Package com.tnsai.idempotency

Class RedisIdempotencyStore

java.lang.Object

com.tnsai.idempotency.RedisIdempotencyStore

All Implemented Interfaces:

IdempotencyStore

public final class RedisIdempotencyStore
extends Object
implements IdempotencyStore

Distributed IdempotencyStore backed by Redis (issue #91). Use this when the framework runs as more than one process and dedup needs to survive a crash or a horizontal restart.

Commands use the caller-owned, pooled RedisClient, so the store can be shared across threads. The caller closes the client at application shutdown; store operations never close it. TTL is enforced server-side via SET ... EX ..., so stale entries need no sweep.

Entries are JSON-encoded by IdempotencyEntryCodec. The round-trip is generic-JSON (not type-preserving): a typed POJO cached in process A and read in process B comes back as a Map/List mosaic. Consumers needing the original type should re-marshal at the call site.

Optional dependency

Jedis is declared as an <optional> dependency on tnsai-core: consumers add it themselves to opt in. Loading this class without Jedis on the classpath is a hard NoClassDefFoundError -- by design, since the store cannot function without it.

Key prefix

The configured prefix is prepended to every key the store touches, giving operators a way to share a Redis instance across multiple unrelated TnsAI deployments. Default "tnsai:idem:" is safe for sole-tenant Redis but should be customised for shared clusters.

Since:

0.10.0 (issue #91 closeout)

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DEFAULT_KEY_PREFIX	Default key prefix; safe for sole-tenant Redis.

Constructor Summary

Constructors

Constructor	Description
RedisIdempotencyStore(redis.clients.jedis.RedisClient client)	Uses DEFAULT_KEY_PREFIX with a caller-owned client; the store never closes it.
RedisIdempotencyStore(redis.clients.jedis.RedisClient client, String keyPrefix)	Uses a caller-owned client; the store never closes it.

Method Summary

Modifier and Type	Method	Description
Optional<IdempotencyEntry>	get(String key)	Look up a cached entry.
void	invalidate(String key)	Remove the entry for key if any.
void	put(String key, IdempotencyEntry entry, Duration ttl)	Store an entry under key with the given TTL.
int	size()	Approximate entry count.

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_KEY_PREFIX

public static final String DEFAULT_KEY_PREFIX

Default key prefix; safe for sole-tenant Redis.

See Also:

• Constant Field Values

Constructor Details

RedisIdempotencyStore

public RedisIdempotencyStore(redis.clients.jedis.RedisClient client)

Uses DEFAULT_KEY_PREFIX with a caller-owned client; the store never closes it.

Since:

0.17.5

RedisIdempotencyStore

public RedisIdempotencyStore(redis.clients.jedis.RedisClient client,
 String keyPrefix)

Uses a caller-owned client; the store never closes it.

Since:

0.17.5

Method Details

get

public Optional<IdempotencyEntry> get(String key)

Description copied from interface: IdempotencyStore

Look up a cached entry. Returns empty when no entry exists OR when the entry's TTL has elapsed.

Specified by:

get in interface IdempotencyStore

put

public void put(String key,
 IdempotencyEntry entry,
 Duration ttl)

Description copied from interface: IdempotencyStore

Store an entry under key with the given TTL. Subsequent IdempotencyStore.get(java.lang.String) calls within the TTL window return this entry. Overwrites any prior entry for the same key.

Specified by:

put in interface IdempotencyStore

invalidate

public void invalidate(String key)

Description copied from interface: IdempotencyStore

Remove the entry for key if any. No-op if the key is not present.

Specified by:

invalidate in interface IdempotencyStore

size

public int size()

Description copied from interface: IdempotencyStore

Approximate entry count. Intended for monitoring / smoke-testing ("cache has grown to 10M entries, check your TTL"). Implementations may return an eventually-consistent snapshot.

Specified by:

size in interface IdempotencyStore