io.lettuce.core.search

Class AggregationReply<K,V>

java.lang.Object

io.lettuce.core.search.AggregationReply<K,V>

Type Parameters:

K - the type of keys used in the aggregation results

V - the type of values used in the aggregation results

public class AggregationReply<K,V>
extends Object

Represents the response from a Redis Search aggregation command (FT.AGGREGATE) or an (FT.CURSOR READ) command. This class encapsulates the results of aggregation operations including grouped data, statistical computations, and cursor-based pagination for large result sets.

An aggregation reply contains:

• The number of aggregation groups returned
• A list of SearchReply objects, each representing an aggregation group or result set
• An optional cursor ID for pagination when dealing with large aggregation results

Aggregation operations can include:

• Grouping by one or more fields
• Statistical functions (COUNT, SUM, AVG, MIN, MAX, etc.)
• Sorting and limiting results
• Filtering and transformations

For cursor-based pagination, when the result set is too large to return in a single response, Redis returns a cursor ID that can be used with FT.CURSOR READ to retrieve subsequent pages.

Since:

6.8

Author:

Redis Ltd.

See Also:

SearchReply

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AggregationReply.Cursor Lightweight cursor handle containing the server-assigned cursor id and optional node id (cluster sticky routing).

Constructor Summary

Constructors

Constructor and Description
AggregationReply() Creates a new empty AggregationReply.

Method Summary

Modifier and Type	Method and Description
long	getAggregationGroups() Returns the number of aggregation groups in this reply.
Optional<AggregationReply.Cursor>	getCursor() Returns the optional Cursor metadata for pagination and (in cluster) sticky routing, if applicable.
List<SearchReply<K,V>>	getReplies() Returns the list of search replies containing the aggregation results.
void	setCursor(AggregationReply.Cursor cursor) Set the AggregationReply.Cursor metadata carried by this reply.

Methods inherited from class java.lang.Object

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

Constructor Detail

AggregationReply

public AggregationReply()

Creates a new empty AggregationReply. The reply is initialized with defaults.

Method Detail

getAggregationGroups

public long getAggregationGroups()

Returns the number of aggregation groups in this reply.

This value represents:

• For grouped aggregations: the number of distinct groups returned
• For non-grouped aggregations: typically 1, representing the entire result set
• For empty results: may be 0 or 1 depending on the aggregation type

Note: This count may be different from getReplies().size() in some cases, particularly when dealing with cursor-based pagination where not all groups are returned in a single response.

Returns:

the number of aggregation groups, typically a positive integer

getReplies

public List<SearchReply<K,V>> getReplies()

Returns the list of search replies containing the aggregation results.

Each SearchReply in the list represents:

• For grouped aggregations: one aggregation group with its computed values
• For non-grouped aggregations: typically a single reply containing all results
• For cursor-based results: the current page of results

The structure of each SearchReply depends on the aggregation operations performed:

• GROUP BY operations create separate replies for each group
• REDUCE operations add computed fields to each reply
• LOAD operations include specified fields in the results
• SORTBY operations determine the order of replies

The returned list is mutable and reflects the current state of the aggregation results. Modifying this list will affect the aggregation reply.

Returns:

a mutable list of SearchReply objects containing the aggregation results. Never null, but may be empty if no results were found.

getCursor

public Optional<AggregationReply.Cursor> getCursor()

Returns the optional Cursor metadata for pagination and (in cluster) sticky routing, if applicable.

When WITHCURSOR is used and Redis returns a cursor, this method yields a AggregationReply.Cursor containing the cursor id. In cluster mode, the cursor may additionally carry the node id on which the cursor resides for sticky FT.CURSOR READ/DEL routing.

Returns:

an Optional with AggregationReply.Cursor when a cursor was returned; otherwise an empty Optional.

setCursor

public void setCursor(AggregationReply.Cursor cursor)

Set the AggregationReply.Cursor metadata carried by this reply. Intended for post-parse stamping of node affinity (cluster mode) or attaching the server-returned cursor id (standalone).