ROR import csv file no method error

Question

the error:

NoMethodError (undefined method `read' for nil:NilClass):
app/controllers/imports_controller.rb:5:in `upload'

I reworked my csv upload routine from my earlier question Adding CSV Import to a ROR application

I had found a question that was asked several years ago that seemed similar to what I wanted but some of the code was in Spanish Ruby on Rails - Import CSV file

imports_controller:

class ImportsController < ApplicationController    

def upload
logger.info "File loaded"
infile = params[:dump][:infile].read
n, errors = 0, []
@archive = []
CSV.parse(infile) do |row|
  n += 1
  # SKIP: header i.e. first row OR blank row
  next if n == 1 or row.join.blank?
  imports = Imports.build_from_csv(row)
  if imports.valid?
    imports.save
    @archive << row
  else
    errors << row
  end
  end
logger.info errors
flash[:success] = "The CSV imported successfully" 

respond_to do |format|
  format.html # index.html.erb
  format.json { render :json => @archive }
    end
 end 
end

*note that there seems to be extra end but until I added them I was getting an application error

models/imports.rb:

class Imports < ActiveRecord::Base

def self.build_from_csv(row)
 #last_level = (row[5].downcase == "yes"
     imports = Imports.new(:imports => "#{row[0]}}",
                            :cart_items => "#{row[1].titlesize}",
                            :cart_items_quantity => "#{row[2].titlesize}",
                            :cart_items_price => "#{row[3].titlesize}",
                            :cart_items_description => "#{row[4].titlesize}",
                            :cart_items_upc => "#{row[5].titlesize}",
                            :cart_items_sku => "#{row[6].titlesize}")
                           # :last_level=> last_level)
return imports
end
end

and here is the form call that I use to upload the csv:

<h3>Import CSV Order</h3>                                
                 <% form_for :dump, :url=>{:controller=>"imports", :action=>"upload"}, :html => { :multipart => true } do |f| -%>
                     <table">
                       <tr>
                         <td>
                          <label for="dump_file">
                            Select a CSV File :
                          </label>
                         </td>
                         <td >
                           <%= f.file_field :infile -%>
                         </td>
                       </tr>
                       <tr>
                         <td colspan='2'>
                           <%= submit_tag 'Submit' -%>
                         </td>
                       </tr>
                     </table>

So any thoughts on the no method error would be much appreciated. As you can tell I am new to Ruby and this was an inherited app so any help is most welcome! thanks

Answer 1

Yep, it's nil. It's not where you are expecting it to be. Your form_for :dump semantically constructs a form for object "dump". It is represented by a hash in params by the corresponding key. So, actually, that parameter is over there:

params[:dump][:infile]