snapshot of https://github.com/blevesearch/bleve.git (master, 2026-09-15; blobs > 131072B omitted)

search/term_limit.go

@@ -0,0 +1,63 @@
+//  Copyright (c) 2026 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package search
+
+import (
+	"context"
+	"fmt"
+	"sync/atomic"
+)
+
+// termSearchersCounter tracks the running total of leaf term searchers created
+// while searching a single index and the limit beyond which construction fails.
+type termSearchersCounter struct {
+	limit int
+	count atomic.Uint64
+}
+
+// ContextWithTermSearchersCounter installs a fresh counter for the limit at
+// MaxTermSearchersKey, when that limit is positive. It is called once per index
+// search (indexImpl.SearchInContext), so the counter is scoped to that index:
+// within a single index it spans the whole query tree (all fan-out nodes share
+// one counter), but across an IndexAlias each index is counted independently.
+// context is returned unchanged and RecordTermSearcher stays a no-op.
+func ContextWithTermSearchersCounter(ctx context.Context) context.Context {
+	if ctx == nil {
+		return ctx
+	}
+	limit, ok := ctx.Value(MaxTermSearchersKey).(int)
+	if !ok || limit <= 0 {
+		return ctx
+	}
+	return context.WithValue(ctx, termSearchersCounterKey,
+		&termSearchersCounter{limit: limit})
+}
+
+// RecordTermSearcher counts one leaf term searcher, returning an error once the
+// running total exceeds the limit. It is a no-op when no counter was installed.
+func RecordTermSearcher(ctx context.Context) error {
+	if ctx == nil {
+		return nil
+	}
+	c, ok := ctx.Value(termSearchersCounterKey).(*termSearchersCounter)
+	if !ok || c == nil {
+		return nil
+	}
+	if n := c.count.Add(1); n > uint64(c.limit) {
+		return fmt.Errorf("TooManyTermSearchers [%d > bleveMaxTerms,"+
+			" which is set to %d]", n, c.limit)
+	}
+	return nil
+}