Add JSON output format for CLI commands

internal/cli/validate.go

@@ -2,6 +2,7 @@ package cli
 
 import (
 	"context"
+	"flag"
 	"fmt"
 	"io"
 
@@ -13,11 +14,21 @@ func validateCommand(ctx context.Context, args []string, stdout, stderr io.Write
 		printValidateHelp(stdout)
 		return exitOK
 	}
-	path, ok := parseOptionalPathArg(stderr, "validate", args)
+	flags := flag.NewFlagSet("validate", flag.ContinueOnError)
+	flags.SetOutput(stderr)
+	formatFlag := addFormatFlag(flags)
+	if err := flags.Parse(args); err != nil {
+		return exitUsage
+	}
+	format, ok := parseOutputFormat(stderr, "validate", *formatFlag)
 	if !ok {
 		return exitUsage
 	}
-	if err := app.Validate(ctx, app.ValidateOptions{Path: path, Stdout: stdout}); err != nil {
+	path, ok := parseOptionalPathArg(stderr, "validate", flags.Args())
+	if !ok {
+		return exitUsage
+	}
+	if err := app.Validate(ctx, app.ValidateOptions{Path: path, Stdout: stdout, OutputFormat: format}); err != nil {
 		return fail(stderr, err)
 	}
 	return exitOK
@@ -25,7 +36,10 @@ func validateCommand(ctx context.Context, args []string, stdout, stderr io.Write
 
 func printValidateHelp(w io.Writer) {
 	fmt.Fprint(w, `Usage:
-  distributor validate <path>
+  distributor validate [--format text|json] <path>
+
+Options:
+  --format text|json  Output format
 
 Validate a local source bundle directory or a tree containing source bundles.
 `)