app/frontend/tests/runtime.spec.ts

import { expect, test } from "@playwright/test"
import { api, apiPage, createFlow, deleteAll } from "./utils/api"

/**
 * Flows can be taken off the engine and put back, and what a node prints — or
 * the traceback of one that fails — is readable without leaving the canvas.
 */

const flowName = `test_runtime_${Date.now().toString(36)}`

test.use({ storageState: "playwright/.auth/user.json" })

test.describe.configure({ mode: "serial" })

const PRINTING_NODE = `def process():
    print("sensor read 21.5 degrees")
    return {"reading": 21.5}
`
const BROKEN_NODE = `def process(reading):
    raise RuntimeError("downstream blew up")
`
const FIXED_NODE = `def process(reading):
    print(f"logged {reading}")
`

test.afterAll(async ({ browser }) => {
  await deleteAll(browser, [`/flows/${flowName}`])
})

test.beforeAll(async ({ browser }) => {
  const page = await apiPage(browser)
  await createFlow(page, {
    name: flowName,
    title: "Runtime",
    nodes: [
      {
        id: "sensor",
        type: "python",
        provides: [{ name: "reading", dtype: "float" }],
      },
      {
        id: "logger",
        type: "python",
        requires: [{ name: "reading", dtype: "float" }],
      },
    ],
  })
  await api(page, `/flows/${flowName}/nodes/sensor/source`, {
    method: "PUT",
    data: { code: PRINTING_NODE },
  })
  await api(page, `/flows/${flowName}/nodes/logger/source`, {
    method: "PUT",
    data: { code: BROKEN_NODE },
  })
  const detail = await (await api(page, `/flows/${flowName}`)).json()
  await api(page, `/flows/${flowName}/publish`, {
    method: "POST",
    data: { version: detail.definition.version },
  })
  await page.close()
})

test("the home page lists flows and can stop one", async ({ page }) => {
  await page.goto("/")
  const row = page.getByTestId("home-flow-row").filter({ hasText: "Runtime" })
  await expect(row).toBeVisible()
  await expect(row).toContainText("Running")

  await row.getByTestId("flow-enabled-switch").click()
  await expect(row).toContainText("Stopped")

  // A stopped flow is not something the engine will run.
  const refused = await api(page, `/flows/${flowName}/run`, {
    method: "POST",
    data: { inputs: {} },
  })
  expect(refused.status()).toBe(409)

  await row.getByTestId("flow-enabled-switch").click()
  await expect(row).toContainText("Running")
})

test("the logs panel shows what a node printed and why one failed", async ({
  page,
}) => {
  await page.goto(`/flows/${flowName}`)
  await page.waitForSelector(".react-flow__node")

  await page.getByTestId("run-flow").click()
  await page.getByTestId("flow-logs").click()

  const panel = page.getByTestId("logs-panel")
  await expect(panel).toContainText("sensor read 21.5 degrees")
  await expect(panel).toContainText("RuntimeError")

  // Reading the logs is something you do *while* working on the flow, so a
  // click on the canvas leaves them up — only the button or Escape closes it.
  await page.locator(".react-flow__pane").click({ position: { x: 8, y: 8 } })
  await expect(panel).toBeVisible()

  // It sits above the dock rather than on it, and shares its centre. The dock
  // has no box of its own to measure, so its span is its first and last
  // buttons; its padding is symmetric, so their midpoint is its centre.
  const logs = (await panel.boundingBox())!
  const dock = (await page.getByTestId("run-flow").boundingBox())!
  expect(logs.y + logs.height).toBeLessThan(dock.y)

  const first = (await page.getByTestId("add-node").boundingBox())!
  const last = (await page.getByTestId("publish-flow").boundingBox())!
  const centre = (first.x + last.x + last.width) / 2
  expect(Math.abs(logs.x + logs.width / 2 - centre)).toBeLessThan(2)

  await page.getByTestId("flow-logs").click()
  await expect(panel).toBeHidden()
})

test("a node's failure outlives its next good run", async ({ page }) => {
  await page.goto(`/flows/${flowName}`)
  await page.waitForSelector(".react-flow__node")

  const logger = page.locator(".react-flow__node").filter({ hasText: "logger" })
  await page.getByTestId("run-flow").click()
  await expect(logger.getByTestId("node-traceback")).toBeVisible()

  // Fix it the way the editor does, and put it on the engine: publishing
  // rebuilds every node, which is exactly what must not wipe the record.
  await api(page, `/flows/${flowName}/nodes/logger/source`, {
    method: "PUT",
    data: { code: FIXED_NODE },
  })
  const detail = await (await api(page, `/flows/${flowName}`)).json()
  await api(page, `/flows/${flowName}/publish`, {
    method: "POST",
    data: { version: detail.definition.version },
  })

  await page.getByTestId("run-flow").click()
  // The dot says how the *last* run went, and the traceback button says the
  // node failed at some point since anyone looked. Both at once is the point.
  await expect(logger.getByLabel("Last run succeeded")).toBeVisible()
  await expect(logger.getByTestId("node-traceback")).toBeVisible()
})

test("a flow can be paused and let go again", async ({ page }) => {
  await page.goto(`/flows/${flowName}`)
  await page.waitForSelector(".react-flow__node")

  await page.getByTestId("pause-flow").click()
  await expect(page.getByTestId("resume-flow")).toBeVisible()
  expect((await (await api(page, `/flows/${flowName}`)).json()).paused).toBe(
    true,
  )

  await page.getByTestId("resume-flow").click()
  await expect(page.getByTestId("pause-flow")).toBeVisible()
})