SmarterCSV and resque results in undefined method close

Question

I am trying to use Resque and SmarterCSV but keep seeing the same error:

undefined method 'close' for nil:NilClass

in my resque logs. I'm not sure why it's happening. I've done some digging and people who have seen this found it has to do with a file location being wrong, but I'm simply passing the file as a param, it's not saved anywhere.

My Form:

<%= form_tag check_upload_file_path, multipart: true do %>
    <%= file_field_tag :file %>
    <%= select_tag 'location', options_from_collection_for_select(Location.real, 'id', 'name'), include_blank: true %>
    <br>
    <%= submit_tag "Preview", class: "btn btn-awaken btn-sm approve-me", name: 'preview' %>
<% end %>

My Controller:

def check_upload_file
    Resque.enqueue(AddClientsFromScale, params[:file], params[:location])
    redirect_to bulk_uploads_path
end

My worker:

class AddClientsFromScale
    @queue = :validate_file

    puts "adding clients from scale..."

    def self.perform(file, location_id)
        p file, location_id
        WeighIn.check_file(file, location_id)
    end
end

My model:

class WeighIn < ActiveRecord::Base
    @hash_for_new_clients = {
        ' ID'                           => 'scale_id',
        'Full Name'                     => 'name',
    }

    def self.check_file(file, location_id)
        options = {:key_mapping => @hash_for_new_clients, :strings_as_keys => true, :keep_original_headers => true, :remove_unmapped_keys => true}

        # prints the file and contents properly
        p "file: ", file["tempfile"] 

        SmarterCSV.process(file, options) do |row|
            p row
        end
    end
end

Anyone know what's going on?

Answer 1

The issue is that the file variable is a hash containing more data than just the file itself. The clue is where you print it using file["tempfile"] . That's what you need to plug into SmarterCSV, because that is what references the actual file you're trying to process.

SmarterCSV.process(file["tempfile"], options) do |row|

In my case I had an additional file encoding issue where I received this error from SmarterCSV:

WARNING: you are trying to process UTF-8 input, but did not open the input with "b:utf-8" option. See README file "NOTES about File Encodings".

This was what did it for me in the end:

f = File.open(file["tempfile"], "r:bom|utf-8")
SmarterCSV.process(f, options) do |row|
    ...