Optional query parameters

[pjmartorell]

Hi, I have a question regarding optional query parameters. I have the following routes defined:

Cuba.define do
  on get do
    on 'movies' do
      on param("genre"), param("offset"), param("limit") do |genre, offset, limit|
        ...
      end
    end
  end
end

But this route only matches when exactly all query params are passed and I would like this route to match even if none are passed or just some. I mean, make these parameters are completely optional. Is there any way to achieve that in a simple way instead of using req.env["rack.request.query_hash"] directly?

Thanks

[soveran]

Maybe you can try something like this?

on param("genre") || param("offset") || param("limit") do |genre, offset, limit|
  ...
end

Another idea would be to use default values (the second parameter to the param matcher), so you can do something like this:

on param("genre", "all") || param("offset", "0") do |genre, offset|
  ...
end

Or a combination of those ideas. Let me know if it works for your use case.

[pjmartorell]

Thanks! I don't know I didn't came up with this solution, both suggestions were very helpful :)

[pjmartorell]

Oops, I noticed that because of the OR clause, whenparam("genre") is present, the rest (offset and limit) are not being evaluated resulting in nil values instead of the passed value or the default value.

[soveran]

My solutions were terrible! But at least the second one can be fixed:

on param("genre", "all"), param("offset", "0") do |genre, offset|
  ...
end

In the original, I intended to use , when passing default values, but I left the ||. The first example should never work.

[pjmartorell]

Thanks for the fast reply! If I'm right, this makes the offset param mandatory, but I would like it to be optional. Anyway I'm considering moving the logic to set default values to another place rather than handling it in the matchers.

[pjmartorell]

Sorry, you were right, it matches the route and sets the default value if it's the query param is not passed. Thanks!