Content-type not set when function returning a domain representing media type is requested with Accept "*/*" header

[mkleczek]

Environment

• PostgreSQL version: 16
• PostgREST version: 12.0.2
• Operating system: Windows

Description of issue

I have the following function:

CREATE DOMAIN "text/javascript" AS text;
CREATE OR REPLACE FUNCTION "module.js"() RETURNS "text/javascript"...

When requested by a browser from:

<script type="module" src="/rpc/module.js"></script>

returned response Content-Type is application/json

It seems the browser is setting Accept header to */* and PostgREST does not set proper content type in this case.
As a workaround it is necessary to explicitly set content type in the function using current_setting.

[steve-chavez]

This needs the any handler as mentioned on #3387 (comment)

[wolfgangwalther]

Sorry, but that's still a bug. The function definition clearly tells us that this function is only ever going to return text/javascript, so we should never choose application/json when the header is */*.