Inspecting your app

Your composition spans many files. .graph() returns it as a JSON tree — log it, render it as a diagram, feed it to an LLM. Or snapshot it to catch unintended changes.

Inspecting

Call .graph() to get the tree without executing Tasks.

Output:

{
  "type": "seq",
  "meta": {},
  "children": [
    {
      "type": "run",
      "meta": { "name": "alpha", "kind": "task" },
      "id": 0,
      "dependencies": { "required": [], "optional": [] }
    }
  ]
}

import {
createWire, compose, tag, createTask, optional
} from "@grlt-hub/app-compose"

const title = tag<string>("title")

const alpha = createTask({
  name: "alpha",
  run: { fn: () => ({ list: [0], title: "hello" }) },
})

const beta = createTask({
  name: "beta",
  run: {
    context: { title: title.value },
    fn: console.log,
  },
})

const gamma = createTask({
  name: "gamma",
  run: {
    context: { list: optional(alpha.result.list) },
    fn: console.log,
  },
})

const app = compose()
  .step(alpha)
  .step([
    compose()
      .step(createWire({ from: alpha.result.title, to: title }))
      .step(beta),
    gamma,
  ])

const graph = app.graph()

console.log(JSON.stringify(graph, null, 2))

Snapshotting the graph

Snapshot .graph() in a test to catch unintended changes.

import { describe, expect, it } from "vitest"
import { app } from "./app"

describe("app graph", () => {
  it("matches snapshot", () => {
    expect(app.graph()).toMatchSnapshot()
  })
})