README.md

Core

The Core was created to load and manage SlimIO addons, it will create/handle communication between each addons.

Each addon are isolated from each others (designed like container above). You may be interested by the Gate addon as well if you want to learn how the core work and behave at higher level.

Requirements

• Node.js v12 or higher

Features / Roles

• (Re)loading addons.
• Manage communication between addons.
• Retention of communications in case of anomalies.
• Monitoring isolation.

The core as clean and well defined roles to be as much stable possible. Behavior related to addons communication and data exposition will be all related to the Gate addon (which is the right hand of the core). As an addon there is no way to talk to the core directly.

Getting Started

This package is available in the Node Package Repository and can be easily installed with npm or yarn.

$ npm i @slimio/core
# or
$ yarn add @slimio/core

Usage example

A script that demonstrate how to load a default core (Configuration will be created dynamically).

import "make-promises-safe";

import { fileURLToPath } from 'url';
import { dirname } from 'path';

import Core from "@slimio/core";

const __filename = fileURLToPath(import.meta.url);
const __dirname = dirname(__filename);

async function main() {
    console.time("start_core");
    const core = await (new Core(__dirname)).initialize();
    console.timeEnd("start_core");

    // Handle exit signal!
    process.on("SIGINT", () => {
        console.error("Exiting SlimIO Agent (please wait)");
        core.exit().then(() => {
            setImmediate(process.exit);
        }).catch(function mainErrorHandler(error) {
            console.error(error);
            process.exit(1);
        });
    });
}
main().catch(console.error);

👀 Not that we use make-promises-safe to enforce Node.js DEP 00018.

Global

The core register himself as a global with the name slimio_core.

console.log(global.slimio_core);

The current core version is also available as global.coreVersion.

API

constructor(dirname: string, options?: Core.ConstructorOptions)

Create a new instance of Core Object. The argument dirname is the root directory where the core have to load his configuration and all addons.

The constructor take an optional options object which contain all options to configure the core Agent.

interface ConstructorOptions {
    silent?: boolean;
    autoReload?: number;
    toml?: boolean;
}

initialize(): Promise< this >

Initialize the Core (it will load configuration and addons). The loading of addons is lazy, so the response will be returned before the addons have had time to fully load.

searchForLockedAddons(addonName: string): IterableIterator< string >

Search locked addons for a given addonName.

exit(): Promise< void >

Stop the core and all affiliated ressources (addons, config etc..).

Note: Think to exit the process with an iteration + 1 (with setImmediate).

Dependencies

Name	Refactoring	Security Risk	Usage
@slimio/addon	⚠️Major	High	Addon default class
@slimio/config	Minor	High	Configuration interaction
@slimio/ipc	⚠️Major	High	Inter-process communication
@slimio/is	Minor	Low	Type checker
@slimio/logger	Minor	Low	Sonic Logger with low overhead for SlimIO
@slimio/safe-emitter	Minor	High	Safe emittter
@slimio/scheduler	Minor	Low	Scheduler
@slimio/utils	Minor	High	Bunch of useful functions
is-stream	Minor	Low	TBC
make-promises-safe	⚠️Major	High	Promise not exit process when fail
semver	⚠️Major	Low	Semver parser/utilities for node
@lukeed/uuid	Minor	Low	A tiny (230B), fast, and cryptographically secure UUID (v4) generator for Node and the browser

License

MIT