Make HTTPIO compatible with multi-byte chars (Extracted from ChunkedIO)

lib/gitlab/ci/trace/http_io.rb

@@ -75,18 +75,28 @@ module Gitlab
           end
         end
 
-        def read(length = nil)
+        def read(length = nil, outbuf = "")
           out = ""
 
-          until eof? || (length && out.length >= length)
+          length ||= size - tell
+
+          until length <= 0 || eof?
             data = get_chunk
             break if data.empty?
 
-            out << data
-            @tell += data.bytesize
+            chunk_bytes = [BUFFER_SIZE - chunk_offset, length].min
+            chunk_data = data.byteslice(0, chunk_bytes)
+
+            out << chunk_data
+            @tell += chunk_data.bytesize
+            length -= chunk_data.bytesize
           end
 
-          out = out[0, length] if length && out.length > length
+          # If outbuf is passed, we put the output into the buffer. This supports IO.copy_stream functionality
+          if outbuf
+            outbuf.slice!(0, outbuf.bytesize)
+            outbuf << out
+          end
 
           out
         end
@@ -158,7 +168,7 @@ module Gitlab
             # Provider: GCS
             # - When the file size is larger than requested Content-range, the Content-range is included in responces with Net::HTTPPartialContent 206
             # - When the file size is smaller than requested Content-range, the Content-range is included in responces with Net::HTTPOK 200
-            @chunk_range ||= (chunk_start...(chunk_start + @chunk.length))
+            @chunk_range ||= (chunk_start...(chunk_start + @chunk.bytesize))
           end
 
           @chunk[chunk_offset..BUFFER_SIZE]

spec/support/http_io/http_io_helpers.rb

@@ -44,10 +44,11 @@ module HttpIOHelpers
 
   def remote_trace_body
     @remote_trace_body ||= File.read(expand_fixture_path('trace/sample_trace'))
+      .force_encoding(Encoding::BINARY)
   end
 
   def remote_trace_size
-    remote_trace_body.length
+    remote_trace_body.bytesize
   end
 
   def set_smaller_buffer_size_than(file_size)