Allow json output

Signed-off-by: Bryan Frimin <bryan@probo.com>

cmd/probod-bootstrap/main.go

@@ -29,6 +29,7 @@ var (
 
 func main() {
 	outputPath := flag.String("output", "/etc/probod/config.yml", "output path for the generated config file")
+	format := flag.String("format", "yaml", "output format for the generated config file (yaml or json)")
 	showVersion := flag.Bool("version", false, "print version and exit")
 
 	flag.Parse()
@@ -38,6 +39,17 @@ func main() {
 		return
 	}
 
+	var configFormat bootstrap.Format
+	switch *format {
+	case "yaml":
+		configFormat = bootstrap.FormatYAML
+	case "json":
+		configFormat = bootstrap.FormatJSON
+	default:
+		fmt.Fprintf(os.Stderr, "error: unsupported format %q, must be yaml or json\n", *format)
+		os.Exit(1)
+	}
+
 	builder := bootstrap.NewBuilder(bootstrap.NewResolver(nil))
 
 	cfg, err := builder.Build()
@@ -46,7 +58,7 @@ func main() {
 		os.Exit(1)
 	}
 
-	if err := bootstrap.WriteConfig(cfg, *outputPath); err != nil {
+	if err := bootstrap.WriteConfig(cfg, *outputPath, configFormat); err != nil {
 		fmt.Fprintf(os.Stderr, "error: %v\n", err)
 		os.Exit(1)
 	}