support <changefreq> and <priority> lambdas

lib/big_sitemap.rb

@@ -52,12 +52,17 @@ def generate
       with_sitemap(model.name.tableize) do |sitemap|
         find_options = options.dup
         changefreq = find_options.delete(:change_frequency) || 'weekly'
+        priority = find_options.delete(:priority)
+
         find_options[:batch_size] ||= @options[:batch_size]
         timestamp_column = model.column_names.find { |col| TIMESTAMP_COLUMNS.include? col }
 
         model.find_each(find_options) do |record|
           last_updated = timestamp_column && record.read_attribute(timestamp_column)
-          sitemap.add_url!(polymorphic_url(record), last_updated, changefreq)
+          freq = changefreq.is_a?(Proc) ? changefreq.call(record) : changefreq
+          pri = priority.is_a?(Proc) ? priority.call(record) : priority
+
+          sitemap.add_url!(polymorphic_url(record), last_updated, freq, pri)
         end
       end
     end

lib/big_sitemap/builder.rb

@@ -23,13 +23,14 @@ def initialize(options)
       _init_document
     end
 
-    def add_url!(url, time = nil, frequency = nil)
+    def add_url!(url, time = nil, frequency = nil, priority = nil)
       _rotate if @max_urls == @urls
 
       tag!(@index ? 'sitemap' : 'url') do
         loc url
-        lastmod time.to_s(:sitemap) unless time.nil?
-        changefreq frequency unless frequency.nil?
+        lastmod(time.to_s(:sitemap)) unless time.nil?
+        changefreq(frequency) unless frequency.nil?
+        priority(priority) unless priority.nil?
       end
       @urls += 1
     end

spec/builder_spec.rb

@@ -10,7 +10,7 @@
     end
 
     it "should add location" do
-      @xml.add_url!("http://example.com/mooslav", @time, "all the f-in time")
+      @xml.add_url!("http://example.com/mooslav", @time)
       @xml.close!
 
       result.should == strip(<<-XML)
@@ -19,11 +19,22 @@
           <url>
             <loc>http://example.com/mooslav</loc>
             <lastmod>#{@time_string}</lastmod>
-            <changefreq>all the f-in time</changefreq>
           </url>
         </urlset>
       XML
     end
+
+    it "should support frequency" do
+      @xml.add_url!("http://example.com/mooslav", nil, "all the f-in time")
+      @xml.close!
+      result.should include("<changefreq>all the f-in time</changefreq>")
+    end
+
+    it "should support priority" do
+      @xml.add_url!("http://example.com/mooslav", nil, nil, 0.6)
+      @xml.close!
+      result.should include("<priority>0.6</priority>")
+    end
 
     it "should rotate files when it reaches maximum number of URLs" do
       @xml.add_url!("http://example.com/loc1", @time)