[ https://issues.apache.org/jira/browse/KAFKA-3104?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Work on KAFKA-3104 started by Guozhang Wang. -------------------------------------------- > Windowed Stream Aggregation Implementation > ------------------------------------------ > > Key: KAFKA-3104 > URL: https://issues.apache.org/jira/browse/KAFKA-3104 > Project: Kafka > Issue Type: Sub-task > Reporter: Guozhang Wang > Assignee: Guozhang Wang > > Proposed approach: > 1. Add a K-V store with format <key, window> : <agg-value> with Windowed<K> > ser-de and <T> ser-de. > 2. Upon receiving a record forwarded from the upstream processor: > 2.1. First get the mapping window(s) from the context timestamp. > 2.2. For each window, first try fetch from the store, if not exist call > initialValue(). > 2.2. Only call add(..), and never call remove(..) > 2.3. Forward the aggregate value with key Windowed<agg-key> and value > Change<agg-value>. -- This message was sent by Atlassian JIRA (v6.3.4#6332)