Rails Csv.new where is this class being called from?

Question

I'm creating my own version of Rayan Bates CSV screencast here...

http://railscasts.com/episodes/396-importing-csv-and-excel

I have this in my model...

 def self.open_spreadsheet(file)
    case File.extname(file.original_filename)
    when ".csv" then Csv.new(file.path, nil, :ignore)
    when ".xls" then Excel.new(file.path, nil, :ignore)
    when ".xlsx" then Excelx.new(file.path, nil, :ignore)
    else raise "Unknown file type: #{file.original_filename}"
    end
  end

...and am getting this error in my app...

 NameError in StudentsController#import

uninitialized constant Student::Csv

Rails.root: /home/wintas/railsApps/t4
Application Trace | Framework Trace | Full Trace

app/models/student.rb:25:in `open_spreadsheet'
app/models/student.rb:13:in `import'
app/controllers/students_controller.rb:12:in `import'

I can't find where the class 'Csv' is initialized, or where it should be coming from. Any help appreciated.

score 2 · Accepted Answer · answered Feb 27 '14 at 19:09

2

I believe that since that Railscast was published, Roo has been updated to namespace Csv, Excel, and Excelx under the Roo namespace. Try this instead:

def self.open_spreadsheet(file)
  case File.extname(file.original_filename)
  when ".csv" then Roo::Csv.new(file.path, nil, :ignore)
  when ".xls" then Roo::Excel.new(file.path, nil, :ignore)
  when ".xlsx" then Roo::Excelx.new(file.path, nil, :ignore)
  else raise "Unknown file type: #{file.original_filename}"
  end
end

answered Feb 27 '14 at 19:09

Dylan Markow

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Thanks Dylan, that worked. But its strange. I am using all the same rails version and gem as Ryan's base app. – Mark Locklear Feb 27 '14 at 19:18
@Lumbee but are you using the same version of the gem? That Railscast used 1.10.1, whereas it's currently at 1.13.2. – Dylan Markow Feb 28 '14 at 01:19
When using Roo::Csv is still getting error, please try to Roo::CSV. I hope this help. – akbarbin Jul 07 '15 at 08:51

score 2 · Answer 2 · answered Aug 07 '14 at 23:18

Newer equivalent of that function using roo 1.13.2 is:

def self.open_spreadsheet(file)
  case File.extname(file.original_filename)
    when ".csv" then Roo::CSV.new(file.path, file_warning: :ignore)
    when ".xls" then Roo::Excel.new(file.path, file_warning: :ignore)
    when ".xlsx" then Roo::Excelx.new(file.path, file_warning: :ignore)
    else raise "Unknown file type: #{file.original_filename}"
  end
end

score 0 · Answer 3 · answered Feb 27 '14 at 19:24

0

In the ruby standard library, csv is all caps: CSV. Does that help?

answered Feb 27 '14 at 19:24

Peter P.

3,221
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`Csv` is a class within the `Roo` gem, different from Ruby's stdlib `CSV` class. – Dylan Markow Feb 28 '14 at 01:19
Yes I realize, but in the Railscast tutorial, it appears, Ryan Bates is using the ruby CSV library to start with, so I thought this might be a source of confusion for the OP. In anycase, you're probably right, its probably a gem version issue necessitating namespacing – Peter P. Feb 28 '14 at 02:05
1

Turns out @PeterP was correct about the capitalization but not for the correct reason. See jesai's answer as that is what fixed it for me. – aarona May 05 '15 at 23:40

score 0 · Answer 4 · answered Aug 30 '15 at 10:23

0

try restarting the server; I had the problem before and restarting the server resolved the issue

answered Aug 30 '15 at 10:23

aweful Brown

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5

Rails Csv.new where is this class being called from?

4 Answers4