FusionConfig
fusion.<env>.json and settings in Node.js
Overview
Runtime config is shared with Python: JSON files named fusion.<env>.json, selected by FUSION_ENV (default dev).
import { settings, getSettings, configure } from "fusion-framework";
settings.ensureLoaded([process.cwd()]);
const host = settings.host;
const debug = settings.get("debug", false);Startup pattern
settings.ensureLoaded([process.cwd()]);
const app = new FusionApp(getSettings());
await app.listen();FusionApp listens on host / port from settings unless you pass overrides to listen(host, port).
API
| API | Role |
|---|---|
settings.ensureLoaded(extraRoots?) | Discover and load fusion.<env>.json |
settings.loadJson(path?, env?, extraRoots?) | Explicit path / env |
settings.get(key, default?) | Nested key lookup |
settings.merge(object) | Overlay values |
configure(object) | Merge into the singleton |
getSettings() | { host, port, debug, env } snapshot for FusionApp |
Env placeholders in JSON (UPPERCASE strings) resolve from process environment — same rules as Python.
File shape
{
"env": "dev",
"config": {
"host": "127.0.0.1",
"port": 3000,
"debug": true,
"secret_key": "SECRET_KEY"
},
"commands": {
"run": "npx tsx main.ts"
}
}commands are for Fusion Tool, not the HTTP runtime.