RSSHub/lib/middleware/header.ts

59 lines
1.7 KiB
TypeScript

import { getIp } from "@/utils/helpers";
import { MiddlewareHandler } from "hono";
import etagCalculate from "etag";
import logger from "@/utils/logger";
import { config } from "@/config";
const headers: Record<string, string> = {
'Access-Control-Allow-Methods': 'GET',
'Content-Type': 'application/xml; charset=utf-8',
'Cache-Control': `public, max-age=${config.cache.routeExpire}`,
'X-Content-Type-Options': 'nosniff',
};
if (config.nodeName) {
headers['RSSHub-Node'] = config.nodeName;
}
function etagMatches(etag: string, ifNoneMatch: string | null) {
return ifNoneMatch != null && ifNoneMatch.split(/,\s*/).indexOf(etag) > -1
}
const middleware: MiddlewareHandler = async (ctx, next) => {
const ip = getIp(ctx);
logger.info(`${ctx.req.url}, user IP: ${ip}`);
for (const key in headers) {
ctx.header(key, headers[key])
}
ctx.header('Access-Control-Allow-Origin', config.allowOrigin || new URL(ctx.req.url).host);
await next();
if (!ctx.res.body || ctx.res.headers.get('ETag')) {
return;
}
const status = Math.trunc(ctx.res.status / 100);
if (2 !== status) {
return;
}
const res = ctx.res as Response;
const body = await res.clone().text();
const etag = etagCalculate(body.replace(/<lastBuildDate>(.*)<\/lastBuildDate>/, '').replace(/<atom:link(.*)\/>/, ''));
ctx.set('ETag', etag);
const ifNoneMatch = ctx.req.header('If-None-Match') ?? null;
if (etagMatches(etag, ifNoneMatch)) {
ctx.status(304);
ctx.body(null);
} else {
const match = body.match(/<lastBuildDate>(.*)<\/lastBuildDate>/);
if (match) {
ctx.header('Last-Modified', match[1]);
}
}
};
export default middleware;