1Panel-dev/1Panel · error

unexpected end of file while scanning a string, maybe an unc

Error message

unexpected end of file while scanning a string, maybe an unclosed lua code?

What it means

Panic in the nginx-config lexer's scanLuaCode when EOF is hit while scanning a *_by_lua_block { ... } region — brace nesting tracked on a rune stack never closed, so the scanner ran off the end of the input. It is a hard parse error for unbalanced lua blocks.

Source

Thrown at agent/utils/nginx/parser/lexer.go:91

		return s.scanComment()
	case ch == '$':
		return s.scanVariable()
	case isQuote(ch):
		return s.scanQuotedString(ch)
	default:
		return s.scanKeyword()
	}
}

func (s *lexer) scanLuaCode() flag.Flag {
	ret := s.NewToken(flag.LuaCode)
	stack := make([]rune, 0, 50)
	code := strings.Builder{}

	for {
		ch := s.read()
		if ch == rune(flag.EOF) {
			panic("unexpected end of file while scanning a string, maybe an unclosed lua code?")
		}
		if ch == '#' {
			code.WriteRune(ch)
			code.WriteString(s.readUntil(isEndOfLine))
			continue
		} else if ch == '}' {
			if len(stack) == 0 {
				_ = s.reader.UnreadRune()
				return ret.Lit(strings.TrimRight(strings.Trim(code.String(), "\n"), "\n  "))
			}
			if stack[len(stack)-1] == '{' {
				stack = stack[0 : len(stack)-1]
			}
		} else if ch == '{' {
			stack = append(stack, ch)
		}
		code.WriteRune(ch)
	}

View on GitHub (pinned to 5ac7c80881)

Solutions

1. Open the file reported by the parse operation and balance the braces in the *_by_lua_block section (count { vs })
2. Validate before saving: nginx -t -c <file> or re-parse via the same agent parser in a test
3. Restore the previous config version from 1Panel's config history if the edit broke it

Example fix

# before
access_by_lua_block {
  if x then
    do_thing()
# after
access_by_lua_block {
  if x then
    do_thing()
  end
}

python3 - <<'PY'
import sys
txt = open(sys.argv[1]).read()
assert txt.count('{') == txt.count('}'), f"unbalanced braces: {{={txt.count('{')} }}={txt.count('}')}"
print('braces balanced')
PY /opt/1panel/apps/openresty/openresty/conf/nginx.conf

When it happens

Trigger: A config contains access_by_lua_block { ... with a missing closing '}' (or nested unbalanced braces inside the lua code), and the agent parses that file with agent/utils/nginx/parser.

Common situations: Hand-written WAF/rate-limit lua snippets with an extra '{' or a deleted '}'; truncated config after an interrupted save; copy-paste that dropped the last line.

Related errors

• unexpected end of file while scanning a string, maybe an unc
• no enough parameter for location
• unexpected token %s (%s) on line %d, column %d
• Fatal error config file: %s \n
• init db dir failed, err: %v

AI-assisted analysis of 1Panel-dev/1Panel@5ac7c80881 (2026-08-15). Data as JSON: /api/errors/c074c84f6711d17d. Report an issue: GitHub.