Qfyilyi

I have a concept called snapshot which basically stores a snapshot of how data looked at a certain period of time. What I'm building is a method that loops through the snapshots for each events, and builds a small hash outlining the ownership over time for a given shareholder.

  def fetch_ownership_over_time(shareholder, captable)



    @shareholder = Shareholder.find(shareholder.id)

    @captable = Captable.find(captable.id)

    @company = @captable.company.id

    @ownership_over_time = 



    @captable.events.collect(&:snapshot).each do |snapshot|

      parsed_snapshot = JSON.parse(snapshot)



      @ownership_over_time.push(parsed_snapshot["event"]["name"])

      @ownership_over_time.push(parsed_snapshot["event"]["date"])



      parsed_snapshot["shareholders"].each do |shareholder|

        if shareholder["id"] == @shareholder.id



          @ownership_over_time.push(shareholder["ownership_percentage"]) 



        end

      end

    end

    return @ownership_over_time

  end

I then call this method in my view which successfully retrieves the correct values however they are not structured in any way:

["Event 1 ", "2018-11-19", "0.666666666666667", "Event 2 ", "2018-11-19", "0.333333333333333", "4th event ", "2018-11-19", "0.315789473684211"]

What I'd like to do now though is construct my hash so that each separate snapshot event contains a name, date and ownership_percentage.

Perhaps something like this:

ownership_over_time = [

    {

    event_name = "Event 1" #parsed_snapshot["event"]["name"]

    event_date = "20180202" #parsed_snapshot["event"]["date"]

    ownership_percentage = 0.37 #shareholder["ownership_percentage"]

    },

    {

    event_name = "Event 2" #parsed_snapshot["event"]["name"]

    event_date = "20180501" #parsed_snapshot["event"]["date"]

    ownership_percentage = 0.60 #shareholder["ownership_percentage"]

    }

]

My challenge though is that the ["event"]["name"] an ["event"]["date"] attributes I need to fetch when looping over my snapshots i.e. the first loop (.each do |snapshot|) whereas I get my ownership_percentage when looping over shareholders - the second loop (.each do |shareholder|).

So my question is - how can I build this hash in "two" places so I can return the hash with the 3 attributes?

Appreciative of guidance/help - thank you!

You have to create a new hash for the object and append that hash to the array of objects you are creating.

  def fetch_ownership_over_time(shareholder, captable)



    @shareholder = Shareholder.find(shareholder.id)

    @captable = Captable.find(captable.id)

    @company = @captable.company.id

    @ownership_over_time = 



    @captable.events.collect(&:snapshot).each do |snapshot|

      parsed_snapshot = JSON.parse(snapshot)

      shareholder = parsed_snapshot['shareholders'].select { |s| s['id'] == @shareholder.id }.first



      local_snapshot = {

        'event_name' => parsed_snapshot['event']['name'],

        'event_date' => parsed_snapshot['event']['date'],

        'ownership_percentage' => shareholder.try(:, "ownership_percentage") || 0

      }



      @ownership_over_time.push local_snapshot

    end

    return @ownership_over_time

  end

Notice that I changed your second loop to a select. As you currently have it, you risk on pushing two percentages if the id is found twice.

EDIT:

Added functionality to use a default value if no shareholder is found.