Fix: Export collections CSVs with non-ASCII chars (#907)

This commit monkey-patches `CSV.generate` to support non-ASCII locales,
following what Ruby did in ruby/csv#63

Fixes #902

Author: matiasgarciaisaia

app/models/collection/csv_concern.rb

@@ -1,3 +1,24 @@
+class CSV
+  # monkey-patch CSV.generate to support non-ASCII locales
+  # see ruby/csv#63 ( https://github.com/ruby/csv/pull/63/files )
+  def self.generate(*args)
+    # add a default empty String, if none was given
+    if args.first.is_a? String
+      io = StringIO.new(args.shift)
+      io.seek(0, IO::SEEK_END)
+      args.unshift(io)
+    else
+      encoding = args[-1][:encoding] if args.last.is_a?(Hash)
+      str      = +""
+      str.force_encoding(encoding) if encoding
+      args.unshift(str)
+    end
+    csv = new(*args)  # wrap
+    yield csv         # yield for appending
+    csv.string        # return final String
+  end
+end
+
 module Collection::CsvConcern
   extend ActiveSupport::Concern
 

spec/controllers/api/collections_controller_spec.rb

@@ -211,17 +211,20 @@
     end
 
     describe "GET CSV collection" do
+      let!(:site3) {collection.sites.make :name => "किसी जगह", properties: { hierarchy.es_code => 'bro' } }
+
       before(:each) do
         get :show, id: collection.id, format: 'csv'
       end
 
       it { expect(response).to be_success }
 
-      it "should return CSV" do
+      it "should return CSV with non-ASCII values" do
         csv =  CSV.parse response.body
-        expect(csv.length).to eq(3)
+        expect(csv.length).to eq(4)
 
         expect(csv[0]).to eq(['resmap-id', 'name', 'lat', 'long', text.code, numeric.code, yes_no.code, select_one.code, select_many.code, hierarchy.code,"#{hierarchy.code}-1", "#{hierarchy.code}-2", site_ref.code, date.code, director.code, 'last updated'])
+        expect(csv).to include [site3.id.to_s, site3.name, site3.lat.to_s, site3.lng.to_s, "", "", "no", "", "", "bro", "Dad", "Bro", "", "", "", site3.updated_at.to_datetime.rfc822]
         expect(csv).to include [site2.id.to_s, site2.name, site2.lat.to_s, site2.lng.to_s, "", "", "no", "", "", "bro", "Dad", "Bro", "", "", "", site2.updated_at.to_datetime.rfc822]
         expect(csv).to include [site.id.to_s, site.name, site.lat.to_s, site.lng.to_s, site.properties[text.es_code], site.properties[numeric.es_code].to_s, 'yes', 'one', 'one, two', 'dad', 'Dad', '', site2.id.to_s, '10/24/2012', user.email, site.updated_at.to_datetime.rfc822]
       end