fix: match skip prefixes on a path boundary

.changeset/skip-prefix-boundary.md

@@ -0,0 +1,9 @@
+---
+"@dualmark/cloudflare": patch
+"@dualmark/netlify": patch
+"@dualmark/vercel": patch
+---
+
+Match skip prefixes on a path boundary so a page sharing a prefix is not skipped.
+
+The cloudflare, netlify and vercel adapters tested skip prefixes with a bare `startsWith`, so with the default `["/admin", "/api/", "/_"]` a real page like `/administrator` (or `/admins`) matched `/admin` and was silently excluded from content negotiation, its markdown twin, and the Link header. They now use the same boundary-aware check as the deno and fastly adapters: a prefix matches only the exact path or a `prefix/` subpath (a prefix that already ends in `/` still matches by `startsWith`). Asset paths under `/_` remain covered by the extension list.

packages/cloudflare/src/worker.ts

@@ -40,7 +40,12 @@ function shouldSkip(
   extensions: ReadonlyArray<string>,
 ): boolean {
   if (extensions.some((ext) => pathname.endsWith(ext))) return true;
-  return prefixes.some((p) => pathname.startsWith(p));
+  return prefixes.some((p) => {
+    if (pathname === p) return true;
+    if (p.endsWith("/")) return pathname.startsWith(p);
+    // Match on a path boundary so "/admin" does not also skip "/administrator".
+    return pathname.startsWith(p + "/");
+  });
 }
 
 function normalizePath(pathname: string): string {

packages/cloudflare/test/worker.test.ts

@@ -83,6 +83,20 @@ describe("createAEOWorker — markdown serving", () => {
     expect(await res.text()).toBe("# Post 1\n\nBody.");
   });
 
+  it("does not skip a path that merely shares a skip prefix (/administrator)", async () => {
+    const worker = createAEOWorker({
+      upstream: makeUpstream(() => new Response("html", { headers: { "Content-Type": "text/html" } })),
+    });
+    const env: TestEnv = { ASSETS: makeAssets({ "/administrator.md": "# Admin Guide" }) };
+    const req = new Request("https://acme.test/administrator", {
+      headers: { "user-agent": "GPTBot/1.0" },
+    });
+    const res = await worker.fetch(req, env, makeCtx());
+    expect(res.status).toBe(200);
+    expect(res.headers.get("content-type")).toBe("text/markdown; charset=utf-8");
+    expect(await res.text()).toBe("# Admin Guide");
+  });
+
   it("serves markdown when Accept: text/markdown (no bot UA)", async () => {
     const worker = createAEOWorker({
       upstream: makeUpstream(() => new Response("html", { headers: { "Content-Type": "text/html" } })),

packages/netlify/src/worker.ts

@@ -47,7 +47,12 @@ function shouldSkip(
   extensions: ReadonlyArray<string>,
 ): boolean {
   if (extensions.some((ext) => pathname.endsWith(ext))) return true;
-  return prefixes.some((p) => pathname.startsWith(p));
+  return prefixes.some((p) => {
+    if (pathname === p) return true;
+    if (p.endsWith("/")) return pathname.startsWith(p);
+    // Match on a path boundary so "/admin" does not also skip "/administrator".
+    return pathname.startsWith(p + "/");
+  });
 }
 
 function normalizePath(pathname: string): string {

packages/netlify/test/worker.test.ts

@@ -62,6 +62,19 @@ describe("createAEOWorker — markdown serving", () => {
     expect(await res.text()).toBe("# Post 1\n\nBody.");
   });
 
+  it("does not skip a path that merely shares a skip prefix (/administrator)", async () => {
+    const worker = createAEOWorker({
+      assets: makeAssets({ "/administrator.md": "# Admin Guide" }),
+    });
+    const req = new Request("https://acme.test/administrator", {
+      headers: { "user-agent": "GPTBot/1.0" },
+    });
+    const res = await worker(req, makeContext());
+    expect(res.status).toBe(200);
+    expect(res.headers.get("content-type")).toBe("text/markdown; charset=utf-8");
+    expect(await res.text()).toBe("# Admin Guide");
+  });
+
   it("serves markdown when Accept: text/markdown (no bot UA)", async () => {
     const worker = createAEOWorker({ assets });
     const req = new Request("https://acme.test/blog/post-1", {

packages/vercel/src/middleware.ts

@@ -50,7 +50,12 @@ function shouldSkip(
   extensions: ReadonlyArray<string>,
 ): boolean {
   if (extensions.some((ext) => pathname.endsWith(ext))) return true;
-  return prefixes.some((p) => pathname.startsWith(p));
+  return prefixes.some((p) => {
+    if (pathname === p) return true;
+    if (p.endsWith("/")) return pathname.startsWith(p);
+    // Match on a path boundary so "/admin" does not also skip "/administrator".
+    return pathname.startsWith(p + "/");
+  });
 }
 
 function normalizePath(pathname: string): string {

packages/vercel/test/middleware.test.ts

@@ -53,6 +53,22 @@ describe("createAEOMiddleware — markdown serving", () => {
     expect(await res.text()).toBe("# Post 1\n\nBody.");
   });
 
+  it("does not skip a path that merely shares a skip prefix (/administrator)", async () => {
+    const middleware = createAEOMiddleware({
+      upstream: makeUpstream(
+        () => new Response("html", { headers: { "Content-Type": "text/html" } }),
+      ),
+      fetchAsset: makeAssets({ "/administrator.md": "# Admin Guide" }),
+    });
+    const req = new Request("https://acme.test/administrator", {
+      headers: { "user-agent": "GPTBot/1.0" },
+    });
+    const res = await middleware(req, makeCtx());
+    expect(res.status).toBe(200);
+    expect(res.headers.get("content-type")).toBe("text/markdown; charset=utf-8");
+    expect(await res.text()).toBe("# Admin Guide");
+  });
+
   it("serves markdown when Accept: text/markdown (no bot UA)", async () => {
     const middleware = createAEOMiddleware({
       upstream: makeUpstream(