nostr-tools/event.ts

126 lines
3.5 KiB
TypeScript

import { schnorr } from '@noble/curves/secp256k1'
import { sha256 } from '@noble/hashes/sha256'
import { bytesToHex } from '@noble/hashes/utils'
import { getPublicKey } from './keys.ts'
import { utf8Encoder } from './utils.ts'
/** @deprecated Use numbers instead. */
/* eslint-disable no-unused-vars */
export enum Kind {
Metadata = 0,
Text = 1,
RecommendRelay = 2,
Contacts = 3,
EncryptedDirectMessage = 4,
EventDeletion = 5,
Repost = 6,
Reaction = 7,
BadgeAward = 8,
ChannelCreation = 40,
ChannelMetadata = 41,
ChannelMessage = 42,
ChannelHideMessage = 43,
ChannelMuteUser = 44,
Blank = 255,
Report = 1984,
ZapRequest = 9734,
Zap = 9735,
RelayList = 10002,
ClientAuth = 22242,
HttpAuth = 27235,
ProfileBadge = 30008,
BadgeDefinition = 30009,
Article = 30023,
FileMetadata = 1063,
}
export type EventTemplate<K extends number = number> = {
kind: K
tags: string[][]
content: string
created_at: number
}
export type UnsignedEvent<K extends number = number> = EventTemplate<K> & {
pubkey: string
}
export type Event<K extends number = number> = UnsignedEvent<K> & {
id: string
sig: string
}
export function getBlankEvent(): EventTemplate<Kind.Blank>
export function getBlankEvent<K extends number>(kind: K): EventTemplate<K>
export function getBlankEvent<K>(kind: K | Kind.Blank = Kind.Blank) {
return {
kind,
content: '',
tags: [],
created_at: 0,
}
}
export function finishEvent<K extends number = number>(t: EventTemplate<K>, privateKey: string): Event<K> {
let event = t as Event<K>
event.pubkey = getPublicKey(privateKey)
event.id = getEventHash(event)
event.sig = getSignature(event, privateKey)
return event
}
export function serializeEvent(evt: UnsignedEvent<number>): string {
if (!validateEvent(evt)) throw new Error("can't serialize event with wrong or missing properties")
return JSON.stringify([0, evt.pubkey, evt.created_at, evt.kind, evt.tags, evt.content])
}
export function getEventHash(event: UnsignedEvent<number>): string {
let eventHash = sha256(utf8Encoder.encode(serializeEvent(event)))
return bytesToHex(eventHash)
}
const isRecord = (obj: unknown): obj is Record<string, unknown> => obj instanceof Object
export function validateEvent<T>(event: T): event is T & UnsignedEvent<number> {
if (!isRecord(event)) return false
if (typeof event.kind !== 'number') return false
if (typeof event.content !== 'string') return false
if (typeof event.created_at !== 'number') return false
if (typeof event.pubkey !== 'string') return false
if (!event.pubkey.match(/^[a-f0-9]{64}$/)) return false
if (!Array.isArray(event.tags)) return false
for (let i = 0; i < event.tags.length; i++) {
let tag = event.tags[i]
if (!Array.isArray(tag)) return false
for (let j = 0; j < tag.length; j++) {
if (typeof tag[j] === 'object') return false
}
}
return true
}
export function verifySignature(event: Event<number>): boolean {
try {
return schnorr.verify(event.sig, getEventHash(event), event.pubkey)
} catch (err) {
return false
}
}
/** @deprecated Use `getSignature` instead. */
export function signEvent(event: UnsignedEvent<number>, key: string): string {
console.warn(
'nostr-tools: `signEvent` is deprecated and will be removed or changed in the future. Please use `getSignature` instead.',
)
return getSignature(event, key)
}
/** Calculate the signature for an event. */
export function getSignature(event: UnsignedEvent<number>, key: string): string {
return bytesToHex(schnorr.sign(getEventHash(event), key))
}