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
|
export interface Env {
ASSETS: Fetcher; // static assets binding
DOCS_BUILD_SHA: string; // injected at deploy
DOCS_ENV: "production" | "canary";
}
export type CacheClass = "page" | "asset";
export function classifyPath(path: string): CacheClass {
if (path.endsWith(".pdf") || path.includes("/_static/")) return "asset";
return "page"; // HTML, versions.json, sitemaps, robots/llms, pagefind index
}
export function cacheHeaderFor(cls: CacheClass): string {
return cls === "asset"
? "public, max-age=300, s-maxage=600, must-revalidate"
: "public, max-age=0, s-maxage=300, must-revalidate";
}
export function withDocsHeaders(
resp: Response,
path: string,
env: Pick<Env, "DOCS_BUILD_SHA" | "DOCS_ENV">,
): Response {
const out = new Response(resp.body, resp);
out.headers.set("X-Docs-Build", env.DOCS_BUILD_SHA);
out.headers.set(
"Cache-Control",
// Error responses (4xx/5xx) must never carry the page/asset cache class — a
// cached 404 would poison the edge for the full s-maxage window.
env.DOCS_ENV === "canary" || out.status >= 400
? "no-store"
: cacheHeaderFor(classifyPath(path)),
);
return out;
}
export default {
async fetch(request: Request, env: Env): Promise<Response> {
const url = new URL(request.url);
const resp = await env.ASSETS.fetch(request);
return withDocsHeaders(resp, url.pathname, env);
},
} satisfies ExportedHandler<Env>;
|
