Import CSV Data in a Rails App with ActiveAdmin

Question

i want to upload CSV files through the activeadmin panel.

on the index page from the resource "product" i want a button next to the "new product" button with "import csv file".

i dont know where to start. in the documentation is something about collection_action, but with the code below i have no link at the top.

ActiveAdmin.register Post do
    collection_action :import_csv, :method => :post do
      # Do some CSV importing work here...
      redirect_to :action => :index, :notice => "CSV imported successfully!"
    end
  end

anyone here who use activeadmin and can import csv data?

Answer 1

Continuing from Thomas Watsons great start to the answer which helped me get my bearings before figuring the rest of it out.

The code blow allows not just CSV upload for the example Posts model but for any subsequent models thereafter. all you need to do is copy the action_item ands both collection_actions from the example into any other ActiveAdmin.register block and the functionality will be the same. hope this helps.

app/admin/posts.rb

ActiveAdmin.register Post do
  action_item :only => :index do
    link_to 'Upload CSV', :action => 'upload_csv'
  end

  collection_action :upload_csv do
    render "admin/csv/upload_csv"
  end

  collection_action :import_csv, :method => :post do
    CsvDb.convert_save("post", params[:dump][:file])
    redirect_to :action => :index, :notice => "CSV imported successfully!"
  end

end

app/models/csv_db.rb

require 'csv'
class CsvDb
  class << self
    def convert_save(model_name, csv_data)
      csv_file = csv_data.read
      CSV.parse(csv_file) do |row|
        target_model = model_name.classify.constantize
        new_object = target_model.new
        column_iterator = -1
        target_model.column_names.each do |key|
          column_iterator += 1
          unless key == "ID"
            value = row[column_iterator]
            new_object.send "#{key}=", value
          end
        end
        new_object.save
      end
    end
  end
end

note: this example does a check to see whether or not the first column is an ID column, it then skips that column as rails will assign an ID to the new object (see example CSV below for reference)

app/views/admin/csv/upload_csv.html.haml

= form_for :dump, :url=>{:action=>"import_csv"}, :html => { :multipart => true } do |f|
  %table
    %tr
      %td
        %label{:for => "dump_file"}
          Select a CSV File :
      %td
        = f.file_field :file
    %tr
      %td
        = submit_tag 'Submit'

app/public/example.csv

"1","TITLE EXAMPLE","MESSAGE EXAMPLE","POSTED AT DATETIME"
"2","TITLE EXAMPLE","MESSAGE EXAMPLE","POSTED AT DATETIME"
"3","TITLE EXAMPLE","MESSAGE EXAMPLE","POSTED AT DATETIME"
"4","TITLE EXAMPLE","MESSAGE EXAMPLE","POSTED AT DATETIME"
"5","TITLE EXAMPLE","MESSAGE EXAMPLE","POSTED AT DATETIME"

note: quotations not always needed