import { logger } from './logger.js';
/** Default timeout for favicon fetch requests (10 seconds) */
const FETCH_TIMEOUT_MS = 10000;
/** Maximum favicon file size (1MB) to prevent memory issues */
const MAX_FAVICON_SIZE = 1024 * 1024;
/**
* Fetch with timeout support
* @param url - URL to fetch
* @param timeoutMs - Timeout in milliseconds
* @returns Response object
*/
async function fetchWithTimeout(url: string, timeoutMs: number = FETCH_TIMEOUT_MS): Promise<Response> {
const controller = new AbortController();
const timeoutId = setTimeout(() => controller.abort(), timeoutMs);
try {
const response = await fetch(url, { signal: controller.signal });
return response;
} finally {
clearTimeout(timeoutId);
}
}
/**
* Fetch favicon for a URL with timeout and size limits
* @param url - The URL to fetch favicon for
* @returns Base64 encoded favicon data URL or undefined
*/
export async function fetchFavicon(url: URL): Promise<string | undefined> {
try {
// Try standard favicon.ico location
const faviconUrl = new URL('/favicon.ico', url.origin);
const response = await fetchWithTimeout(faviconUrl.toString());
if (response.ok) {
// Check content length before downloading
const contentLength = response.headers.get('content-length');
if (contentLength && parseInt(contentLength, 10) > MAX_FAVICON_SIZE) {
logger.debug(`[Favicon] Favicon too large: ${contentLength} bytes`);
return undefined;
}
const buffer = await response.arrayBuffer();
if (buffer.byteLength > MAX_FAVICON_SIZE) {
logger.debug(`[Favicon] Favicon too large: ${buffer.byteLength} bytes`);
return undefined;
}
const base64 = Buffer.from(buffer).toString('base64');
const mimeType = response.headers.get('content-type') || 'image/x-icon';
return `data:${mimeType};base64,${base64}`;
}
// Try HTML head meta tags
const pageResponse = await fetchWithTimeout(url.toString());
const html = await pageResponse.text();
// Look for favicon in meta tags
const iconMatch =
html.match(/<link[^>]*?rel=["'](?:shortcut )?icon["'][^>]*?href=["']([^"']+)["'][^>]*>/i) ||
html.match(/<link[^>]*?href=["']([^"']+)["'][^>]*?rel=["'](?:shortcut )?icon["'][^>]*>/i);
if (iconMatch) {
const iconUrl = new URL(iconMatch[1], url.origin);
const iconResponse = await fetchWithTimeout(iconUrl.toString());
if (iconResponse.ok) {
// Check content length before downloading
const contentLength = iconResponse.headers.get('content-length');
if (contentLength && parseInt(contentLength, 10) > MAX_FAVICON_SIZE) {
logger.debug(`[Favicon] Icon too large: ${contentLength} bytes`);
return undefined;
}
const buffer = await iconResponse.arrayBuffer();
if (buffer.byteLength > MAX_FAVICON_SIZE) {
logger.debug(`[Favicon] Icon too large: ${buffer.byteLength} bytes`);
return undefined;
}
const base64 = Buffer.from(buffer).toString('base64');
const mimeType = iconResponse.headers.get('content-type') || 'image/x-icon';
return `data:${mimeType};base64,${base64}`;
}
}
return undefined;
} catch (error) {
// Handle abort errors (timeout) differently
if (error instanceof Error && error.name === 'AbortError') {
logger.debug(`[Favicon] Timeout fetching favicon for ${url.origin}`);
} else {
logger.debug(`[Favicon] Error fetching favicon for ${url.origin}:`, error);
}
return undefined;
}
}
