Resource handler: serve index file without a redirect

[philipmw]

I am using ring's resource handler (ring/create-resource-handler) to serve a Vite application. Vite builds the application as index.html and other files in the same distribution directory. I rely on the resource handler's support for index files to serve this application. However, the resource handler's index files support doesn't work quite like I expect or would like.

When I request /, this handler responds with an HTTP 302 redirect to /index.html. This results in an undesired customer-visible URL. I want index.html to be an implementation detail, and for the resource handler to serve the content of index.html in response to GET / without a redirect. This would be consistent with how Apache httpd's mod_dir works; see default for DirectoryIndexRedirect directive.

Can you suggest how I can achieve the desired behavior of serving index.html transparently on GET /?

Some options I see:

1. Create a custom route for just /index.html that serves my file directly, with the existing resource handler as a fallback for other routes. I imagine then I'd need to disable conflict resolution, which doesn't sound good.
2. Add a configuration parameter to the ring resource handler to support the equivalent of apache httpd's DirectoryIndexRedirect options. Do you think this would be a good idea?

[opqdonut]

For option 1, you don't need to disable conflict resolution. You'll just have a handler set up for the path "/", and a default handler after that.

For option 2, a PR is welcome. I think it's a reasonable feature.

[philipmw]

I went with option 1 for now. Documenting it here to help others, or if anyone has any suggestions for improving it:

My original ring handler definition (template from kit-clj):

(ring/ring-handler
  (router)
  (ring/routes
    (ring/redirect-trailing-slash-handler)
    (ring/create-resource-handler {:path "/"})
...))

I created a new handler:

(def index-filename "index.html")

(defn index-handler [{:keys [uri]}]
  (if (= uri "/")
    (ring-response/content-type
      (ring-response/resource-response index-filename {:root "public"})
      (mime-type/ext-mime-type index-filename))))

and plugged it into the router:

(ring/ring-handler
  (router)
  (ring/routes
    (ring/redirect-trailing-slash-handler)
    index-handler
    (ring/create-resource-handler {:path "/"})
...))

I ran into a curious problem with the mime-type. My original code was simply returning (ring-response/resource-response index-filename {:root "public"}), and it was working for me locally. Locally it was sending the Content-Type: text/html header, but once I deployed it to production, the webapp was sending Content-Type: application/octet-stream. I don't know why the discrepancy.

Once I wrapped resource-response in the content-type call, it worked well both locally and in production.