How do you set content type while still encoding?

[kanwei]

Library Version(s)

alpha-23: I see that BREAKING: Don't encode response :body if Content-Type header is set.

Problem

We have an endpoint that returns a CSV as a stream:

{:headers {"Content-Type" "text/csv"}
         :body    (ring-io/piped-input-stream
                    (fn [ostream]
                      (let [^java.io.Writer w (clojure.java.io/make-writer ostream {})]
                        (data-csv/write-csv w (util/map->csv-lazily records))
                        (.flush w))))}

This now returns nothing. How are we now supposed to add the content-type but still getting through the encoding stack?

[ikitommi]

How did the data get encoded earlier? Do you have a csv-format for Muuntaja?

[kanwei]

I just use this in the middleware:

             (muuntaja/wrap-params)
             (muuntaja/wrap-format)

It seems to coerce the piped-input-stream to an actual output. In alpha-23 no data is returned at all.

[ikitommi]

That muuntaja change shoudn't affect it. With default configuration, Muuntaja doesn't touch the body if it's a stream, the Streaming of InputStream is handled by the Ring Adapter.

So I think that the problem is somewhere else. Do you have :return or :responses defined for that route? The same code works with the previous version?

[kanwei]

You're right, I can no longer reproduce this.