Status

Current state: Discarded (we don't need a KIP for this change)

Discussion thread: here

JIRA: here

Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).

Motivation

KIP-358 introduced typed representation for Window Store Interactive Query API (ReadOnlyWindowStore) to improve usability.

On the other hand, Processor API read-write Store APIs are tuned for automation, therefore they should keep the long-based methods to represent time ranges to avoid object allocation.

Deprecation notes for long-based read operations in ReadOnlyWindowStore were added in 2.1.0.

Based on these, this proposal includes:

• Remove deprecated methods from ReadOnlyWindowStore
  
• Remove deprecation annotation on long-based read operations in WindowStore

All these changes are targeting the next major release. Currently v3.0.

Similar changes for SessionStore are considered in KIP-666, but can be introduced earlier as they do not include removing deprecated methods.

Public Interfaces

• org.apache.kafka.streams.state.ReadOnlyWindowStore
  • Remove method: WindowStoreIterator<V> fetch(K key, long timeFrom, long timeTo)
  • Remove method: KeyValueIterator<Windowed<K>, V> fetch(K from, K to, long timeFrom, long timeTo)
  • Remove method: KeyValueIterator<Windowed<K>, V> fetchAll(long timeFrom, long timeTo)
• org.apache.kafka.streams.state.WindowStore
  • Remove @Deprecated annotation: WindowStoreIterator<V> fetch(K key, long timeFrom, long timeTo)
  • Remove @Deprecated annotation: KeyValueIterator<Windowed<K>, V> fetch(K from, K to, long timeFrom, long timeTo)
  • Remove @Deprecated annotation: KeyValueIterator<Windowed<K>, V> fetchAll(long timeFrom, long timeTo)

Compatibility, Deprecation, and Migration Plan

• Users implementing custom stores or interactive query API for WindowStore will have to remove long-based methods and migrate to Instant-based ones. This is why this KIP is targeting v3.0

Rejected Alternatives

None.