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Diffstat (limited to 'actionpack/lib/action_controller/routing/builder.rb')
-rw-r--r-- | actionpack/lib/action_controller/routing/builder.rb | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/routing/builder.rb b/actionpack/lib/action_controller/routing/builder.rb new file mode 100644 index 0000000000..69943d4230 --- /dev/null +++ b/actionpack/lib/action_controller/routing/builder.rb @@ -0,0 +1,197 @@ +module ActionController + module Routing + class RouteBuilder #:nodoc: + attr_accessor :separators, :optional_separators + + def initialize + self.separators = Routing::SEPARATORS + self.optional_separators = %w( / ) + end + + def separator_pattern(inverted = false) + "[#{'^' if inverted}#{Regexp.escape(separators.join)}]" + end + + def interval_regexp + Regexp.new "(.*?)(#{separators.source}|$)" + end + + # Accepts a "route path" (a string defining a route), and returns the array + # of segments that corresponds to it. Note that the segment array is only + # partially initialized--the defaults and requirements, for instance, need + # to be set separately, via the #assign_route_options method, and the + # #optional? method for each segment will not be reliable until after + # #assign_route_options is called, as well. + def segments_for_route_path(path) + rest, segments = path, [] + + until rest.empty? + segment, rest = segment_for rest + segments << segment + end + segments + end + + # A factory method that returns a new segment instance appropriate for the + # format of the given string. + def segment_for(string) + segment = case string + when /\A:(\w+)/ + key = $1.to_sym + case key + when :controller then ControllerSegment.new(key) + else DynamicSegment.new key + end + when /\A\*(\w+)/ then PathSegment.new($1.to_sym, :optional => true) + when /\A\?(.*?)\?/ + returning segment = StaticSegment.new($1) do + segment.is_optional = true + end + when /\A(#{separator_pattern(:inverted)}+)/ then StaticSegment.new($1) + when Regexp.new(separator_pattern) then + returning segment = DividerSegment.new($&) do + segment.is_optional = (optional_separators.include? $&) + end + end + [segment, $~.post_match] + end + + # Split the given hash of options into requirement and default hashes. The + # segments are passed alongside in order to distinguish between default values + # and requirements. + def divide_route_options(segments, options) + options = options.dup + + if options[:namespace] + options[:controller] = "#{options[:path_prefix]}/#{options[:controller]}" + options.delete(:path_prefix) + options.delete(:name_prefix) + options.delete(:namespace) + end + + requirements = (options.delete(:requirements) || {}).dup + defaults = (options.delete(:defaults) || {}).dup + conditions = (options.delete(:conditions) || {}).dup + + path_keys = segments.collect { |segment| segment.key if segment.respond_to?(:key) }.compact + options.each do |key, value| + hash = (path_keys.include?(key) && ! value.is_a?(Regexp)) ? defaults : requirements + hash[key] = value + end + + [defaults, requirements, conditions] + end + + # Takes a hash of defaults and a hash of requirements, and assigns them to + # the segments. Any unused requirements (which do not correspond to a segment) + # are returned as a hash. + def assign_route_options(segments, defaults, requirements) + route_requirements = {} # Requirements that do not belong to a segment + + segment_named = Proc.new do |key| + segments.detect { |segment| segment.key == key if segment.respond_to?(:key) } + end + + requirements.each do |key, requirement| + segment = segment_named[key] + if segment + raise TypeError, "#{key}: requirements on a path segment must be regular expressions" unless requirement.is_a?(Regexp) + if requirement.source =~ %r{\A(\\A|\^)|(\\Z|\\z|\$)\Z} + raise ArgumentError, "Regexp anchor characters are not allowed in routing requirements: #{requirement.inspect}" + end + segment.regexp = requirement + else + route_requirements[key] = requirement + end + end + + defaults.each do |key, default| + segment = segment_named[key] + raise ArgumentError, "#{key}: No matching segment exists; cannot assign default" unless segment + segment.is_optional = true + segment.default = default.to_param if default + end + + assign_default_route_options(segments) + ensure_required_segments(segments) + route_requirements + end + + # Assign default options, such as 'index' as a default for :action. This + # method must be run *after* user supplied requirements and defaults have + # been applied to the segments. + def assign_default_route_options(segments) + segments.each do |segment| + next unless segment.is_a? DynamicSegment + case segment.key + when :action + if segment.regexp.nil? || segment.regexp.match('index').to_s == 'index' + segment.default ||= 'index' + segment.is_optional = true + end + when :id + if segment.default.nil? && segment.regexp.nil? || segment.regexp =~ '' + segment.is_optional = true + end + end + end + end + + # Makes sure that there are no optional segments that precede a required + # segment. If any are found that precede a required segment, they are + # made required. + def ensure_required_segments(segments) + allow_optional = true + segments.reverse_each do |segment| + allow_optional &&= segment.optional? + if !allow_optional && segment.optional? + unless segment.optionality_implied? + warn "Route segment \"#{segment.to_s}\" cannot be optional because it precedes a required segment. This segment will be required." + end + segment.is_optional = false + elsif allow_optional && segment.respond_to?(:default) && segment.default + # if a segment has a default, then it is optional + segment.is_optional = true + end + end + end + + # Construct and return a route with the given path and options. + def build(path, options) + # Wrap the path with slashes + path = "/#{path}" unless path[0] == ?/ + path = "#{path}/" unless path[-1] == ?/ + + path = "/#{options[:path_prefix].to_s.gsub(/^\//,'')}#{path}" if options[:path_prefix] + + segments = segments_for_route_path(path) + defaults, requirements, conditions = divide_route_options(segments, options) + requirements = assign_route_options(segments, defaults, requirements) + + route = Route.new + + route.segments = segments + route.requirements = requirements + route.conditions = conditions + + if !route.significant_keys.include?(:action) && !route.requirements[:action] + route.requirements[:action] = "index" + route.significant_keys << :action + end + + # Routes cannot use the current string interpolation method + # if there are user-supplied :requirements as the interpolation + # code won't raise RoutingErrors when generating + if options.key?(:requirements) || route.requirements.keys.to_set != Routing::ALLOWED_REQUIREMENTS_FOR_OPTIMISATION + route.optimise = false + end + + if !route.significant_keys.include?(:controller) + raise ArgumentError, "Illegal route: the :controller must be specified!" + end + + route + end + end + end +end
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