379 lines
8.7 KiB
JavaScript
379 lines
8.7 KiB
JavaScript
/*
|
|
MIT License http://www.opensource.org/licenses/mit-license.php
|
|
Author Tobias Koppers @sokra
|
|
*/
|
|
|
|
"use strict";
|
|
|
|
const { SyncHook } = require("tapable");
|
|
|
|
/**
|
|
* @typedef {Object} RuleCondition
|
|
* @property {string | string[]} property
|
|
* @property {boolean} matchWhenEmpty
|
|
* @property {function(string): boolean} fn
|
|
*/
|
|
|
|
/**
|
|
* @typedef {Object} Condition
|
|
* @property {boolean} matchWhenEmpty
|
|
* @property {function(string): boolean} fn
|
|
*/
|
|
|
|
/**
|
|
* @typedef {Object} CompiledRule
|
|
* @property {RuleCondition[]} conditions
|
|
* @property {(Effect|function(object): Effect[])[]} effects
|
|
* @property {CompiledRule[]=} rules
|
|
* @property {CompiledRule[]=} oneOf
|
|
*/
|
|
|
|
/**
|
|
* @typedef {Object} Effect
|
|
* @property {string} type
|
|
* @property {any} value
|
|
*/
|
|
|
|
/**
|
|
* @typedef {Object} RuleSet
|
|
* @property {Map<string, any>} references map of references in the rule set (may grow over time)
|
|
* @property {function(object): Effect[]} exec execute the rule set
|
|
*/
|
|
|
|
class RuleSetCompiler {
|
|
constructor(plugins) {
|
|
this.hooks = Object.freeze({
|
|
/** @type {SyncHook<[string, object, Set<string>, CompiledRule, Map<string, any>]>} */
|
|
rule: new SyncHook([
|
|
"path",
|
|
"rule",
|
|
"unhandledProperties",
|
|
"compiledRule",
|
|
"references"
|
|
])
|
|
});
|
|
if (plugins) {
|
|
for (const plugin of plugins) {
|
|
plugin.apply(this);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @param {object[]} ruleSet raw user provided rules
|
|
* @returns {RuleSet} compiled RuleSet
|
|
*/
|
|
compile(ruleSet) {
|
|
const refs = new Map();
|
|
const rules = this.compileRules("ruleSet", ruleSet, refs);
|
|
|
|
/**
|
|
* @param {object} data data passed in
|
|
* @param {CompiledRule} rule the compiled rule
|
|
* @param {Effect[]} effects an array where effects are pushed to
|
|
* @returns {boolean} true, if the rule has matched
|
|
*/
|
|
const execRule = (data, rule, effects) => {
|
|
for (const condition of rule.conditions) {
|
|
const p = condition.property;
|
|
if (Array.isArray(p)) {
|
|
let current = data;
|
|
for (const subProperty of p) {
|
|
if (
|
|
current &&
|
|
typeof current === "object" &&
|
|
Object.prototype.hasOwnProperty.call(current, subProperty)
|
|
) {
|
|
current = current[subProperty];
|
|
} else {
|
|
current = undefined;
|
|
break;
|
|
}
|
|
}
|
|
if (current !== undefined) {
|
|
if (!condition.fn(current)) return false;
|
|
continue;
|
|
}
|
|
} else if (p in data) {
|
|
const value = data[p];
|
|
if (value !== undefined) {
|
|
if (!condition.fn(value)) return false;
|
|
continue;
|
|
}
|
|
}
|
|
if (!condition.matchWhenEmpty) {
|
|
return false;
|
|
}
|
|
}
|
|
for (const effect of rule.effects) {
|
|
if (typeof effect === "function") {
|
|
const returnedEffects = effect(data);
|
|
for (const effect of returnedEffects) {
|
|
effects.push(effect);
|
|
}
|
|
} else {
|
|
effects.push(effect);
|
|
}
|
|
}
|
|
if (rule.rules) {
|
|
for (const childRule of rule.rules) {
|
|
execRule(data, childRule, effects);
|
|
}
|
|
}
|
|
if (rule.oneOf) {
|
|
for (const childRule of rule.oneOf) {
|
|
if (execRule(data, childRule, effects)) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
return true;
|
|
};
|
|
|
|
return {
|
|
references: refs,
|
|
exec: data => {
|
|
/** @type {Effect[]} */
|
|
const effects = [];
|
|
for (const rule of rules) {
|
|
execRule(data, rule, effects);
|
|
}
|
|
return effects;
|
|
}
|
|
};
|
|
}
|
|
|
|
/**
|
|
* @param {string} path current path
|
|
* @param {object[]} rules the raw rules provided by user
|
|
* @param {Map<string, any>} refs references
|
|
* @returns {CompiledRule[]} rules
|
|
*/
|
|
compileRules(path, rules, refs) {
|
|
return rules.map((rule, i) =>
|
|
this.compileRule(`${path}[${i}]`, rule, refs)
|
|
);
|
|
}
|
|
|
|
/**
|
|
* @param {string} path current path
|
|
* @param {object} rule the raw rule provided by user
|
|
* @param {Map<string, any>} refs references
|
|
* @returns {CompiledRule} normalized and compiled rule for processing
|
|
*/
|
|
compileRule(path, rule, refs) {
|
|
const unhandledProperties = new Set(
|
|
Object.keys(rule).filter(key => rule[key] !== undefined)
|
|
);
|
|
|
|
/** @type {CompiledRule} */
|
|
const compiledRule = {
|
|
conditions: [],
|
|
effects: [],
|
|
rules: undefined,
|
|
oneOf: undefined
|
|
};
|
|
|
|
this.hooks.rule.call(path, rule, unhandledProperties, compiledRule, refs);
|
|
|
|
if (unhandledProperties.has("rules")) {
|
|
unhandledProperties.delete("rules");
|
|
const rules = rule.rules;
|
|
if (!Array.isArray(rules))
|
|
throw this.error(path, rules, "Rule.rules must be an array of rules");
|
|
compiledRule.rules = this.compileRules(`${path}.rules`, rules, refs);
|
|
}
|
|
|
|
if (unhandledProperties.has("oneOf")) {
|
|
unhandledProperties.delete("oneOf");
|
|
const oneOf = rule.oneOf;
|
|
if (!Array.isArray(oneOf))
|
|
throw this.error(path, oneOf, "Rule.oneOf must be an array of rules");
|
|
compiledRule.oneOf = this.compileRules(`${path}.oneOf`, oneOf, refs);
|
|
}
|
|
|
|
if (unhandledProperties.size > 0) {
|
|
throw this.error(
|
|
path,
|
|
rule,
|
|
`Properties ${Array.from(unhandledProperties).join(", ")} are unknown`
|
|
);
|
|
}
|
|
|
|
return compiledRule;
|
|
}
|
|
|
|
/**
|
|
* @param {string} path current path
|
|
* @param {any} condition user provided condition value
|
|
* @returns {Condition} compiled condition
|
|
*/
|
|
compileCondition(path, condition) {
|
|
if (condition === "") {
|
|
return {
|
|
matchWhenEmpty: true,
|
|
fn: str => str === ""
|
|
};
|
|
}
|
|
if (!condition) {
|
|
throw this.error(
|
|
path,
|
|
condition,
|
|
"Expected condition but got falsy value"
|
|
);
|
|
}
|
|
if (typeof condition === "string") {
|
|
return {
|
|
matchWhenEmpty: condition.length === 0,
|
|
fn: str => str.startsWith(condition)
|
|
};
|
|
}
|
|
if (typeof condition === "function") {
|
|
try {
|
|
return {
|
|
matchWhenEmpty: condition(""),
|
|
fn: condition
|
|
};
|
|
} catch (err) {
|
|
throw this.error(
|
|
path,
|
|
condition,
|
|
"Evaluation of condition function threw error"
|
|
);
|
|
}
|
|
}
|
|
if (condition instanceof RegExp) {
|
|
return {
|
|
matchWhenEmpty: condition.test(""),
|
|
fn: v => condition.test(v)
|
|
};
|
|
}
|
|
if (Array.isArray(condition)) {
|
|
const items = condition.map((c, i) =>
|
|
this.compileCondition(`${path}[${i}]`, c)
|
|
);
|
|
return this.combineConditionsOr(items);
|
|
}
|
|
|
|
if (typeof condition !== "object") {
|
|
throw this.error(
|
|
path,
|
|
condition,
|
|
`Unexpected ${typeof condition} when condition was expected`
|
|
);
|
|
}
|
|
|
|
const conditions = [];
|
|
for (const key of Object.keys(condition)) {
|
|
const value = condition[key];
|
|
switch (key) {
|
|
case "or":
|
|
if (value) {
|
|
if (!Array.isArray(value)) {
|
|
throw this.error(
|
|
`${path}.or`,
|
|
condition.and,
|
|
"Expected array of conditions"
|
|
);
|
|
}
|
|
conditions.push(this.compileCondition(`${path}.or`, value));
|
|
}
|
|
break;
|
|
case "and":
|
|
if (value) {
|
|
if (!Array.isArray(value)) {
|
|
throw this.error(
|
|
`${path}.and`,
|
|
condition.and,
|
|
"Expected array of conditions"
|
|
);
|
|
}
|
|
let i = 0;
|
|
for (const item of value) {
|
|
conditions.push(this.compileCondition(`${path}.and[${i}]`, item));
|
|
i++;
|
|
}
|
|
}
|
|
break;
|
|
case "not":
|
|
if (value) {
|
|
const matcher = this.compileCondition(`${path}.not`, value);
|
|
const fn = matcher.fn;
|
|
conditions.push({
|
|
matchWhenEmpty: !matcher.matchWhenEmpty,
|
|
fn: v => !fn(v)
|
|
});
|
|
}
|
|
break;
|
|
default:
|
|
throw this.error(
|
|
`${path}.${key}`,
|
|
condition[key],
|
|
`Unexpected property ${key} in condition`
|
|
);
|
|
}
|
|
}
|
|
if (conditions.length === 0) {
|
|
throw this.error(
|
|
path,
|
|
condition,
|
|
"Expected condition, but got empty thing"
|
|
);
|
|
}
|
|
return this.combineConditionsAnd(conditions);
|
|
}
|
|
|
|
/**
|
|
* @param {Condition[]} conditions some conditions
|
|
* @returns {Condition} merged condition
|
|
*/
|
|
combineConditionsOr(conditions) {
|
|
if (conditions.length === 0) {
|
|
return {
|
|
matchWhenEmpty: false,
|
|
fn: () => false
|
|
};
|
|
} else if (conditions.length === 1) {
|
|
return conditions[0];
|
|
} else {
|
|
return {
|
|
matchWhenEmpty: conditions.some(c => c.matchWhenEmpty),
|
|
fn: v => conditions.some(c => c.fn(v))
|
|
};
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @param {Condition[]} conditions some conditions
|
|
* @returns {Condition} merged condition
|
|
*/
|
|
combineConditionsAnd(conditions) {
|
|
if (conditions.length === 0) {
|
|
return {
|
|
matchWhenEmpty: false,
|
|
fn: () => false
|
|
};
|
|
} else if (conditions.length === 1) {
|
|
return conditions[0];
|
|
} else {
|
|
return {
|
|
matchWhenEmpty: conditions.every(c => c.matchWhenEmpty),
|
|
fn: v => conditions.every(c => c.fn(v))
|
|
};
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @param {string} path current path
|
|
* @param {any} value value at the error location
|
|
* @param {string} message message explaining the problem
|
|
* @returns {Error} an error object
|
|
*/
|
|
error(path, value, message) {
|
|
return new Error(
|
|
`Compiling RuleSet failed: ${message} (at ${path}: ${value})`
|
|
);
|
|
}
|
|
}
|
|
|
|
module.exports = RuleSetCompiler;
|