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Solana: “onLogs” listener FAQs – listening for “processed”, “confirmed”, and “finalized” messages
As a Solana developer, you probably know how important it is to handle events efficiently and reliably. One way to achieve this is by using event listeners. A listener is a function that responds to specific events or messages after the event has been processed on the blockchain. In this article, we will look at some frequently asked questions related to Solana’s “onLogs” listener.
What are “onLogs” listeners?
OnSolana, also known as “onLogs”, is an event system that allows developers to create custom listeners that respond to specific events after the event has been processed on the blockchain. These listeners can be used to notify other applications about the status of an event, such as whether it succeeded or failed.
Listen to “processed”
When listening to “processed” events, you want to know that the event has completed and its outcome is available. In Solana, this event is sent when the transaction has been fully processed and confirmed by the node.
However, if you use an “onProcessed” listener, it will only fire after all processing steps have completed, which can lead to unnecessary delays or retries. To minimize latency, consider listening to “confirmed” events instead.
Listen to “confirmed”
When listening to “confirmed” events, you want to know that the event has been successfully processed and its outcome is available. In Solana, this event is sent when the transaction has been completed and confirmed by the node.
Using an OnConfirmed listener can be a good solution if you need to react quickly after the event has started processing.
Listen to “finalized”
When listening to “final” events, you want to make sure that the event has been fully processed and that its outcome is available. In Solana, this event is sent after all processing steps have been completed, including signing, sending, and acknowledging.
Using the OnFinalized listener can be a good solution if you need to react quickly after the event has been handled.
Additional Considerations
Before choosing an event type, consider the following factors:
- Latency requirements: If immediate response is critical, listen to “processed” events.
- Event order: Listen to “acknowledged” or “final” events first to make sure the order of events is correct.
- Additional context: To get a more complete picture, consider additional context about the event outcome.
Conclusion
The Solana event system makes it easy to create custom listeners that react to specific events after they have been processed. By choosing the right event type and considering latency requirements, developers can create efficient and reliable event processing solutions for Solana.
If you are building an event-handling solution for your application, be sure to review the available event types and choose the option that best suits your use case.