Background Services
Background services are optional components in the Blueprint Runner architecture that run continuously to support the operation of your Actively Validated Service (AVS). This document explains how background services work, how to configure them, and best practices for implementation.
What are Background Services?
Background services refer to any long-running processes that operate independently of job execution. They:
- Run continuously in the background
- Can perform periodic or ongoing tasks
- Might maintain state or connections
- Support the overall operation of the Blueprint Runner
Unlike job handlers that execute in response to specific requests, background services operate autonomously to provide supporting functionality.
Common Use Cases
Background services could be used for various purposes in Blueprints, with the following being only a few examples:
Data Collection and Aggregation
Services that collect and aggregate data, such as an aggregator that submits aggregated signatures to a Blockchain.
Monitoring and Health Checks
Services that monitor the state of something, such as a health checker that verifies that a Blueprint is running.
Background Service Configuration
Background services are typically configured in the main.rs file of your Blueprint binary, when building the Blueprint Runner. The configuration involves:
Basic Background Service Setup
The only requirement for a background service is that it implements the BackgroundService trait:
With a background service defined, it is passed into the Blueprint Runner’s builder as producers and consumers are:
For some background services, it may be necessary to add some sort of cleanup code that runs when the Blueprint Runner shuts down. This can be done in the with_shutdown_handler method seen in the above code. This specific example just prints a message, but it might end a background process gracefully.
Integration with Other Components
Background services work closely with other Blueprint Runner components:
- Routers: Background services may provide support for routers, such as caching or state management
- Producers: Background services can support producers by maintaining connections or monitoring event sources
- Consumers: Background services can assist consumers with resource management or periodic tasks
Next Steps
Now that you understand background services, it might be helpful to take a look at:
- Routers - How to direct job calls to appropriate handlers
- Producers - How to capture and process events
- Consumers - How to handle job results
- Building a Blueprint Runner - Step-by-step guide to building your own Blueprint Runner
Conclusion
Background services are powerful components that enhance the capabilities of your Blueprint Runner by providing continuous support operations. By implementing well-designed background services, you can build more robust, efficient, and feature-rich Blueprints.