Mark different routes as "API routes"

[ivanpetrushev]

Feature request

Is your feature request related to a problem? Please describe.

We have to proxy several routes to a 3rd party service like in this example: #14057 (comment)
This is working only in api routes and in Next.js api routes reside only in pages/api/ directory.
We need paths other than http://domain.com/api/ to be server as API routes.

Describe the solution you'd like

Probably config list in next.config.js containing a list of directories in pages/ that should be interpreted as API routes?
Probably HOC that can be used like:

import {withAsApiRoute} from "next-api-route";
...
export withAsApiRoute(Component);

I am open to other alternatives as well.

Describe alternatives you've considered

Maybe we can use rewrites to change the API routes to desired paths, BUT - docs state rewrites are available only in Node.js environment and we are targeting serverless build.

Thanks.

[timneutkens]

Duplicate of #13344