File is downloaded instead of being displayed in the browser

Question

I have created a brand new app from the luminus app template using lein new luminus my-app +postgres +auth +cljs +swagger. In the generated file src/clj/my_app/routes/home.clj the following compojure route is created:

(GET "/docs" [] (response/ok (-> "docs/docs.md" io/resource slurp)))

When I try to access localhost:3000/docs the file is simply downloaded instead of displayed in the browser. It happens both with Chrome and Safari.

It seems related to ring.util.http-response/ok since I can reproduce the behavior using this route too:

(GET "/hi" [] (response/ok "hi")).

A file "hi" is then downloaded with file content "hi".

Any ideas on what's causing this?

Answer 1

Your response handler doesn't set Content-Type for your response body.

You can do it using ring.util.http-response/content-type:

(GET "/hi" [] (-> "hi"
                  (response/ok)
                  (response/content-type "text/plain")))

You can also wrap your handler in ring.middleware.content-type/wrap-content-type so the headers are "guessed" based on the file extension from the URI.