Merge pull request #10 from mfamilia/master

Allow configuration of alphabet for hashids

README.md

@@ -46,6 +46,9 @@ easily reverse engineer your ids, create an initializer and:
 Hashid::Rails.configure do |config|
   config.secret = 'my secret'
   config.length = 6
+  # config.alphabet is optional, hashids provides a default
+  # alphabet that consists of all characters [a-zA-Z0-9]
+  config.alphabet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
 end
 ```
 

lib/hashid/rails.rb

@@ -38,7 +38,12 @@ module ClassMethods
       def hashids
         secret = Hashid::Rails.configuration.secret
         length = Hashid::Rails.configuration.length
-        Hashids.new("#{table_name}#{secret}", length)
+        alphabet = Hashid::Rails.configuration.alphabet
+
+        arguments = ["#{table_name}#{secret}", length]
+        arguments << alphabet if alphabet.present?
+
+        Hashids.new(*arguments)
       end
 
       def encode_id(id)
@@ -61,11 +66,12 @@ def model_reload?
     end
 
     class Configuration
-      attr_accessor :secret, :length
+      attr_accessor :secret, :length, :alphabet
 
       def initialize
         @secret = ''
         @length = 6
+        @alphabet = nil
       end
     end
 

spec/hashid/rails_spec.rb

@@ -56,6 +56,35 @@
       end
     end
 
+    describe 'alphabet' do
+      let(:expected_alphabet) { 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' }
+      let(:config) { Hashid::Rails.configuration }
+
+      context 'with custom alphabet' do
+        before :each do
+          Hashid::Rails.configure do |config|
+            config.alphabet = expected_alphabet
+          end
+        end
+
+        it 'initializes hashid correctly'  do
+          expect(Hashids).to receive(:new)
+                         .with('models', config.length, expected_alphabet)
+
+          Model.hashids
+        end
+      end
+
+      context 'with no custom alphabet' do
+        it 'initializes hashid correctly' do
+          expect(Hashids).to receive(:new)
+                         .with('models', config.length)
+
+          Model.hashids
+        end
+      end
+    end
+
   end
 
   describe '#reload' do