From ed58cc3f47706985b08753979fdf9ef798105e16 Mon Sep 17 00:00:00 2001
From: Frederick Cheung <frederick.cheung@gmail.com>
Date: Wed, 17 May 2017 17:38:17 +0100
Subject: [PATCH] Handle multipart upload of empty files

---
 lib/fog/aws/models/storage/file.rb |  5 +++++
 tests/models/storage/file_tests.rb | 12 ++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/lib/fog/aws/models/storage/file.rb b/lib/fog/aws/models/storage/file.rb
index 6336d8716..df042a684 100644
--- a/lib/fog/aws/models/storage/file.rb
+++ b/lib/fog/aws/models/storage/file.rb
@@ -276,6 +276,11 @@ module Fog
             part_tags << part_upload.headers["ETag"]
           end
 
+          if part_tags.empty? #it is an error to have a multipart upload with no parts
+            part_upload = service.upload_part(directory.key, key, upload_id, 1, '', part_headers('', options))
+            part_tags << part_upload.headers["ETag"]
+          end
+
         rescue
           # Abort the upload & reraise
           service.abort_multipart_upload(directory.key, key, upload_id) if upload_id
diff --git a/tests/models/storage/file_tests.rb b/tests/models/storage/file_tests.rb
index d4dc9fef0..1c3c7ce33 100644
--- a/tests/models/storage/file_tests.rb
+++ b/tests/models/storage/file_tests.rb
@@ -74,6 +74,18 @@ Shindo.tests("Storage[:aws] | file", ["aws"]) do
 
     end
 
+    tests("multipart upload with empty file") do
+      pending if Fog.mocking?
+
+      @empty_file = Tempfile.new("fog-test-aws-s3-multipart-empty")
+     
+      tests("#save(:multipart_chunk_size => 5242880)").succeeds do
+        @directory.files.create(:key => 'empty-multipart-upload', :body => @empty_file, :multipart_chunk_size => 5242880)
+      end
+
+      @empty_file.close
+    end
+
     tests("multipart upload with customer encryption").returns(true) do
       pending if Fog.mocking?