Copy binary files instead of rendering through MM. Closes #643. Closes #699

CHANGELOG.md

@@ -1,6 +1,8 @@
 Master
 ===
 
+* Directly send binary files in preview and copy them in build, avoiding reading large binary files into memory for rendering. #643 #699
+
 3.0.7
 ====
 * Turn html5 boilerplate into a layout

middleman-core/lib/middleman-core/cli/build.rb

@@ -117,16 +117,20 @@ module Middleman::Cli
         build_dir = self.class.shared_instance.config[:build_dir]
         output_file = File.join(build_dir, resource.destination_path)
 
-        begin
-          response = self.class.shared_rack.get(URI.escape(resource.destination_path))
+        if resource.binary?
+          copy_file(resource.source_file, output_file)
+        else
+          begin
+            response = self.class.shared_rack.get(URI.escape(resource.destination_path))
 
-          if response.status == 200
-            create_file(output_file, response.body)
-          else
-            handle_error(output_file, response.body)
+            if response.status == 200
+              create_file(output_file, response.body)
+            else
+              handle_error(output_file, response.body)
+            end
+          rescue => e
+            handle_error(output_file, "#{e}\n#{e.backtrace.join("\n")}", e)
           end
-        rescue => e
-          handle_error(output_file, "#{e}\n#{e.backtrace.join("\n")}", e)
         end
 
         output_file

middleman-core/lib/middleman-core/core_extensions/request.rb

@@ -245,6 +245,9 @@ module Middleman
           # Return 404 if not in sitemap
           return not_found(res, request_path) unless resource && !resource.ignored?
 
+          # If this path is a binary file, send it immediately
+          return send_file(resource.source_file, env, res) if resource.binary?
+
           current_path = resource.destination_path
 
           # Set a HTTP content type based on the request's extensions

middleman-core/lib/middleman-core/sitemap/resource.rb

@@ -146,6 +146,14 @@ module Middleman
         end
         File.join(app.respond_to?(:http_prefix) ? app.http_prefix : '/', url_path)
       end
+
+      # Whether the source file is binary.
+      #
+      # @retrun [Boolean]
+      def binary?
+        s = (File.read(source_file, File.stat(source_file).blksize) || "").split(//)
+        ((s.size - s.grep(" ".."~").size) / s.size.to_f) > 0.30
+      end
     end
   end
 end