From def3e886511e4cbac53e5f78525d481b36ba91c0 Mon Sep 17 00:00:00 2001
From: James Hillyerd <james@hillyerd.com>
Date: Fri, 16 Feb 2024 14:16:17 -0800
Subject: [PATCH] luahost: use sentinel ErrNoScript (#490)

Signed-off-by: James Hillyerd <james@hillyerd.com>
---
 pkg/extension/luahost/lua.go | 6 +++++-
 pkg/server/lifecycle.go      | 2 +-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/pkg/extension/luahost/lua.go b/pkg/extension/luahost/lua.go
index 45788b9..dd07cfd 100644
--- a/pkg/extension/luahost/lua.go
+++ b/pkg/extension/luahost/lua.go
@@ -2,6 +2,7 @@ package luahost
 
 import (
 	"bufio"
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -15,6 +16,9 @@ import (
 	"github.com/yuin/gopher-lua/parse"
 )
 
+// ErrNoScript signals that the Lua script file was not present.
+var ErrNoScript error = errors.New("no script file present")
+
 // Host of Lua extensions.
 type Host struct {
 	extHost    *extension.Host
@@ -35,7 +39,7 @@ func New(conf config.Lua, extHost *extension.Host) (*Host, error) {
 	// Pre-load, parse, and compile script.
 	if fi, err := os.Stat(scriptPath); err != nil {
 		logger.Info().Msg("Script file not found")
-		return nil, nil
+		return nil, ErrNoScript
 	} else if fi.IsDir() {
 		return nil, fmt.Errorf("lua script %v is a directory", scriptPath)
 	}
diff --git a/pkg/server/lifecycle.go b/pkg/server/lifecycle.go
index 1f68748..a770e99 100644
--- a/pkg/server/lifecycle.go
+++ b/pkg/server/lifecycle.go
@@ -37,7 +37,7 @@ func FullAssembly(conf *config.Root) (*Services, error) {
 	// Configure extensions.
 	extHost := extension.NewHost()
 	luaHost, err := luahost.New(conf.Lua, extHost)
-	if err != nil {
+	if err != nil && err != luahost.ErrNoScript {
 		return nil, err
 	}