@orkestrel/rater

A typed quantitative rating layer over @orkestrel/reason's shared engine: authored lines, each a plain reason QuantitativeDefinition joined to display metadata, rated against one subject to produce a LineResult per line — an amount and its Worksheet audit trail — and one RatingResult carrying every line's outcome and a derived total.

Create a rater with the createRater function, hand it the lines a subject is rated against, and read the LineResult rows and the total it derives. Inject a @orkestrel/reason ReasonInterface where the rating shares an engine with the rest of your reasoning, and call destroy() when the rater's work is done. Environment-agnostic — no I/O, no browser or server assumptions. Part of the @orkestrel line.

Install

npm install @orkestrel/rater

Requirements

• Node.js >= 22.12.0
• ESM (import) and CommonJS (require) through the exports field

Usage

import { buildLineDefinition, createRater } from '@orkestrel/rater'
import {
	createFactorGroup,
	createQuantitativeDefinition,
	createStaticFactor,
} from '@orkestrel/reason'

const rater = createRater()

const base = buildLineDefinition(
	'base',
	'Base Amount',
	createQuantitativeDefinition('base', 'Base', [
		createFactorGroup('amount', 'sum', [createStaticFactor('flat', 100)]),
	]),
)

const result = rater.rate([base], { id: 'subject-1' })
result.lines[0]?.amount // 100
result.total // 100

rater.emitter.on('rate', (subject, rated) => rated.success)

rater.destroy()

rate accepts a plain LineDefinition[] or a full RatingDefinition plus one subject, and each overload rates that single subject. Every rate call fires once through rater.emitter (rate).

Guide

For the full surface — Rater, RatingResult, worksheet types, validators, factories, errors, and options — see guides/rater.md.

Package

Published as a single typed entry point per the exports field in package.json.

License

MIT © Orkestrel — see LICENSE.