Package com.yahoo.search.grouping.vespa

Class GroupingExecutor

java.lang.Object
com.yahoo.component.AbstractComponent
com.yahoo.component.chain.ChainedComponent
com.yahoo.processing.Processor
com.yahoo.search.Searcher
com.yahoo.search.grouping.vespa.GroupingExecutor
All Implemented Interfaces:
com.yahoo.component.Component, com.yahoo.component.Deconstructable, Comparable<com.yahoo.component.Component>
public class GroupingExecutor extends Searcher
Executes the grouping requests set up by other searchers. This does the necessary transformation from the abstract request to Vespa grouping expressions (using RequestBuilder), and the corresponding transformation of results (using ResultBuilder).
Author:
Simon Thoresen Hult

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final String
    COMPONENT_NAME
     

    Fields inherited from class com.yahoo.component.AbstractComponent

    isDeconstructable

  • Constructor Summary

    Constructors
    Constructor
    Description
    GroupingExecutor(com.yahoo.component.ComponentId componentId)
    Constructs a new instance of this searcher with the given component id.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    fill(Result result, String summaryClass, Execution execution)
    Fill hit properties with data using the given summary class.
    static List<com.yahoo.searchlib.aggregation.Grouping>
    getGroupingList(Query query)
    Returns the list of Grouping objects assigned to the given query.
    static boolean
    hasGroupingList(Query query)
     
    Result
    search(Query query, Execution execution)
    Override this to implement your searcher.
    static void
    setGroupingList(Query query, List<com.yahoo.searchlib.aggregation.Grouping> list)
    Sets the list of Grouping objects assigned to the given query.

    Methods inherited from class com.yahoo.search.Searcher

    ensureFilled, getLogger, process, toString

    Methods inherited from class com.yahoo.component.chain.ChainedComponent

    getAnnotatedDependencies, getDefaultAnnotatedDependencies, getDependencies, initDependencies

    Methods inherited from class com.yahoo.component.AbstractComponent

    clone, compareTo, deconstruct, getClassName, getId, getIdString, hasInitializedId, initId, isDeconstructable, setIsDeconstructable

    Methods inherited from class java.lang.Object

    equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

  • Field Details

  • Constructor Details

    • GroupingExecutor

      public GroupingExecutor(com.yahoo.component.ComponentId componentId)
      Constructs a new instance of this searcher with the given component id.
      Parameters:
      componentId - the identifier to assign to this searcher

  • Method Details

    • search

      public Result search(Query query, Execution execution)
      Description copied from class: Searcher
      Override this to implement your searcher.

      Searcher implementation subclasses will, depending on their type of logic, do one of the following:

      • Query processors: Access the query, then call execution.search and return the result
      • Result processors: Call execution.search to get the result, access it and return
      • Sources (which produces results): Create a result, add the desired hits and return it.
      • Federators (which forwards the search to multiple subchains): Call search on the desired subchains in parallel and get the results. Combine the results to one and return it.
      • Workflows: Call execution.search as many times as desired, using different queries. Eventually return a result.

      Hits come in two kinds - concrete hits are actual content of the kind requested by the user, meta hits are hits which provides information about the collection of hits, on the query, the service and so on.

      The query specifies a window into a larger result list that must be returned from the searcher through hits and offset; Searchers which returns list of hits in the top level in the result must return at least hits number of hits (or if impossible; all that are available), starting at the given offset. In addition, searchers are allowed to return any number of meta hits (although this number is expected to be low). For hits contained in nested hit groups, the concept of a window defined by hits and offset is not well defined and does not apply.

      Error handling in searchers:

      • Unexpected events: Throw any RuntimeException. This query will fail with the exception message, and the error will be logged
      • Expected events: Create (new Result(Query, ErrorMessage) or add result.setErrorIfNoOtherErrors(ErrorMessage) an error message to the Result.
      • Recoverable user errors: Add a FeedbackHit explaining the condition and how to correct it.
      Specified by:
      search in class Searcher
      Parameters:
      query - the query
      Returns:
      the result of making this query

    • fill

      public void fill(Result result, String summaryClass, Execution execution)
      Description copied from class: Searcher
      Fill hit properties with data using the given summary class. Calling this on already filled results has no cost.

      This needs to be overridden by federating searchers to contact search sources again by propagating the fill call down through the search chain, and by source searchers which talks to fill capable backends to request the data to be filled. Other searchers do not need to override this.

      Overrides:
      fill in class Searcher
      Parameters:
      result - the result to fill
      summaryClass - the name of the collection of fields to fetch the values of, or null to use the default

    • getGroupingList

      public static List<com.yahoo.searchlib.aggregation.Grouping> getGroupingList(Query query)
      Returns the list of Grouping objects assigned to the given query. If no list has been assigned, this method returns an empty list.
      Parameters:
      query - the query whose grouping list to return
      Returns:
      the list of assigned grouping objects

    • hasGroupingList

      public static boolean hasGroupingList(Query query)

    • setGroupingList

      public static void setGroupingList(Query query, List<com.yahoo.searchlib.aggregation.Grouping> list)
      Sets the list of Grouping objects assigned to the given query. This method overwrites any grouping objects already assigned to the query.
      Parameters:
      query - the query whose grouping list to set
      list - the grouping list to set