Return Attribute of Class Instance - ruby-on-rails

Question

Basically I have a table output on a page, base view. The headers (milestones) are dynamically integrated by passing the Milestones class and iterating through each with an .each do. The table rows are then initially generated by doing the same thing, pulling in client, trade, and units, into the first three columns. The rest of the columns should be dates (class entry attribute due) that are calculated by a lookup of sorts using the client and trade attributes accessible by the loop, and the milestone ID accessible by an array created when dynamically generating them for the headers. This all works correctly as it should, and the table generates fine.. however the dates are output as #<Entry:0x000000056faa90> and so on.
Now I have come across this problem before, and basically the fix was to add a class definition and tell it to return what I assume to be the attribute of that instance. For example:
class Client < ActiveRecord::Base
validates :id, presence:true
validates :client, presence:true
def name
return self.client
end
end
And this works great, but only for how I access the client. Unfortunately I am accessing entry.due differently. Here are my relevant bits of code.
base_controller.rb
class BaseController < ApplicationController
def index
#trades = Trade.all
#milestones = Milestone.all
##entries = Entry.all #Didn't seem relevant to how I am trying to access the information.
end
end
entry.rb
class Entry < ActiveRecord::Base
belongs_to :client
belongs_to :trade
belongs_to :milestone
validates :client, presence:true
validates :trade, presence:true
validates :milestone, presence:true
validates :due, presence:true
# Some of my trial and error; all to no avail.
def due
return self.due
end
def self.due
return self.due
end
def pickDue(c,t,m)
ret = self.select("date_format(due, '%m/%d/%Y')").where("client_id=? AND trade_id=? AND milestone_id=?", c, t, m).first
return ret
end
end
base > index.html.erb
<table>
<thead>
<tr class="sort">
<th>Client</th>
<th>Trade</th>
<th>Units</th>
<%
ms = []
#milestones.each do |milestone|
ms.push(milestone)
%>
<th><%= milestone.name %></th>
<% end %>
</tr>
</thead>
<tbody>
<% #trades.order("entered").last(10).each do |trade| %>
<tr>
<td><%= trade.client.name %></td>
<td><%= trade.name %></td>
<td><%= trade.units %></td>
<% ms.each do |msr| %>
<td>
<%= Entry.select("date_format(due, '%m/%d/%Y')").where("client_id=? AND trade_id=? AND milestone_id=?", trade.client, trade, msr).first %>
<%#= Entry.pickDue(trade.client, trade, msr) %>
</td>
<% end %>
</tr>
<% end %>
</tbody>
</table>
With this approach, I can load the page error-free, but instead of showing dates, I am shown objects like #<Entry:0x000000056faa90>.
If I add .due to the end of the selector:
<%= Entry.select("date_format(due, '%m/%d/%Y')").where("client_id=? AND trade_id=? AND milestone_id=?", trade.client, trade, msr).first.due %>
# undefined method `due' for nil:NilClass
If I add .due after anything else:
<%= Entry.due.select("date_format(due, '%m/%d/%Y')").where("client_id=? AND trade_id=? AND milestone_id=?", trade.client, trade, msr).first %>
<%= Entry.select("date_format(due, '%m/%d/%Y')").due.where("client_id=? AND trade_id=? AND milestone_id=?", trade.client, trade, msr).first %>
<%= Entry.select("date_format(due, '%m/%d/%Y')").where("client_id=? AND trade_id=? AND milestone_id=?", trade.client, trade, msr).due.first %>
# stack level too deep
I have tried dozens of different methods acquired through several days of looking into this with no luck. Besides the current situation where it outputs objects instead of the object attribute, the next closest I've come I think is when I got an error saying it could not find the due method for an ActiveRecord object, but I don't remember how got to that error.
I would really appreciate any input.

Answer 1

If I understand correctly, I would get rid of that trial and error code in your model, and then in your view you can just call this:
Entry.where(client: trade.client, milestone: msr, trade: trade).pluck(:due)
This goes inside your milestone loop in your view, like this:
<% ms.each do |msr| %>
<td>
<%= Entry.where(client: trade.client, milestone: msr, trade: trade).pluck(:due).first %>
</td>
<% end %>
Pluck returns an array of values from the columns you specify (see the relevant section of the RailsGuide, so note that the .first method is the Array#first method, not the ActiveQuery#first method. You could even make a query that passes in all of the milestones at once instead of running a query for each milestone, thereby preventing an N+1 query situation.
That would be:
<% Entry.where(client: trade.client, trade: trade, milestone: ms).pluck(:due).each do |entry_due_date| %>
<td>
<%= entry_due_date %>
</td>
<% end %>
Lastly, while I gave you the code for the SQL query in the view, it is generally considered a bad practice in Rails to write SQL queries in your view, and you should probably make this into a method in your Entry model.

Answer 2

I think you might be looking for attributes method.
entry = Entry.new
entry.attributes #=> returns a hash of key-value attribute pairs