AlistGo/alist · error

pattern must contain exactly one name token: {name}

Error message

pattern must contain exactly one name token: {name}

What it means

parseNameToken reports this when the chunk name format contains two or more {name} tokens. Exactly one is required: the driver builds a printf format string (%s for the name) and a regexp to reverse-match chunk files, and multiple name tokens are ambiguous.

Source

Thrown at drivers/chunker/util.go:129

	if chunkWidth > 0 {
		fmtDigits = fmt.Sprintf("%%0%dd", chunkWidth)
	}
	d.dataNameFmt = strings.ReplaceAll(beforeName, "%", "%%") +
		"%s" +
		strings.ReplaceAll(between, "%", "%%") +
		fmtDigits +
		strings.ReplaceAll(afterChunk, "%", "%%")
	return nil
}

func parseNameToken(pattern string) (start, end int, err error) {
	nameMagicCount := strings.Count(pattern, "{name}")
	switch nameMagicCount {
	case 0:
		return 0, 0, errors.New("pattern must contain one name token: {name}")
	case 1:
	default:
		return 0, 0, errors.New("pattern must contain exactly one name token: {name}")
	}
	start = strings.Index(pattern, "{name}")
	return start, start + len("{name}"), nil
}

func parseChunkToken(pattern string) (start, end, width int, err error) {
	chunkMatches := chunkTokenRegexp.FindAllStringSubmatchIndex(pattern, -1)
	switch len(chunkMatches) {
	case 0:
		return 0, 0, 0, errors.New("pattern must contain one chunk token: {chunk} or {chunk:N}")
	case 1:
	default:
		return 0, 0, 0, errors.New("pattern must contain exactly one chunk token: {chunk} or {chunk:N}")
	}
	match := chunkMatches[0]
	start = match[0]
	end = match[1]
	if match[2] >= 0 && match[3] >= 0 {

View on GitHub (pinned to 843d9dc814)

Solutions

1. Leave exactly one {name} token in the pattern
2. If you wanted name and extension split, note that {name} already denotes the full base name including extension — use it once

Example fix

// before
chunk_name_format: {name}.{name}_{chunk:03}
// after
chunk_name_format: {name}_{chunk:03}

if strings.Count(f, "{name}") != 1 {
    return fmt.Errorf("chunk name format must contain exactly one {name} token: %q", f)
}

When it happens

Trigger: A chunk_name_format like '{name}-{name}_{chunk:03}' or '{name}/{name}_{chunk}' (after removing separators). Raised in setChunkNameFormat at init time.

Common situations: Copy-paste concatenation of templates; attempting to simulate name+extension separately (e.g. '{name}.{name}'); editing an existing pattern and accidentally duplicating the token.

Related errors

• directory separator prohibited
• name token must come before chunk token
• pattern must contain one name token: {name}
• pattern must contain one chunk token: {chunk} or {chunk:N}
• pattern must contain exactly one chunk token: {chunk} or {ch

AI-assisted analysis of AlistGo/alist@843d9dc814 (2026-08-15). Data as JSON: /api/errors/97e921f82c6ab3cc. Report an issue: GitHub.