47 行
1.8 KiB
JavaScript
47 行
1.8 KiB
JavaScript
'use strict'
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/**
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* 安全协议唯一使用的 canonical JSON。对象键按字典序排列，null/undefined 字段省略；
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* 非 JSON 协议值、数组空位和不确定的对象形态直接拒绝。
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*/
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function canonicalJson(value) {
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if (value === null) return 'null'
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if (typeof value === 'string' || typeof value === 'boolean') return JSON.stringify(value)
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if (typeof value === 'number') {
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if (!Number.isFinite(value)) throw new TypeError('Canonical JSON requires finite numbers')
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return JSON.stringify(value)
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}
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if (Array.isArray(value)) {
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for (let index = 0; index < value.length; index += 1) {
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if (!Object.prototype.hasOwnProperty.call(value, index) || value[index] === undefined) {
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throw new TypeError('Canonical JSON arrays cannot contain holes or undefined')
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}
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}
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return `[${value.map(canonicalJson).join(',')}]`
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}
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if (value && typeof value === 'object') {
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const prototype = Object.getPrototypeOf(value)
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if (prototype !== Object.prototype && prototype !== null) {
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throw new TypeError('Canonical JSON only supports plain objects')
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}
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const keys = Reflect.ownKeys(value)
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if (keys.some(key => typeof key === 'symbol')) {
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throw new TypeError('Canonical JSON does not support symbol keys')
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}
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for (const key of keys) {
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const descriptor = Object.getOwnPropertyDescriptor(value, key)
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if (!descriptor?.enumerable || !('value' in descriptor)) {
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throw new TypeError('Canonical JSON only supports enumerable data properties')
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}
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}
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return `{${keys
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.filter(key => value[key] !== null && value[key] !== undefined)
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.sort()
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.map(key => `${JSON.stringify(key)}:${canonicalJson(value[key])}`)
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.join(',')}}`
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}
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throw new TypeError(`Canonical JSON does not support ${typeof value}`)
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}
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module.exports = { canonicalJson }
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