gohugoio/hugo · error

index config for %q not found

Error message

index config for %q not found

What it means

Returned by InvertedIndex.searchDate as a defensive check when getIndexCfg cannot find the IndexConfig for a query element's index name. Because searchDate is only called after Search resolves configs, reaching this branch indicates the config and the constructed index are out of sync -- the posting-list map has the index (527 passed) but the config slice does not.

Source

Thrown at related/inverted_index.go:479

	matchm := make(map[Document]*rank, 200)
	defer func() {
		for _, r := range matchm {
			putRank(r)
		}
	}()

	applyDateFilter := !idx.cfg.IncludeNewer && !upperDate.IsZero()
	var fragmentsFilter collections.SortedStringSlice

	for _, el := range query {
		setm, found := idx.index[el.Index]
		if !found {
			return []Document{}, fmt.Errorf("index for %q not found", el.Index)
		}

		config, found := idx.getIndexCfg(el.Index)
		if !found {
			return []Document{}, fmt.Errorf("index config for %q not found", el.Index)
		}

		for _, kw := range el.Keywords {
			if docs, found := setm[kw]; found {
				for _, doc := range docs {
					if compare.Eq(doc, self) {
						continue
					}

					if applyDateFilter {
						// Exclude newer than the limit given
						if doc.PublishDate().After(upperDate) {
							continue
						}
					}

					if config.Type == TypeFragments && config.ApplyFilter {
						if fkw, ok := kw.(FragmentKeyword); ok {

View on GitHub (pinned to 52c9bd7908)

Solutions

1. Treat the related Config as immutable after NewInvertedIndex; rebuild the index if config changes.
2. Ensure NewInvertedIndex receives the fully-decoded, final Config.
3. Avoid sharing a Config value between index construction and later mutation.

Example fix

// before: mutate cfg after building index
cfg.Indices = append(cfg.Indices, newIndex)
idx := related.NewInvertedIndex(cfg)
cfg.Indices = cfg.Indices[:0]  // desync!

// after: build once, never mutate
finalCfg := buildRelatedConfig()
idx := related.NewInvertedIndex(finalCfg)

// Treat Config as immutable; rebuild index on change.
func rebuildIndex(cfg related.Config) *related.InvertedIndex {
    return related.NewInvertedIndex(cfg) // cfg must be final, never mutated after
}

When it happens

Trigger: An index name exists as a key in idx.index (added at construction time) but idx.cfg.Indices no longer contains an IndexConfig with that Name -- e.g. config mutated after NewInvertedIndex, or a partial config reload.

Common situations: Runtime mutation of the related Config after the InvertedIndex was built; a custom integration that partially rebuilds config; concurrent config swap without recreating the index.

Related errors

• index for %q not found
• failed to decode related config: %w
• index %q not found
• index %q not valid
• there is no such an operation

AI-assisted analysis of gohugoio/hugo@52c9bd7908 (2026-08-09). Data as JSON: /api/errors/0b935245b1f949b3. Report an issue: GitHub.