Node Flow

Node Flow is runtime-agnostic, composable, asynchronous node-based framework for building structured and reusable data processing pipelines, workflows, or control flows.

The core idea is that each node represents a self-contained asynchronous operation, and flows define how multiple nodes are composed and executed.

Example

use node_flow::node::{Node, NodeOutput};
use node_flow::flows::SequentialFlow;

// Example node
#[derive(Clone)]
struct AddOne;

struct ExampleCtx;

impl<Ctx: Send> Node<u8, NodeOutput<u8>, (), Ctx> for AddOne {
    async fn run(&mut self, input: u8, _: &mut Ctx) -> Result<NodeOutput<u8>, ()> {
        Ok(NodeOutput::Ok(input + 1))
    }
}

async fn main() {
    let mut flow = SequentialFlow::<u8, u8, (), _>::builder()
        .add_node(AddOne)
        .add_node(AddOne)
        .add_node(AddOne)
        .build();

    let mut ctx = ExampleCtx;
    let result = flow.run(5u8, &mut ctx).await;
    assert_eq!(result, Ok(NodeOutput::Ok(8)));
}

When to use Node Flow

Use this crate when you need:

• Composable async control flows (e.g., fallback chains, parallel processing).
• Declarative and type-safe node composition.
• Inspectable or visualizable flow structures.