Collections

middleman-core/lib/middleman-core/util.rb

@@ -14,6 +14,11 @@ require 'rack/mime'
 # DbC
 require 'middleman-core/contracts'
 
+# For URI templating
+require 'addressable/template'
+require 'active_support/inflector'
+require 'active_support/inflector/transliterate'
+
 module Middleman
   module Util
     include Contracts
@@ -384,5 +389,93 @@ module Middleman
         resource_url
       end
     end
+
+    # Handy methods for dealing with URI templates. Mix into whatever class.
+    module UriTemplates
+      module_function
+
+      # Given a URI template string, make an Addressable::Template
+      # This supports the legacy middleman-blog/Sinatra style :colon
+      # URI templates as well as RFC6570 templates.
+      #
+      # @param [String] tmpl_src URI template source
+      # @return [Addressable::Template] a URI template
+      def uri_template(tmpl_src)
+        # Support the RFC6470 templates directly if people use them
+        if tmpl_src.include?(':')
+          tmpl_src = tmpl_src.gsub(/:([A-Za-z0-9]+)/, '{\1}')
+        end
+
+        Addressable::Template.new ::Middleman::Util.normalize_path(tmpl_src)
+      end
+
+      # Apply a URI template with the given data, producing a normalized
+      # Middleman path.
+      #
+      # @param [Addressable::Template] template
+      # @param [Hash] data
+      # @return [String] normalized path
+      def apply_uri_template(template, data)
+        ::Middleman::Util.normalize_path Addressable::URI.unencode(template.expand(data)).to_s
+      end
+
+      # Use a template to extract parameters from a path, and validate some special (date)
+      # keys. Returns nil if the special keys don't match.
+      #
+      # @param [Addressable::Template] template
+      # @param [String] path
+      def extract_params(template, path)
+        template.extract(path, BlogTemplateProcessor)
+      end
+
+      # Parameterize a string preserving any multibyte characters
+      def safe_parameterize(str)
+        sep = '-'
+
+        # Reimplementation of http://api.rubyonrails.org/classes/ActiveSupport/Inflector.html#method-i-parameterize that preserves un-transliterate-able multibyte chars.
+        parameterized_string = ActiveSupport::Inflector.transliterate(str.to_s).downcase
+        parameterized_string.gsub!(/[^a-z0-9\-_\?]+/, sep)
+
+        parameterized_string.chars.to_a.each_with_index do |char, i|
+          next unless char == '?' && str[i].bytes.count != 1
+          parameterized_string[i] = str[i]
+        end
+
+        re_sep = Regexp.escape(sep)
+        # No more than one of the separator in a row.
+        parameterized_string.gsub!(/#{re_sep}{2,}/, sep)
+        # Remove leading/trailing separator.
+        parameterized_string.gsub!(/^#{re_sep}|#{re_sep}$/, '')
+
+        parameterized_string
+      end
+
+      # Convert a date into a hash of components to strings
+      # suitable for using in a URL template.
+      # @param [DateTime] date
+      # @return [Hash] parameters
+      def date_to_params(date)
+        {
+          year: date.year.to_s,
+          month: date.month.to_s.rjust(2, '0'),
+          day: date.day.to_s.rjust(2, '0')
+        }
+      end
+    end
+
+    # A special template processor that validates date fields
+    # and has an extra-permissive default regex.
+    #
+    # See https://github.com/sporkmonger/addressable/blob/master/lib/addressable/template.rb#L279
+    class BlogTemplateProcessor
+      def self.match(name)
+        case name
+        when 'year' then '\d{4}'
+        when 'month' then '\d{2}'
+        when 'day' then '\d{2}'
+        else '.*?'
+        end
+      end
+    end
   end
 end