ACK Command

Syntax

ACK;CLIENT_ID=client_id;EVENT_IDEM=unique_id;EVENT_NAME=event_type;PARTITION_BLOCK=block_number

Parameter	Description	Required	Example
CLIENT_ID	ID of the client acknowledging the event	Yes	`client-123abc`
EVENT_IDEM	Unique ID of the event to acknowledge	Yes	`evt_12345abcde`
EVENT_NAME	Type of event being acknowledged	Yes	`user/profile/updated`
PARTITION_BLOCK	Partition block of the event	Yes	`19345`

+PASS:ACKNOWLEDGED;IDEM=evt_12345abcde

The response includes the ID of the acknowledged event.

-FAIL:MISSING_PARAMETERS;MESSAGE=Missing required acknowledgment data. Ensure CLIENT_ID, EVENT_IDEM, EVENT_NAME, and PARTITION_BLOCK are passed

-FAIL:NOT_FOUND;MESSAGE=Event not found in processing queue

-FAIL:UNAUTHORIZED;MESSAGE=Client is not authorized to acknowledge this event

ACK;CLIENT_ID=client-123abc;EVENT_IDEM=evt_12345abcde;EVENT_NAME=user/profile/updated;PARTITION_BLOCK=19345

The ACK command confirms successful processing of an event
Acknowledged events are removed from the client's processing queue
The client's position in the event stream is updated in persistent storage
Acknowledgment may trigger queue refill operations when thresholds are reached
The system implements a two-phase acknowledgment process:
1. First mark the event as acknowledged in Valkey (Redis)
2. Then update the client position in the database
Only the client that is currently processing an event can acknowledge it
The PARTITION_BLOCK parameter is used for efficient database queries when updating client position

Last modified: 07 October 2025