Producers

Producers are a key component of the Blueprint Runner architecture that capture events and prepare them for processing. This document explains how producers work, how to configure them, and how to implement them.

What are Producers?

In a Blueprint Runner, producers are responsible for:

Listening for events from a given source (e.g., blockchain events, polling calls, etc.)
Preparing events to be passed to a job for processing, with the router

Producers act as the input handlers of your Blueprint Runner, ensuring that external events are properly captured and processed.

Producer Configuration

Producers are typically configured in the main.rs file of your Blueprint binary, when defining the Blueprint Runner. It is a Stream that outputs a JobCall, which is then passed to the router and routed to the appropriate job. A Producer can be made to generate JobCalls from anything, but we have some built-in producers that can be used out of the box.

Basic Producer Setup

First, you define the producer you want to use. For example, a TangleProducer that listens for finalized blocks on Tangle. After which, you pass the producer to the Blueprint Runner’s builder.

let env = BlueprintEnvironment::load()?;
let tangle_client = env.tangle_client().await?;
let tangle_producer = TangleProducer::finalized_blocks(tangle_client.rpc_client.clone()).await?;
 
BlueprintRunner::builder(tangle_config, env)
    .router(router) // Assuming your router is already defined
    .producer(tangle_producer)
    .run()
    .await?;

Types of Producers

Blueprint Runners can utilize various types of producers depending on the event sources:

Blockchain Producers

These producers listen for events from a blockchain, such as smart contract events or finalized blocks.

There are currently two built-in blockchain producers:

Tangle Producer

EVM Polling Producer

Cron Jobs

Integration with Other Components

Producers work closely with other Blueprint Runner components:

Routers: Producers submit JobCalls to their router, where they are routed to the appropriate job
Consumers: JobCalls processed by producers ultimately lead to results handled by consumers

Next Steps

Now that you understand producers, learn about:

Routers - How to direct job calls to appropriate handlers
Consumers - How to handle job results
Building a Blueprint Runner - Step-by-step guide to building your own Blueprint Runner

Conclusion

Producers are essential components that capture and prepare events for processing in your Blueprint Runner. By implementing robust and efficient producers, you can ensure that your Blueprint reliably processes desired events.

Routers Consumers