elastic/elasticsearch

Add a checkCancelled public method to ContextIndexSearcher

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#121 349 ouverte le 30 janv. 2025

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 (5 commentaires) (0 réactions) (0 assignés)Java (76 700 stars) (25 882 forks)batch import
:Search Foundations/Search>enhancementTeam:Search Foundationshelp wanted

Description

Description

The ContextIndexSearcher has some API to deal with cancelled tasks, see for example hasCancellations() below. Acting on cancelled tasks can be useful in ValueFetchers (which can be implemented by plugins via custom runtime fields), where resources can be released in such a case. Although the method hasCancellations() is public and accessible to plugins, there is however no access point to its counterpart checkCancelled() (see below): that method would be needed to check if the search's task got cancelled (and act upon it).

  • Would it be possible to add a public access method to checkCancelled(), in order to allow plugins to handle cancellations in custom runtime fields ?
  • Related question: are IndexSearchers used in Elasticsearch all ContextIndexSearcher instances ?

https://github.com/elastic/elasticsearch/blob/0d2db063ec4d8e95941e3b92dc150e294e5f0689/server/src/main/java/org/elasticsearch/search/internal/ContextIndexSearcher.java#L193

https://github.com/elastic/elasticsearch/blob/0d2db063ec4d8e95941e3b92dc150e294e5f0689/server/src/main/java/org/elasticsearch/index/mapper/MappedFieldType.java#L118

https://github.com/elastic/elasticsearch/blob/0d2db063ec4d8e95941e3b92dc150e294e5f0689/server/src/main/java/org/elasticsearch/search/internal/ContextIndexSearcher.java#L594

Guide contributeur

Stack technique
java
Domaine
backend
Type d'issue
feature
DifficultéDifficulté estimée pour un nouveau contributeur, de 1 pour un très petit changement à 5 pour un travail expert.
3
Temps estiméFourchette de temps approximative pour investiguer, implémenter, tester et préparer une pull request.
1-3 hours
Statut d'activitéDisponibilité apparente de l'issue : fraîche, active, ancienne, bloquée ou en attente d'un mainteneur.
fresh
ClartéClarté avec laquelle l'issue explique le changement attendu, les critères d'acceptation et la prochaine étape.
clear
Prérequis
JavaElasticsearch search internals
Accessibilité débutantScore de 1 à 100 estimant l'accessibilité de cette issue pour un premier contributeur.
60
Direction de recherche
Examine ContextIndexSearcher.java (lines 193 and 594) to understand the existing private checkCancelled method and its relationship to hasCancellations. Check the linked MappedFieldType.java to understand how ValueFetchers use cancellation. Review comments in the issue #121349 for maintainer feedback on whether all IndexSearcher instances are ContextIndexSearcher, and whether a public method is acceptable. The change may involve adding a simple public wrapper that delegates to the private checkCancelled, following existing patterns.