Look for existing S3 bucket before creating a new one (#15)

lib/shutterbug/storage/s3_storage.rb

@@ -26,6 +26,10 @@ def self.create_bin
           :public => true)
       end
 
+      def self.lookup_bin
+        self.connection.directories.get(Configuration.instance.s3_bin) || self.create_bin
+      end
+
       def self.s3_bin
         @s3_bin ||= self.create_bin
       end

spec/shutterbug/s3_storage_spec.rb

@@ -2,11 +2,51 @@
 require 'fog'
 
 describe Shutterbug::Storage::S3Storage do
-  let(:mock_write_result) { mock(:public_url => "http://amazon.cloud/url.png")}
+  let(:s3_bin)  { nil }
+  let(:storage) { Shutterbug::Storage::S3Storage}
+  let(:mock_write_result) { double(:public_url => "http://amazon.cloud/url.png")}
   before(:each) do
-    Shutterbug::Storage::S3Storage.stub!(:write => mock_write_result)
+    storage.stub(:write => mock_write_result)
   end
 
   it_behaves_like "a storage provider" do
   end
+
+  describe "some class methods" do
+    before(:each) do
+      Fog.mock!
+    end
+    describe "s3_bin" do
+      subject do
+        storage
+      end
+      describe "when the bin is already configured" do
+        let(:fake_bin) { "xyzzy" }
+        it "should not call #lookup_bin or #create_bin" do
+          subject.instance_variable_set(:@s3_bin, fake_bin)
+          subject.should_not_receive(:lookup_bin)
+          subject.should_not_receive(:create_bin)
+          subject.s3_bin.should eq fake_bin
+          # reset
+          subject.instance_variable_set(:@s3_bin,nil)
+        end
+      end
+      describe "when the bin can't be found" do
+        let(:fake_bin) { "xyzzy" }
+        it "should call #create_bin" do
+          subject.stub_chain(:connection,:directories,:get).and_return(nil)
+          subject.should_receive(:create_bin).and_return(fake_bin)
+          subject.s3_bin.should eq fake_bin
+        end
+      end
+      describe "when the bin exists" do
+        let(:fake_bin) { "xyzzy" }
+        it "should not call #create_bin" do
+          subject.stub_chain(:connection,:directories,:get).and_return(fake_bin)
+          subject.s3_bin.should eq fake_bin
+        end
+      end
+    end
+  end
 end
+