Early exit from a Kemal route

Is it possible to exit from a Kemal route earlier based on some condition without using halt? For example, can I do something like:

post "/someroute" do |env|
    if not_cond_satisfied
         exit here
    do some processing here. Reaches this part only if cond_satisfied.
  1. I know that one can add an else statement before do some processing.... However, this is a simple example. I would have too many nested if-else statements in what I want to do, and hence would prefer to do this in the manner above if possible.

  2. I know about halt env status_code reason. However, that allows me to only send a string as reason. I would ideally like to send json because that is what I send if everything is successful.

Thank you.

I mean halt is the way to do this. JSON is just a string anyway, why not just return a JSON string via halt?

Something like

halt env, 400, %({"code":400,"message":"Some message"})

Whats the use case here? Some JSON API? If you’re checking for like auth headers or something, it might be better to do this in a handler so that you wouldn’t have to duplicate it within every route.

EDIT: You could also define your own macro like halt that also adds an application/json content type header.

You can use next to exit early from a block.

I am using a server, say uploader to perform file uploads (check a few things and then save the files that are sent to it if checks pass). Another server, say requester will make requests to uploader by sending files to it. I want the uploader to send a json response to the requester about what happened. Example: {type: “error”, msg: “Upload failed because of problem X”} or {type: “error”, msg: “Upload failed because of problem Y”}. I think your string solution should work. I will try it.

Thank you.

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