilePath := filepath.Join(preBuildDir, file.Name())
-		outFilePath := filepath.Join(outputDir, file.Name())
-		outFile, err := os.Create(outFilePath)
-		if err != nil {
-			return fmt.Errorf("cannot open: %s - %w", outFilePath, err)
+		if outputDir == "stdout" {
+			outFilePath = "stdout"
+			outFile = os.Stdout
+		} else {
+			outFilePath = filepath.Join(outputDir, file.Name())
+			outFile, err = os.Create(outFilePath)
+			if err != nil {
+				return fmt.Errorf("cannot open: %s - %w", outFilePath, err)
+			}
+			defer func() {
+				if err := outFile.Close(); err != nil {
+					r.config.Logger.Fatal().Err(err).Msg("cannot close hydrated file")
+				}
+			}()
 		}
@@ -70,9 +84,4 @@
 		}
-		defer func() {
-			if err := outFile.Close(); err != nil {
-				r.config.Logger.Fatal().Err(err).Msg("cannot close hydrated file")
-			}
-		}()
 		if err := hydrate(inFilePath, outFile, variables); err != nil {
 			return fmt.Errorf("cannot hydrate: %s - %w", outFilePath, err)
 		}