From 3b8ac70b7829508bbb929ac9718c14131c666d8c Mon Sep 17 00:00:00 2001
From: filzrev <103790468+filzrev@users.noreply.github.com>
Date: Tue, 11 Nov 2025 09:48:55 +0900
Subject: [PATCH] chore: add cache-control response header

---
 src/Docfx.App/RunServe.cs | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/Docfx.App/RunServe.cs b/src/Docfx.App/RunServe.cs
index fa14f8d5135..5ef7a3c8a8d 100644
--- a/src/Docfx.App/RunServe.cs
+++ b/src/Docfx.App/RunServe.cs
@@ -89,6 +89,17 @@ public static IApplicationBuilder UseServe(this WebApplication app, string folde
 
         // Fix the issue that .JSON file is 404 when running docfx serve
         fileServerOptions.StaticFileOptions.ServeUnknownFileTypes = true;
+
+        // Set `Cache-Control` response header. (To avoid browser's default heuristic cache)
+        fileServerOptions.StaticFileOptions.OnPrepareResponse = ctx =>
+        {
+            var headers = ctx.Context.Response.GetTypedHeaders();
+            headers.CacheControl = new Microsoft.Net.Http.Headers.CacheControlHeaderValue
+            {
+                MaxAge = TimeSpan.FromSeconds(60),
+            };
+        };
+
         return app.UseFileServer(fileServerOptions);
     }