RedisConversationHistoryStore

This docs was updated at: 2026-02-23

com.paragon.messaging.store.history.RedisConversationHistoryStore  ·  Class

Implements ConversationHistoryStore

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Redis-backed implementation of ConversationHistoryStore.

Provides persistent conversation history storage using Redis sorted sets. Each user's history is stored in a separate sorted set with message timestamps as scores for efficient time-based queries.

Redis Data Structure

• Key: {keyPrefix:history:{userId}}
• Type: Sorted Set (ZSET)
• Score: Message timestamp (epoch milliseconds)
• Value: JSON-serialized message

Features

• Persistent storage across application restarts
• Automatic TTL-based expiration
• Efficient time-range queries using sorted set scores
• Configurable key prefix for multi-tenant deployments
• Thread-safe (Redis operations are atomic)

Usage Example

// Using Lettuce Redis client (included in Spring Data Redis)
RedisClient redisClient = RedisClient.create("redis://localhost:6379");
StatefulRedisConnection connection = redisClient.connect();
RedisCommands commands = connection.sync();
// Create store with Lettuce commands wrapper
RedisConversationHistoryStore store = RedisConversationHistoryStore.builder()
    .redisOperations(new LettuceRedisOperations(commands))
    .keyPrefix("whatsapp")
    .defaultTtl(Duration.ofDays(7))
    .maxMessagesPerUser(100)
    .build();
// Or use Spring Data Redis
RedisConversationHistoryStore store = RedisConversationHistoryStore.builder()
    .redisOperations(new SpringDataRedisOperations(stringRedisTemplate))
    .build();

Dependencies

This class requires a Redis client. Supported options: - Lettuce (recommended, included in Spring Boot) - Spring Data Redis (RedisTemplate) - Jedis

See Also

• ConversationHistoryStore
• RedisOperations

Since: 2.1

Methods

builder

public static Builder builder()

Creates a builder for customizing the Redis store.

Returns

a new builder

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zadd

void zadd(String key, double score, String member)

Adds a member to a sorted set with the given score.

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zcard

long zcard(String key)

Gets the number of members in a sorted set.

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zrangeByScore

List<String> zrangeByScore(String key, double min, double max)

Gets members within a score range, ordered by score ascending.

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zremrangeByScore

long zremrangeByScore(String key, double min, double max)

Removes members with scores in the given range.

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zremrangeByRank

long zremrangeByRank(String key, long start, long stop)

Removes members by rank range.

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expire

void expire(String key, Duration ttl)

Sets the expiration time for a key.

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del

void del(String... keys)

Deletes one or more keys.

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keys

Set<String> keys(String pattern)

Finds all keys matching the given pattern.

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redisOperations

public Builder redisOperations(@NonNull RedisOperations operations)

Sets the Redis operations implementation.

This is required. Implement RedisOperations to adapt your preferred Redis client.

Parameters

Name	Description
operations	the Redis operations

Returns

this builder

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objectMapper

public Builder objectMapper(@Nullable ObjectMapper objectMapper)

Sets the ObjectMapper for JSON serialization.

If not set, a default ObjectMapper with Message type handling will be created.

Parameters

Name	Description
objectMapper	the object mapper

Returns

this builder

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keyPrefix

public Builder keyPrefix(@NonNull String prefix)

Sets the key prefix for Redis keys.

Default is "conversation". Keys will be formatted as: {prefix:history:{userId}}

Parameters

Name	Description
prefix	the key prefix

Returns

this builder

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defaultTtl

public Builder defaultTtl(@NonNull Duration ttl)

Sets the default TTL for conversation history.

Default is 7 days. This TTL is refreshed each time a message is added to a user's history.

Parameters

Name	Description
ttl	the time-to-live duration

Returns

this builder

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maxMessagesPerUser

public Builder maxMessagesPerUser(int max)

Sets the maximum messages to store per user.

Default is 100. When exceeded, oldest messages are removed.

Parameters

Name	Description
max	the maximum messages per user

Returns

this builder

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build

public RedisConversationHistoryStore build()

Builds the configured RedisConversationHistoryStore.

Returns

the store instance

Throws

Type	Condition
IllegalStateException	if redisOperations is not set