Add HTTP::IO

app/uploaders/job_artifact_uploader.rb

@@ -18,7 +18,7 @@ class JobArtifactUploader < GitlabUploader
     if file_storage?
       File.open(path, "rb")
     else
-      raise 'Only File System is supported'
+      Gitlab::Ci::Trace::HTTP_IO.new(url, size)
     end
   end
 

lib/gitlab/ci/trace/http_io.rb

+require 'net/http'
+
+##
+#
+# This class is compatible with IO class (https://ruby-doc.org/core-2.3.1/IO.html)
+# source: https://gitlab.com/snippets/1685610
+module Gitlab
+  module Ci
+    class Trace
+      class HTTP_IO
+        BUFFER_SIZE = 128*1024
+
+        attr_reader :uri, :size
+        attr_reader :tell
+        attr_reader :chunk, :chunk_range
+
+        def initialize(url, size)
+          @uri = URI(url)
+          @size = size
+          @tell = 0
+        end
+
+        def close
+        end
+
+        def binmode
+        end
+
+        def path
+          true
+        end
+
+        def seek(pos, where)
+          new_pos =
+            case where
+            when IO::SEEK_END
+              size + pos
+            when IO::SEEK_SET
+              pos
+            when IO::SEEK_CUR
+              tell + pos
+            else
+              -1
+            end
+
+          raise 'new position is outside of file' if new_pos < 0 || new_pos > size
+
+          @tell = new_pos
+        end
+
+        def eof?
+          tell == size
+        end
+
+        def each_line
+          while !eof? do
+            line = read_line
+            yield(line)
+          end
+        end
+
+        def read
+          out = ""
+          loop do
+            data = get_chunk
+            break if data.empty?
+            out += data
+            @tell += data.bytesize
+          end
+          out
+        end
+
+        def readline
+          out = ""
+
+          data = get_chunk
+          while !data.empty? do
+            new_line = data.index('\n')
+            if !new_line.nil?
+              out = data[0..new_line]
+              @tell += new_line+1
+              break
+            elsif data.empty?
+              break
+            else
+              out = data
+              @tell += data.bytesize
+              data = get_chunk
+            end
+          end
+
+          out
+        end
+
+        def write(data)
+          throw NotImplementedException
+        end
+
+        def truncate(offset)
+          throw NotImplementedException
+        end
+
+        def flush
+          throw NotImplementedException
+        end
+
+        def present?
+          true
+        end
+
+        private
+
+        def in_range?
+          @chunk_range&.include?(tell)
+        end
+
+        def get_chunk
+          unless in_range?
+            response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: uri.scheme == 'https') do |http|
+              http.request(request)
+            end
+
+            @chunk = response.body.force_encoding(Encoding::BINARY)
+            @chunk_range = response.content_range
+          end
+
+          @chunk[chunk_offset .. BUFFER_SIZE]
+        end
+
+        def request
+          Net::HTTP::Get.new(uri).tap do |request|
+            puts "Requesting chunk: #{chunk_start}-#{chunk_end}"
+            request.set_range(chunk_start, BUFFER_SIZE)
+          end
+        end
+
+        def chunk_offset
+          tell % BUFFER_SIZE
+        end
+
+        def chunk_start
+          (tell / BUFFER_SIZE) * BUFFER_SIZE
+        end
+
+        def chunk_end
+          [chunk_start + BUFFER_SIZE, size].min
+        end
+      end
+    end
+  end
+end