Hello JSON

The smallest canonical Pulse project: branch on the request path and return JSON or text.

Code

Handler

import { Pulse } from '@pulse-compute/pulse'

const app = new Pulse({ auto: true })

app.get('/health', async (ctx) => ctx.json({ ok: true }))
app.get('/hello', async (ctx) => ctx.json({ message: 'hello from Pulse' }))
app.get('/*', async (ctx) => ctx.text('not found', { status: 404 }))

export default app

Project config

import { defineConfig } from '@pulse-compute/pulse'

export default defineConfig((_scope) => ({
  pulse: {
    entry: 'src/index.ts',
    tests: 'tests/pulse.harness.ts',
    defaultProfile: 'local',
    strict: true,
  },
  local: {
    host: 'node',
    target: 'native',
    outDir: 'dist',
    dev: { host: '127.0.0.1', port: 8787 },
  },
}))

Request and response

Generated from the executable test harness below; these are tested requests or event frames, not an exhaustive application specification. Expected errors and emitted events are included; fixtures and provider setup remain in the harness.

Request	Expected response
health GET /health	{"status":200,"json":{"ok":true}}
hello GET /hello	{"status":200,"json":{"message":"hello from Pulse"}}
missing GET /missing	{"status":404,"text":"not found"}

Inspect

npm run inspect

Inspect describes the configured Node Native target and the recognized response capabilities. This is a selected JSON excerpt; paths, hashes and other fields are omitted.

npm run inspect -- --json

{
  "status": "ok",
  "project": { "target": "native" },
  "provider": { "id": "node" },
  "compiler": { "capabilities": ["response.json", "response.text"] }
}

Doctor

npm run doctor

Doctor checks the project and its local toolchain before execution. This selected result is checked by the documentation gate; it is not a promise about another machine.

npm run doctor -- --json

{
  "status": "passed",
  "summary": { "warnings": 0, "failed": 0 }
}

Report

Build into a separate directory, then review the retained evidence. The report reads the completed artifact without rebuilding or running the application. This selected excerpt accounts for all three registered handlers in the build evidence; timings, paths, hashes and optional evidence are deliberately not presented as stable output.

npm run build -- --out .pulse-docs-build
npm exec -- pulse report --artifact .pulse-docs-build/pulse-build.json --json

{
  "kind": "pulse.application-report",
  "reportVersion": 1,
  "analytics": {
    "coverage": {
      "handlers": { "expected": 3, "observed": 3, "status": "complete" }
    }
  }
}

Optional offline HTML uses the same retained artifact:

npm exec -- pulse report --artifact .pulse-docs-build/pulse-build.json --html

Reports are build-review artifacts; review their contents before sharing. Missing, stale or incompatible evidence is an error, not permission to invent a report.

Interactive report captured from this example at source e69e4b6f1381. Build evidence describes this captured build, not a runtime guarantee.

Open full report · Capture provenance

Workflow

Run commands from this example directory after installing the repository dependencies. The npm scripts use the project-local CLI; Inspect and Doctor commands are shown with their results above.

npm test
npm run dev

While the foreground server is running, request http://127.0.0.1:8787/health or /hello. Stop it with Ctrl+C before building:

npm run build

Test result

The documented test result below is executed by the documentation gate.

pulse test --json

{
  "status": "passed",
  "provider": "node",
  "summary": {
    "total": 3,
    "passed": 3,
    "failed": 0
  },
  "cases": [
    {
      "name": "health",
      "status": "passed",
      "response": {
        "status": 200
      }
    }
  ]
}

Test harness

export default {
  cases: [
    {
      name: 'health',
      request: { path: '/health' },
      expect: { status: 200, json: { ok: true } },
    },
    {
      name: 'hello',
      request: { path: '/hello' },
      expect: {
        status: 200,
        json: { message: 'hello from Pulse' },
      },
    },
    {
      name: 'missing',
      request: { path: '/missing' },
      expect: { status: 404, text: 'not found' },
    },
  ],
}

Wasm size

For build settings, see Native build optimization.

Artifact	Default build
Portable guest canonical-native.wasm	2.2 KiB (2,273 bytes)

The executable documentation gate rebuilds and measures the default artifact. Measured with Node 24.18.0 and lockfile-pinned AssemblyScript 0.28.18. These are uncompressed on-disk sizes, not transfer sizes or platform limits.