fix(cloudflare-module): output _headers file to correct directory (#3517)

Author: adamdehaven

src/presets/cloudflare/preset.ts

@@ -60,7 +60,7 @@ const cloudflarePages = defineNitroPreset(
       async compiled(nitro: Nitro) {
         await writeWranglerConfig(nitro, "pages");
         await writeCFRoutes(nitro);
-        await writeCFHeaders(nitro);
+        await writeCFHeaders(nitro, "output");
         await writeCFPagesRedirects(nitro);
       },
     },
@@ -93,7 +93,7 @@ const cloudflarePagesStatic = defineNitroPreset(
         }
       },
       async compiled(nitro: Nitro) {
-        await writeCFHeaders(nitro);
+        await writeCFHeaders(nitro, "output");
         await writeCFPagesRedirects(nitro);
       },
     },
@@ -160,7 +160,7 @@ const cloudflareModule = defineNitroPreset(
       },
       async compiled(nitro: Nitro) {
         await writeWranglerConfig(nitro, "module");
-        await writeCFHeaders(nitro);
+        await writeCFHeaders(nitro, "public");
 
         await writeFile(
           resolve(nitro.options.output.dir, "package.json"),

src/presets/cloudflare/utils.ts

@@ -105,8 +105,16 @@ function comparePaths(a: string, b: string) {
   return a.split("/").length - b.split("/").length || a.localeCompare(b);
 }
 
-export async function writeCFHeaders(nitro: Nitro) {
-  const headersPath = join(nitro.options.output.dir, "_headers");
+export async function writeCFHeaders(
+  nitro: Nitro,
+  outdir: "public" | "output"
+) {
+  const headersPath = join(
+    outdir === "public"
+      ? nitro.options.output.publicDir
+      : nitro.options.output.dir,
+    "_headers"
+  );
   const contents = [];
 
   const rules = Object.entries(nitro.options.routeRules).sort(