DISCARD Command Overview
Purpose
The DISCARD command provides a critical safety mechanism in the EnSync event processing system, allowing clients to permanently remove events from the processing pipeline. This command is essential for handling duplicate events, invalid data, and other scenarios where an event should not be processed.
Key Capabilities
Permanent Event Removal
Unlike the DEFER command which postpones processing, DISCARD permanently removes an event from the system. This capability is crucial for handling events that should never be processed, such as duplicates or events with invalid data.
Audit Trail
The DISCARD command requires a reason parameter, ensuring that all discarded events are properly documented. This audit trail is essential for debugging, compliance, and understanding system behavior.
Error Handling
By providing a clean way to handle invalid events, DISCARD enables robust error handling strategies. Services can identify problematic events and remove them from the system without disrupting the processing of valid events.
Resource Optimization
Removing events that should not be processed conserves system resources and prevents wasted processing time. This optimization is particularly important in high-throughput systems where efficiency is critical.
Technical Implementation
The DISCARD command works by:
Authenticating the client using their client ID
Verifying that the client is currently processing the specified event
Permanently removing the event from the processing queue
Recording the discard operation with the provided reason for audit purposes
Notifying the client that the event has been successfully discarded
This implementation ensures that only authorized clients can discard events they are currently processing, maintaining system integrity and security.
Integration Points
The DISCARD command integrates with:
Authentication System: Verifies client identity and permissions
Event Processing System: Removes events from the processing pipeline
Audit System: Records all discard operations with their reasons
Monitoring System: Tracks discard rates and patterns for system health analysis
Use Cases
Handling duplicate events detected by business logic
Removing events with invalid or malformed data
Managing events that cannot be processed due to business rule violations
Implementing dead-letter patterns for unprocessable events
Cleaning up test or development events in production systems