Add initial distributor CLI skeleton

internal/cli/validate.go

@@ -0,0 +1,36 @@
+package cli
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"gitea.maximumdirect.net/eric/distributor/internal/app"
+)
+
+func validateCommand(ctx context.Context, args []string, stdout, stderr io.Writer) int {
+	if hasHelp(args) {
+		printValidateHelp(stdout)
+		return exitOK
+	}
+	if len(args) > 1 {
+		fmt.Fprintf(stderr, "%s: validate accepts at most one path\n", app.Name)
+		return exitUsage
+	}
+	var path string
+	if len(args) == 1 {
+		path = args[0]
+	}
+	if err := app.Validate(ctx, app.ValidateOptions{Path: path}); err != nil {
+		return fail(stderr, err)
+	}
+	return exitOK
+}
+
+func printValidateHelp(w io.Writer) {
+	fmt.Fprint(w, `Usage:
+  distributor validate <path>
+
+The validate command is present but bundle validation is not implemented yet.
+`)
+}