From e571779f5aac5ca13b5019467cb2dec76a3ab533 Mon Sep 17 00:00:00 2001
From: Frederick Cheung <frederick.cheung@gmail.com>
Date: Sun, 24 Jun 2012 11:58:32 +0100
Subject: [PATCH] support fog's new use_iam_profile option

---
 lib/dragonfly/data_storage/s3data_store.rb      | 17 ++++++++++++-----
 .../data_storage/s3_data_store_spec.rb          | 10 ++++++++++
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/lib/dragonfly/data_storage/s3data_store.rb b/lib/dragonfly/data_storage/s3data_store.rb
index 7e7ee66e3..a539a3820 100644
--- a/lib/dragonfly/data_storage/s3data_store.rb
+++ b/lib/dragonfly/data_storage/s3data_store.rb
@@ -12,6 +12,7 @@ class S3DataStore
       configurable_attr :access_key_id
       configurable_attr :secret_access_key
       configurable_attr :region
+      configurable_attr :use_iam_profile
       configurable_attr :use_filesystem, true
       configurable_attr :storage_headers, {'x-amz-acl' => 'public-read'}
       configurable_attr :url_scheme, 'http'
@@ -33,6 +34,7 @@ def initialize(opts={})
         self.access_key_id = opts[:access_key_id]
         self.secret_access_key = opts[:secret_access_key]
         self.region = opts[:region]
+        self.use_iam_profile = opts[:use_iam_profile]
       end
 
       def store(temp_object, opts={})
@@ -96,12 +98,13 @@ def domain
 
       def storage
         @storage ||= begin
-          storage = Fog::Storage.new(
+          storage = Fog::Storage.new({
             :provider => 'AWS',
             :aws_access_key_id => access_key_id,
             :aws_secret_access_key => secret_access_key,
-            :region => region
-          )
+            :region => region,
+            :use_iam_profile => use_iam_profile
+          }.reject {|name, option| option.nil?})
           storage.sync_clock
           storage
         end
@@ -118,8 +121,12 @@ def bucket_exists?
 
       def ensure_configured
         unless @configured
-          [:bucket_name, :access_key_id, :secret_access_key].each do |attr|
-            raise NotConfigured, "You need to configure #{self.class.name} with #{attr}" if send(attr).nil?
+          if use_iam_profile
+            raise NotConfigured, "You need to configure #{self.class.name} with #{attr}" if bucket_name.nil?
+          else
+            [:bucket_name, :access_key_id, :secret_access_key].each do |attr|
+              raise NotConfigured, "You need to configure #{self.class.name} with #{attr}" if send(attr).nil?
+            end
           end
           @configured = true
         end
diff --git a/spec/dragonfly/data_storage/s3_data_store_spec.rb b/spec/dragonfly/data_storage/s3_data_store_spec.rb
index 8b5139b45..43defaf5a 100644
--- a/spec/dragonfly/data_storage/s3_data_store_spec.rb
+++ b/spec/dragonfly/data_storage/s3_data_store_spec.rb
@@ -176,6 +176,16 @@
       @data_store.secret_access_key = nil
       proc{ @data_store.retrieve('asdf') }.should raise_error(Dragonfly::Configurable::NotConfigured)
     end
+    
+    if !enabled #this will fail since the specs are not running on an ec2 instance with an iam role defined
+      it 'should allow missing secret key and access key on store if iam profiles are allowed' do
+        @data_store.use_iam_profile = true
+        @data_store.secret_access_key = nil
+        @data_store.access_key_id = nil
+        proc{ @data_store.store(@temp_object) }.should_not raise_error(Dragonfly::Configurable::NotConfigured)
+      end
+    end
+      
   end
 
   describe "autocreating the bucket" do