Overview
- Uses JSON filter policies to control which messages each subscription receives.
- A subscription without a filter policy receives all messages.
- Filtering is evaluated server-side by SNS before delivery.
Example
Message published:
- SQS (Placed orders) →
State: Placed.
- Email (Cancelled orders) →
State: Cancelled.
- SQS (Declined orders) →
State: Declined.
- SQS (All) → no filter policy, gets every message.
Benefit
- Enables targeted delivery to relevant consumers.
- Reduces unnecessary processing and network usage.