site.rb in nanoc3-3.2.0a1

- old
+ new

@@ -37,17 +37,20 @@
     # The default configuration for a site. A site's configuration overrides
     # these options: when a {Nanoc3::Site} is created with a configuration
     # that lacks some options, the default value will be taken from
     # `DEFAULT_CONFIG`.
     DEFAULT_CONFIG = {
-      :text_extensions    => %w( css erb haml htm html js less markdown md php rb sass scss txt xhtml xml ),
+      :text_extensions    => %w( css erb haml htm html js less markdown md php rb sass txt xml ),
       :output_dir         => 'output',
       :data_sources       => [ {} ],
       :index_filenames    => [ 'index.html' ],
       :enable_output_diff => false
     }
 
+    # The name of the file where checksums will be stored.
+    CHECKSUMS_FILE_NAME = 'tmp/checksums'
+
     # The site configuration. The configuration has the following keys:
     #
     # * `text_extensions` ({Array<String>}) - A list of file extensions that
     #   will cause nanoc to threat the file as textual instead of binary. When
     #   the data source finds a content file with an extension that is
@@ -87,27 +90,37 @@
     #   would need the username of the account from which to fetch tweets.
     #
     # @return [Hash] The site configuration
     attr_reader :config
 
-    # @return [Time] The timestamp when the site configuration was last
-    # modified
-    attr_reader :config_mtime
+    # @return [String] The checksum of the site configuration that was in
+    #   effect during the previous site compilation
+    attr_accessor :old_config_checksum
 
-    # @return [Time] The timestamp when the rules were last modified
-    attr_reader :rules_mtime
+    # @return [String] The current, up-to-date checksum of the site
+    #   configuration
+    attr_reader   :new_config_checksum
 
+    # @return [String] The checksum of the rules file that was in effect
+    #   during the previous site compilation
+    attr_accessor :old_rules_checksum
+
+    # @return [String] The current, up-to-date checksum of the rules file
+    attr_reader   :new_rules_checksum
+
     # @return [Proc] The code block that will be executed after all data is
-    # loaded but before the site is compiled
+    #   loaded but before the site is compiled
     attr_accessor :preprocessor
 
     # Creates a site object for the site specified by the given
     # `dir_or_config_hash` argument.
     #
     # @param [Hash, String] dir_or_config_hash If a string, contains the path
-    # to the site directory; if a hash, contains the site configuration.
+    #   to the site directory; if a hash, contains the site configuration.
     def initialize(dir_or_config_hash)
+      @new_checksums = {}
+
       build_config(dir_or_config_hash)
 
       @code_snippets_loaded = false
       @items_loaded         = false
       @layouts_loaded       = false
@@ -123,14 +136,14 @@
 
     # Returns the data sources for this site. Will create a new data source if
     # none exists yet.
     #
     # @return [Array<Nanoc3::DataSource>] The list of data sources for this
-    # site
+    #   site
     #
     # @raise [Nanoc3::Errors::UnknownDataSource] if the site configuration
-    # specifies an unknown data source
+    #   specifies an unknown data source
     def data_sources
       @data_sources ||= begin
         @config[:data_sources].map do |data_source_hash|
           # Get data source class
           data_source_class = Nanoc3::DataSource.named(data_source_hash[:type])
@@ -160,11 +173,11 @@
     # with the site and fetch all site data. The site data is cached, so
     # calling this method will not have any effect the second time, unless
     # the `force` parameter is true.
     #
     # @param [Boolean] force If true, will force load the site data even if it
-    # has been loaded before, to circumvent caching issues
+    #   has been loaded before, to circumvent caching issues
     #
     # @return [void]
     def load_data(force=false)
       # Don't load data twice
       return if instance_variable_defined?(:@data_loaded) && @data_loaded && !force
@@ -190,41 +203,65 @@
     end
 
     # Returns this site’s code snippets.
     #
     # @return [Array<Nanoc3::CodeSnippet>] The list of code snippets in this
-    # site
+    #   site
     #
     # @raise [Nanoc3::Errors::DataNotYetAvailable] if the site data hasn’t
-    # been loaded yet (call {#load_data} to load the site data)
+    #   been loaded yet (call {#load_data} to load the site data)
     def code_snippets
       raise Nanoc3::Errors::DataNotYetAvailable.new('Code snippets', false) unless @code_snippets_loaded
       @code_snippets
     end
 
     # Returns this site’s items.
     #
     # @return [Array<Nanoc3::Item>] The list of items in this site
     #
     # @raise [Nanoc3::Errors::DataNotYetAvailable] if the site data hasn’t
-    # been loaded yet (call {#load_data} to load the site data)
+    #   been loaded yet (call {#load_data} to load the site data)
     def items
       raise Nanoc3::Errors::DataNotYetAvailable.new('Items', true) unless @items_loaded
       @items
     end
 
     # Returns this site’s layouts.
     #
     # @return [Array<Nanoc3::Layouts>] The list of layout in this site
     #
     # @raise [Nanoc3::Errors::DataNotYetAvailable] if the site data hasn’t
-    # been loaded yet (call {#load_data} to load the site data)
+    #   been loaded yet (call {#load_data} to load the site data)
     def layouts
       raise Nanoc3::Errors::DataNotYetAvailable.new('Layouts', true) unless @layouts_loaded
       @layouts
     end
 
+    # Stores the checksums into the checksums file.
+    #
+    # @return [void]
+    def store_checksums
+      # Store
+      FileUtils.mkdir_p(File.dirname(CHECKSUMS_FILE_NAME))
+      store = PStore.new(CHECKSUMS_FILE_NAME)
+      store.transaction do
+        store[:checksums] = @new_checksums || {}
+      end
+    end
+
+    # @return [Boolean] true if the site configuration was modified since the
+    #   site was last compiled, false otherwise
+    def config_outdated?
+      !self.old_config_checksum || !self.new_config_checksum || self.old_config_checksum != self.new_config_checksum
+    end
+
+    # @return [Boolean] true if the rules were modified since the site was
+    #   last compiled, false otherwise
+    def rules_outdated?
+      !self.old_rules_checksum || !self.new_rules_checksum || self.old_rules_checksum != self.new_rules_checksum
+    end
+
   private
 
     # Returns the Nanoc3::CompilerDSL that should be used for this site.
     def dsl
       @dsl ||= Nanoc3::CompilerDSL.new(self)
@@ -238,14 +275,20 @@
       # Get code snippets
       @code_snippets = Dir['lib/**/*.rb'].sort.map do |filename|
         Nanoc3::CodeSnippet.new(
           File.read(filename),
           filename,
-          File.stat(filename).mtime
+          :checksum => Nanoc3::Checksummer.checksum_for(filename)
         )
       end
 
+      # Set checksums
+      @code_snippets.each do |cs|
+        cs.old_checksum = old_checksum_for(:code_snippet, cs.filename)
+        @new_checksums[ [ :code_snippet, cs.filename ] ] = cs.new_checksum
+      end
+
       # Execute code snippets
       @code_snippets.each { |cs| cs.load }
 
       @code_snippets_loaded = true
     end
@@ -255,12 +298,14 @@
       # Find rules file
       rules_filename = [ 'Rules', 'rules', 'Rules.rb', 'rules.rb' ].find { |f| File.file?(f) }
       raise Nanoc3::Errors::NoRulesFileFound.new if rules_filename.nil?
 
       # Get rule data
-      @rules       = File.read(rules_filename)
-      @rules_mtime = File.stat(rules_filename).mtime
+      @rules = File.read(rules_filename)
+      @new_rules_checksum = Nanoc3::Checksummer.checksum_for(rules_filename)
+      @old_rules_checksum = old_checksum_for(:misc, 'Rules')
+      @new_checksums[ [ :misc, 'Rules' ] ] = @new_rules_checksum
 
       # Load DSL
       dsl.instance_eval(@rules, "./#{rules_filename}")
     end
 
@@ -272,10 +317,16 @@
         items_in_ds = ds.items
         items_in_ds.each { |i| i.identifier = File.join(ds.items_root, i.identifier) }
         @items.concat(items_in_ds)
       end
 
+      # Set checksums
+      @items.each do |i|
+        i.old_checksum = old_checksum_for(:item, i.identifier)
+        @new_checksums[ [ :item, i.identifier ] ] = i.new_checksum
+      end
+
       @items_loaded = true
     end
 
     # Loads this site’s layouts.
     def load_layouts
@@ -284,10 +335,16 @@
         layouts_in_ds = ds.layouts
         layouts_in_ds.each { |i| i.identifier = File.join(ds.layouts_root, i.identifier) }
         @layouts.concat(layouts_in_ds)
       end
 
+      # Set checksums
+      @layouts.each do |l|
+        l.old_checksum = old_checksum_for(:layout, l.identifier)
+        @new_checksums[ [ :layout, l.identifier ] ] = l.new_checksum
+      end
+
       @layouts_loaded = true
     end
 
     # Links items, layouts and code snippets to the site.
     def link_everything_to_site
@@ -335,56 +392,55 @@
 
     # Determines the paths of all item representations.
     def route_reps
       reps = @items.map { |i| i.reps }.flatten
       reps.each do |rep|
-        # Find matching rule
-        rule = self.compiler.routing_rule_for(rep)
-        raise Nanoc3::Errors::NoMatchingRoutingRuleFound.new(rep) if rule.nil?
+        # Find matching rules
+        rules = self.compiler.routing_rules_for(rep)
+        raise Nanoc3::Errors::NoMatchingRoutingRuleFound.new(rep) if rules[:last].nil?
 
-        # Get basic path by applying matching rule
-        basic_path = rule.apply_to(rep)
-        next if basic_path.nil?
-        if basic_path !~ %r{^/}
-          raise RuntimeError, "The path returned for the #{rep.inspect} item representation, “#{basic_path}”, does not start with a slash. Please ensure that all routing rules return a path that starts with a slash.".make_compatible_with_env
-        end
+        rules.each_pair do |snapshot, rule|
+          # Get basic path by applying matching rule
+          basic_path = rule.apply_to(rep)
+          next if basic_path.nil?
 
-        # Get raw path by prepending output directory
-        rep.raw_path = self.config[:output_dir] + basic_path
+          # Get raw path by prepending output directory
+          rep.raw_paths[snapshot] = self.config[:output_dir] + basic_path
 
-        # Get normal path by stripping index filename
-        rep.path = basic_path
-        self.config[:index_filenames].each do |index_filename|
-          if rep.path[-index_filename.length..-1] == index_filename
-            # Strip and stop
-            rep.path = rep.path[0..-index_filename.length-1]
-            break
+          # Get normal path by stripping index filename
+          rep.paths[snapshot] = basic_path
+          self.config[:index_filenames].each do |index_filename|
+            if rep.paths[snapshot][-index_filename.length..-1] == index_filename
+              # Strip and stop
+              rep.paths[snapshot] = rep.paths[snapshot][0..-index_filename.length-1]
+              break
+            end
           end
         end
       end
     end
 
     # Builds the configuration hash based on the given argument. Also see
-    # #initialize for details.
+    # {#initialize} for details.
     def build_config(dir_or_config_hash)
       if dir_or_config_hash.is_a? String
-        # Check whether it is supported
-        if dir_or_config_hash != '.'
-          warn 'WARNING: Calling Nanoc3::Site.new with a directory that is not the current working directory is not supported. It is recommended to change the directory before calling Nanoc3::Site.new. For example, instead of Nanoc3::Site.new(\'abc\'), use Dir.chdir(\'abc\') { Nanoc3::Site.new(\'.\') }.'
-        end
-
         # Read config from config.yaml in given dir
         config_path = File.join(dir_or_config_hash, 'config.yaml')
         @config = DEFAULT_CONFIG.merge(YAML.load_file(config_path).symbolize_keys)
         @config[:data_sources].map! { |ds| ds.symbolize_keys }
-        @config_mtime = File.stat(config_path).mtime
+
+        @new_config_checksum = Nanoc3::Checksummer.checksum_for('config.yaml')
+        @new_checksums[ [ :misc, 'config.yaml' ] ] = @new_config_checksum
       else
         # Use passed config hash
         @config = DEFAULT_CONFIG.merge(dir_or_config_hash)
-        @config_mtime = nil
+        @new_config_checksum = nil
       end
 
+      # Build checksum
+      @old_config_checksum = old_checksum_for(:misc, 'config.yaml')
+
       # Merge data sources with default data source config
       @config[:data_sources].map! { |ds| DEFAULT_DATA_SOURCE_CONFIG.merge(ds) }
     end
 
     # Returns a preprocessor context, creating one if none exists yet.
@@ -393,9 +449,41 @@
         :site    => self,
         :config  => self.config,
         :items   => self.items,
         :layouts => self.layouts
       })
+    end
+
+    # Returns the checksums, loads the checksums from the cached checksums
+    # file first if necessary. The checksums returned is a hash in th following
+    # format:
+    #
+    #     {
+    #       [ :layout,       '/identifier/'    ] => checksum,
+    #       [ :item,         '/identifier/'    ] => checksum,
+    #       [ :code_snippet, 'lib/filename.rb' ] => checksum,
+    #     }
+    def checksums
+      return @checksums if @checksums_loaded
+
+      if !File.file?(CHECKSUMS_FILE_NAME)
+        @checksums = {}
+      else
+        require 'pstore'
+        store = PStore.new(CHECKSUMS_FILE_NAME)
+        store.transaction do
+          @checksums = store[:checksums] || {}
+        end
+      end
+
+      @checksums_loaded = true
+      @checksums
+    end
+
+    # Returns the old checksum for the given object.
+    def old_checksum_for(type, identifier)
+      key = [ type, identifier ]
+      checksums[key]
     end
 
   end
 
 end