1 files changed, 42 insertions, 0 deletions
diff --git a/lib/banzai/filter/markdown_filter.rb b/lib/banzai/filter/markdown_filter.rb
new file mode 100644
index 00000000000..0072bab1f99
--- /dev/null
+++ b/lib/banzai/filter/markdown_filter.rb
@@ -0,0 +1,42 @@
+require 'banzai'
+require 'html/pipeline/filter'
+
+module Banzai
+  module Filter
+    class MarkdownFilter < HTML::Pipeline::TextFilter
+      def initialize(text, context = nil, result = nil)
+        super text, context, result
+        @text = @text.gsub "\r", ''
+      end
+
+      def call
+        html = self.class.renderer.render(@text)
+        html.rstrip!
+        html
+      end
+
+      private
+
+      def self.redcarpet_options
+        # https://github.com/vmg/redcarpet#and-its-like-really-simple-to-use
+        @redcarpet_options ||= {
+          fenced_code_blocks:  true,
+          footnotes:           true,
+          lax_spacing:         true,
+          no_intra_emphasis:   true,
+          space_after_headers: true,
+          strikethrough:       true,
+          superscript:         true,
+          tables:              true
+        }.freeze
+      end
+
+      def self.renderer
+        @renderer ||= begin
+          renderer = Redcarpet::Render::HTML.new
+          Redcarpet::Markdown.new(renderer, redcarpet_options)
+        end
+      end
+    end
+  end
+end