从哈希中删除空值

Question

I have recive such params from request

params[:search] = {"user_id_in"=>[""], "status_in"=>[""], "priority_in"=>["", "8"]}

I need to clear it, because metasearch gem works incorrect with it

params[:search] = {"priority_in"=>["8"]}

Answer 1

I have a solution with double select usage:

params[:search] = {"user_id_in"=>[""], "status_in"=>[""], "priority_in"=>["", "8"]}

params[:search].select! do |k, v|
  v.select! do |vv|
    !vv.empty?
  end
  v.length > 0
end

Answer 2

Functional approach (except, of course, for the last assign since you asked for a in-place update):

pairs = params[:search].map { |k, vs| [k, vs.reject(&:blank?)] }
params[:search] = Hash[pairs.select { |k, vs| vs.present? }]