Allow streaming io objects into Gitaly

This allows us to set the encoding of an IO passed without reading it
into memory.

This is useful if we want to stream files into Gitaly. Like we do when
uploading a new file to the repository.

6 files changed, 22 insertions, 11 deletions

diff --git a/app/controllers/projects/blob_controller.rb b/app/controllers/projects/blob_controller.rb
index 909b17e9c8d..7e072788fc9 100644
--- a/app/controllers/projects/blob_controller.rb
+++ b/app/controllers/projects/blob_controller.rb
@@ -172,8 +172,7 @@ class Projects::BlobController < Projects::ApplicationController
       end
 
     if params[:file].present?
-      params[:content] = Base64.encode64(params[:file].read)
-      params[:encoding] = 'base64'
+      params[:content] = params[:file]
     end
 
     @commit_params = {
diff --git a/lib/gitlab/encoding_helper.rb b/lib/gitlab/encoding_helper.rb
index a4a154c80f7..5a61a7f5d60 100644
--- a/lib/gitlab/encoding_helper.rb
+++ b/lib/gitlab/encoding_helper.rb
@@ -76,8 +76,11 @@ module Gitlab
       str.dup.force_encoding(Encoding::ASCII_8BIT)
     end
 
-    def binary_stringio(str)
-      StringIO.new(str.freeze || '').tap { |io| io.set_encoding(Encoding::ASCII_8BIT) }
+    def binary_io(str_or_io)
+      io = str_or_io.to_io.dup if str_or_io.respond_to?(:to_io)
+      io ||= StringIO.new(str_or_io.to_s.freeze)
+
+      io.tap { |io| io.set_encoding(Encoding::ASCII_8BIT) }
     end
 
     private
diff --git a/lib/gitlab/gitaly_client/conflicts_service.rb b/lib/gitlab/gitaly_client/conflicts_service.rb
index 6304f998563..077b63205a8 100644
--- a/lib/gitlab/gitaly_client/conflicts_service.rb
+++ b/lib/gitlab/gitaly_client/conflicts_service.rb
@@ -37,7 +37,7 @@ module Gitlab
       end
 
       def resolve_conflicts(target_repository, resolution, source_branch, target_branch)
-        reader = binary_stringio(resolution.files.to_json)
+        reader = binary_io(resolution.files.to_json)
 
         req_enum = Enumerator.new do |y|
           header = resolve_conflicts_request_header(target_repository, resolution, source_branch, target_branch)
diff --git a/lib/gitlab/gitaly_client/operation_service.rb b/lib/gitlab/gitaly_client/operation_service.rb
index 2528208440e..b0f328ce3d4 100644
--- a/lib/gitlab/gitaly_client/operation_service.rb
+++ b/lib/gitlab/gitaly_client/operation_service.rb
@@ -294,7 +294,7 @@ module Gitlab
               action: Gitaly::UserCommitFilesAction.new(header: action_header)
             )
 
-            reader = binary_stringio(action[:content])
+            reader = binary_io(action[:content])
 
             until reader.eof?
               chunk = reader.read(MAX_MSG_SIZE)
@@ -327,7 +327,7 @@ module Gitlab
           user: Gitlab::Git::User.from_gitlab(user).to_gitaly,
           target_branch: encode_binary(branch_name)
         )
-        reader = binary_stringio(patches)
+        reader = binary_io(patches)
 
         chunks = Enumerator.new do |chunk|
           chunk.yield Gitaly::UserApplyPatchRequest.new(header: header)
diff --git a/lib/gitlab/gitaly_client/wiki_service.rb b/lib/gitlab/gitaly_client/wiki_service.rb
index 2b3d622af4d..15c9463e2f2 100644
--- a/lib/gitlab/gitaly_client/wiki_service.rb
+++ b/lib/gitlab/gitaly_client/wiki_service.rb
@@ -22,7 +22,7 @@ module Gitlab
           commit_details: gitaly_commit_details(commit_details)
         )
 
-        strio = binary_stringio(content)
+        strio = binary_io(content)
 
         enum = Enumerator.new do |y|
           until strio.eof?
@@ -49,7 +49,7 @@ module Gitlab
           commit_details: gitaly_commit_details(commit_details)
         )
 
-        strio = binary_stringio(content)
+        strio = binary_io(content)
 
         enum = Enumerator.new do |y|
           until strio.eof?
diff --git a/spec/lib/gitlab/encoding_helper_spec.rb b/spec/lib/gitlab/encoding_helper_spec.rb
index 429816efec3..88ea98eb1e1 100644
--- a/spec/lib/gitlab/encoding_helper_spec.rb
+++ b/spec/lib/gitlab/encoding_helper_spec.rb
@@ -189,14 +189,23 @@ describe Gitlab::EncodingHelper do
     end
   end
 
-  describe '#binary_stringio' do
+  describe '#binary_io' do
     it 'does not mutate the original string encoding' do
       test = 'my-test'
 
-      io_stream = ext_class.binary_stringio(test)
+      io_stream = ext_class.binary_io(test)
 
       expect(io_stream.external_encoding.name).to eq('ASCII-8BIT')
       expect(test.encoding.name).to eq('UTF-8')
     end
+
+    it 'returns a copy of the IO with the correct encoding' do
+      test = fixture_file_upload('spec/fixtures/doc_sample.txt').to_io
+
+      io_stream = ext_class.binary_io(test)
+
+      expect(io_stream.external_encoding.name).to eq('ASCII-8BIT')
+      expect(test).not_to eq(io_stream)
+    end
   end
 end