Press n or j to go to the next uncovered block, b, p or k for the previous block.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 | 16x 16x 16x 16x 16x 16x 16x 8x 8x 8x 7x 7x 24x 24x 24x 1x 23x 23x 1x 22x 22x 1x 21x 24x 24x 24x 21x 21x 1x 20x 24x 20x 20x 1x 19x 19x 19x 19x 18x 1x 17x 24x 1x 16x 16x 14x 2x 19x 1x 18x 6x 12x 12x 1x 11x 11x 11x 11x 12x 12x 12x 10x 9x 9x 9x 8x 4x 12x 12x 12x 12x 19x 19x 8x 11x 31x 31x 31x 31x 31x 3031x 30x 1x 30x 30x 30x 16x 1x 15x 16x 8x 1x 1x 1x 1x 1x 1x 1x 17x | import type {
ChannelFollowEvent,
ChatMessageEvent,
KicksGiftedEvent,
LivestreamStatusUpdatedEvent,
NewSubscriptionEvent,
SubscriptionGiftEvent,
SubscriptionRenewalEvent,
} from "kick-api-types/payloads";
import type { ContentfulStatusCode } from "hono/utils/http-status";
const PUBLIC_KEY_ENDPOINT = "https://api.kick.com/public/v1/public-key";
const DEFAULT_TOLERANCE_SECONDS = 5 * 60;
const HEADER_NAMES = {
messageId: "Kick-Event-Message-Id",
subscriptionId: "Kick-Event-Subscription-Id",
signature: "Kick-Event-Signature",
timestamp: "Kick-Event-Message-Timestamp",
eventType: "Kick-Event-Type",
eventVersion: "Kick-Event-Version",
} as const;
const KICK_PUBLIC_KEY_PEM = `-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAq/+l1WnlRrGSolDMA+A8
6rAhMbQGmQ2SapVcGM3zq8ANXjnhDWocMqfWcTd95btDydITa10kDvHzw9WQOqp2
MZI7ZyrfzJuz5nhTPCiJwTwnEtWft7nV14BYRDHvlfqPUaZ+1KR4OCaO/wWIk/rQ
L/TjY0M70gse8rlBkbo2a8rKhu69RQTRsoaf4DVhDPEeSeI5jVrRDGAMGL3cGuyY
6CLKGdjVEM78g3JfYOvDU/RvfqD7L89TZ3iN94jrmWdGz34JNlEI5hqK8dd7C5EF
BEbZ5jgB8s8ReQV8H+MkuffjdAj3ajDDX3DOJMIut1lBrUVD1AaSrGCKHooWoL2e
twIDAQAB
-----END PUBLIC KEY-----`;
const textEncoder = new TextEncoder();
let cachedCryptoKey: CryptoKey | null = null;
let cachedPemSource: string | null = null;
export type KickWebhookPayload =
| ChatMessageEvent
| ChannelFollowEvent
| SubscriptionRenewalEvent
| SubscriptionGiftEvent
| NewSubscriptionEvent
| LivestreamStatusUpdatedEvent
| KicksGiftedEvent;
export type KickWebhookEventType = KickWebhookPayload["eventType"];
export interface KickWebhookValidationOptions {
/**
* Optional PEM string to override the Kick public key, useful for testing.
*/
publicKeyPEM?: string;
/**
* Maximum allowed age (in seconds) of a webhook message. Defaults to 300s.
*/
toleranceSeconds?: number;
/**
* Provide a custom fetch implementation (handy for unit tests).
*/
fetcher?: typeof fetch;
}
export interface KickWebhookMetadata {
messageId: string;
timestamp: string;
signature: string;
subscriptionId?: string;
eventType: string;
eventVersion: string;
rawBody: string;
}
export type KickWebhookValidationResult =
| ({ knownType: true; payload: KickWebhookPayload } & KickWebhookMetadata)
| ({
knownType: false;
payload: Record<string, unknown>;
} & KickWebhookMetadata);
export class KickWebhookError extends Error {
constructor(message: string, readonly status: ContentfulStatusCode) {
super(message);
this.name = "KickWebhookError";
}
}
export class KickWebhookSignatureError extends KickWebhookError {
constructor(message: string) {
super(message, 403);
this.name = "KickWebhookSignatureError";
}
}
/**
* Validates the incoming Kick webhook request by verifying the RSA signature,
* applying a replay-window tolerance, and returning the typed payload.
*/
export async function validateKickWebhook(
request: Request,
options: KickWebhookValidationOptions = {}
): Promise<KickWebhookValidationResult> {
const headers = request.headers;
const messageId = headers.get(HEADER_NAMES.messageId);
if (!messageId) {
throw new KickWebhookSignatureError("Missing Kick-Event-Message-Id header");
}
const timestamp = headers.get(HEADER_NAMES.timestamp);
if (!timestamp) {
throw new KickWebhookSignatureError(
"Missing Kick-Event-Message-Timestamp header"
);
}
const signatureHeader = headers.get(HEADER_NAMES.signature);
if (!signatureHeader) {
throw new KickWebhookSignatureError("Missing Kick-Event-Signature header");
}
const eventType = headers.get(HEADER_NAMES.eventType) ?? "";
const eventVersion = headers.get(HEADER_NAMES.eventVersion) ?? "1";
const subscriptionId = headers.get(HEADER_NAMES.subscriptionId) ?? undefined;
const rawBody = await request.text();
const timestampMs = Date.parse(timestamp);
if (Number.isNaN(timestampMs)) {
throw new KickWebhookSignatureError(
"Invalid Kick-Event-Message-Timestamp header"
);
}
const toleranceMs = Math.max(
0,
(options.toleranceSeconds ?? DEFAULT_TOLERANCE_SECONDS) * 1000
);
if (toleranceMs > 0) {
const now = Date.now();
if (Math.abs(now - timestampMs) > toleranceMs) {
throw new KickWebhookSignatureError(
"Webhook timestamp outside the allowed tolerance window"
);
}
}
const publicKey = await getKickPublicKey({
publicKeyPEM: options.publicKeyPEM,
fetcher: options.fetcher,
});
const signingPayload = `${messageId}.${timestamp}.${rawBody}`;
const signatureBytes = decodeBase64(normalizeSignature(signatureHeader));
const verified = await crypto.subtle.verify(
{ name: "RSASSA-PKCS1-v1_5" },
publicKey,
toArrayBuffer(signatureBytes),
textEncoder.encode(signingPayload)
);
if (!verified) {
throw new KickWebhookSignatureError(
"Webhook signature verification failed"
);
}
const jsonPayload = rawBody.length ? JSON.parse(rawBody) : {};
if (!isRecord(jsonPayload)) {
throw new KickWebhookError(
"Expected webhook payload to be a JSON object",
400
);
}
const payload = coercePayload(eventType, eventVersion, jsonPayload);
if (payload) {
return {
knownType: true,
payload,
messageId,
timestamp,
signature: signatureHeader,
subscriptionId,
eventType: payload.eventType,
eventVersion: payload.eventVersion,
rawBody,
};
}
return {
knownType: false,
payload: jsonPayload,
messageId,
timestamp,
signature: signatureHeader,
subscriptionId,
eventType,
eventVersion,
rawBody,
};
}
interface PublicKeyOptions {
publicKeyPEM?: string;
fetcher?: typeof fetch;
}
async function getKickPublicKey(options: PublicKeyOptions): Promise<CryptoKey> {
if (options.publicKeyPEM) {
return importPublicKey(options.publicKeyPEM);
}
if (cachedCryptoKey && cachedPemSource === KICK_PUBLIC_KEY_PEM) {
return cachedCryptoKey;
}
const pem = await fetchKickPublicKey(options.fetcher);
if (cachedCryptoKey && pem === cachedPemSource) {
return cachedCryptoKey;
}
const cryptoKey = await importPublicKey(pem);
cachedCryptoKey = cryptoKey;
cachedPemSource = pem;
return cryptoKey;
}
async function fetchKickPublicKey(
fetcher: typeof fetch | undefined
): Promise<string> {
const effectiveFetcher = fetcher ?? fetch;
try {
const response = await effectiveFetcher(PUBLIC_KEY_ENDPOINT, {
headers: { Accept: "application/json" },
});
if (response.ok) {
const data = (await response.json()) as {
data?: { public_key?: string };
};
const pem = data?.data?.public_key;
if (typeof pem === "string" && pem.includes("BEGIN PUBLIC KEY")) {
return pem;
}
}
} catch {
// Ignore network errors and fall back to the embedded key.
}
return KICK_PUBLIC_KEY_PEM;
}
async function importPublicKey(pem: string): Promise<CryptoKey> {
const binaryDer = pemToArrayBuffer(pem);
return crypto.subtle.importKey(
"spki",
binaryDer,
{
name: "RSASSA-PKCS1-v1_5",
hash: "SHA-256",
},
true,
["verify"]
);
}
function pemToArrayBuffer(pem: string): ArrayBuffer {
const b64 = pem
.replace("-----BEGIN PUBLIC KEY-----", "")
.replace("-----END PUBLIC KEY-----", "")
.replace(/\s+/g, "");
return toArrayBuffer(decodeBase64(b64));
}
function normalizeSignature(signature: string): string {
const trimmed = signature.trim();
if (trimmed.startsWith("sha256=")) {
return trimmed.slice(7);
}
return trimmed;
}
function decodeBase64(input: string): Uint8Array {
try {
const normalized = input.replace(/\s+/g, "");
const binary = atob(normalized);
const bytes = new Uint8Array(binary.length);
for (let i = 0; i < binary.length; i += 1) {
bytes[i] = binary.charCodeAt(i);
}
return bytes;
} catch {
throw new KickWebhookSignatureError(
"Invalid base64 encoding in signature header"
);
}
}
function toArrayBuffer(view: Uint8Array): ArrayBuffer {
const copy = new Uint8Array(view.length);
copy.set(view);
return copy.buffer;
}
function coercePayload(
eventType: string,
eventVersion: string,
payload: Record<string, unknown>
): KickWebhookPayload | null {
if (!eventType) {
return null;
}
const version = (eventVersion || "1") as KickWebhookPayload["eventVersion"];
switch (eventType as KickWebhookEventType | string) {
case "chat.message.sent":
return {
eventType: "chat.message.sent",
eventVersion: version,
...payload,
} as ChatMessageEvent;
case "channel.followed":
return {
eventType: "channel.followed",
eventVersion: version,
...payload,
} as ChannelFollowEvent;
case "channel.subscription.renewal":
return {
eventType: "channel.subscription.renewal",
eventVersion: version,
...payload,
} as SubscriptionRenewalEvent;
case "channel.subscription.gifts":
return {
eventType: "channel.subscription.gifts",
eventVersion: version,
...payload,
} as SubscriptionGiftEvent;
case "channel.subscription.new":
return {
eventType: "channel.subscription.new",
eventVersion: version,
...payload,
} as NewSubscriptionEvent;
case "livestream.status.updated":
return {
eventType: "livestream.status.updated",
eventVersion: version,
...payload,
} as LivestreamStatusUpdatedEvent;
case "kicks.gifted":
return {
eventType: "kicks.gifted",
eventVersion: version,
...payload,
} as KicksGiftedEvent;
default:
return null;
}
}
function isRecord(value: unknown): value is Record<string, unknown> {
return typeof value === "object" && value !== null && !Array.isArray(value);
}
|