Custom static file handling: handle_response_inner is private, leading to excessive code duplication

[NCura]

Hi! I'm using Axum with Leptos and wanted to customize how static files are served, specifically to add a Cache-Control header.

I saw that I could replace:

.fallback(leptos_axum::file_and_error_handler::<AppState, _>(shell))

with my own custom version. After checking the source, I found this helpful comment in file_and_error_handler:

A reasonable handler for serving static files (like JS/WASM/CSS) and 404 errors.
This is provided as a convenience, but is a fairly simple function. If you need to adapt it, simply reuse the source code of this function in your own application.

That’s exactly what I needed. I wanted to tweak the get_static_file function to include a CACHE_CONTROL header, so I:

1. Created a fileserv.rs file.

2. Copy-pasted the implementations of:

   • file_and_error_handler
   • file_and_error_handler_with_context
   • get_static_file

However, I quickly hit a snag, file_and_error_handler_with_context calls a private function: handle_response_inner. That meant I also had to copy that function, and now I’m up to 241 lines of mostly unchanged code just to make a minor adjustment to one function.

It works well, but I’m wondering:

• Is there a specific reason handle_response_inner is private?
• Would you accept a PR making it public so customization like mine requires less duplication?
• Or is the current expectation to copy-paste all relevant source if a change is needed?

Thanks for your time!

[benwis]

I suspect it’s private mostly because we haven’t really decided that’s a public api. In a broad sense it has grown to do more over time. Happy to accept a PR to make it public if it’s helpful to you

…

On Tue, May 20, 2025, at 11:41 AM, Nicolas Cura wrote: *NCura* created an issue (leptos-rs/leptos#3996) <#3996> Hi! I'm using Axum with Leptos and wanted to customize how static files are served, specifically to add a `Cache-Control` header. I saw that I could replace: .fallback(leptos_axum::file_and_error_handler::<AppState, _>(shell)) with my own custom version. After checking the source, I found this helpful comment in `file_and_error_handler`: > > A reasonable handler for serving static files (like JS/WASM/CSS) and 404 errors. > This is provided as a convenience, but is a fairly simple function. If you need to adapt it, simply reuse the source code of this function in your own application. > That’s exactly what I needed. I wanted to tweak the `get_static_file` function to include a `CACHE_CONTROL` header, so I: 1. Created a `fileserv.rs` file. 2. Copy-pasted the implementations of: • `file_and_error_handler` • `file_and_error_handler_with_context` • `get_static_file` However, I quickly hit a snag, `file_and_error_handler_with_context` calls a *private* function: `handle_response_inner`. That meant I also had to copy that function, and now I’m up to 241 lines of mostly unchanged code just to make a minor adjustment to one function. It works well, but I’m wondering: • Is there a specific reason `handle_response_inner` is private? • Would you accept a PR making it public so customization like mine requires less duplication? • Or is the current expectation to copy-paste all relevant source if a change is needed? Thanks for your time! — Reply to this email directly, view it on GitHub <#3996>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABVBTCOLDU62O5VW4JDLUQT27L2FXAVCNFSM6AAAAAB5P6SW2OVHI2DSMVQWIX3LMV43ASLTON2WKOZTGA3TMMZXGY4TGNA>. You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>