Rails 5.1 .：从关联中获取每个日期时间间隔的记录

Question

I have Model named Task with method dates which gives me this output (it can be different and multiple DateTime intervals):

[{:from=>2017-09-04 00:00:00 +0300, :to=>2017-09-04 05:59:59 +0300},
 {:from=>2017-09-05 12:00:00 +0300, :to=>2017-09-05 19:59:59 +0300}

then in same Model there is another method inventory , where for each task I want to get corresponding Inventory model records.

At the moment I'm trying to do something like this:

self.inventories.where(date: self.from..self.to)

This does not work, because from and to comes from data structure above and there are no such columns in my DB. I've set appropriate association in my model and I can do self.inventories .

Is there a way to do Rails query in order to grab matching records for each of my dates intervals, please? Thank you.

Answer 1

if your asking how to access data inside an array, you can loop through each data.

def self.dates
  #generate intervals as array of hashes
end

def self.inventories
  [].tap do |inventories|
    dates.each do |date|
      from = date[:from]
      to = date[:to]
      inventories << self.inventories.where(date: from..to)
    end
  end
end

and ensure to use #flatten since it would be nested in arrays

inventories.flatten

hope this helps