Declarative Workflows

Flowcraft allows defining workflows using JSON blueprints, decoupling structure from implementation. The primary difference from programmatic workflows is separating the WorkflowBlueprint (the JSON structure) from the NodeRegistry (the code implementations), which allows for dynamic workflow generation or storage in a database.

Node Registry

First, create a registry of reusable node functions.

const nodeRegistry = {
	takeOrderFn: async ({ context }) => {
		const order = { item: 'Coffee', size: 'Medium' }
		await context.set('order', order)
		return { output: order }
	},
	makeDrinkFn: async ({ input, context }) => {
		const order = input as { item: string; size: string }
		return { output: `Made ${order.size} ${order.item}` }
	},
	serveCustomerFn: async ({ input }) => {
		return { output: `Served: ${input}` }
	},
}

Workflow Blueprint

Define the workflow as a JSON object.

{
	"id": "coffee-shop-order",
	"nodes": [
		{
			"id": "take-order",
			"uses": "takeOrderFn"
		},
		{
			"id": "make-drink",
			"uses": "makeDrinkFn",
			"inputs": "take-order"
		},
		{
			"id": "serve-customer",
			"uses": "serveCustomerFn",
			"inputs": "make-drink"
		}
	],
	"edges": [
		{
			"source": "take-order",
			"target": "make-drink"
		},
		{
			"source": "make-drink",
			"target": "serve-customer"
		}
	]
}

Execution

Load and run the blueprint with the registry.

import { FlowRuntime } from 'flowcraft'

const runtime = new FlowRuntime({ registry: nodeRegistry })
const result = await runtime.run(
	blueprint,
	{
		/* Initial context */
	},
	{ functionRegistry: nodeRegistry },
)

This approach separates workflow structure from code, enabling dynamic configurations.

Demo

This workflow can be visualized and run in the demo below:

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Press enter or space to select a node. You can then use the arrow keys to move the node around. You can then use the arrow keys to move the node around, press delete to remove it and press escape to cancel.

Press enter or space to select an edge. You can then press delete to remove it or press escape to cancel.