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
def multiline_regexp?(expression)
expression.options & Regexp::MULTILINE == Regexp::MULTILINE
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
# <tt>optional?</tt> 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\?(.*?)\?/
StaticSegment.new($1, :optional => true)
when /\A(#{separator_pattern(:inverted)}+)/ then StaticSegment.new($1)
when Regexp.new(separator_pattern) then
DividerSegment.new($&, :optional => (optional_separators.include? $&))
end
[segment, $~.post_match]
end
# Split the given hash of options into requirement and default hashes. The
# segments are passed alongside in order to distinguish between default values
# and requirements.
def divide_route_options(segments, options)
options = options.dup
if options[:namespace]
options[:controller] = "#{options.delete(:namespace).sub(/\/$/, '')}/#{options[:controller]}"
options.delete(:path_prefix)
options.delete(:name_prefix)
end
requirements = (options.delete(:requirements) || {}).dup
defaults = (options.delete(:defaults) || {}).dup
conditions = (options.delete(:conditions) || {}).dup
validate_route_conditions(conditions)
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
if multiline_regexp?(requirement)
raise ArgumentError, "Regexp multiline option 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 <tt>:action</tt>. 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)
# TODO: Segments should be frozen on initialize
segments.each { |segment| segment.freeze }
route = Route.new(segments, requirements, conditions)
if !route.significant_keys.include?(:controller)
raise ArgumentError, "Illegal route: the :controller must be specified!"
end
route.freeze
end
private
def validate_route_conditions(conditions)
if method = conditions[:method]
[method].flatten.each do |m|
if m == :head
raise ArgumentError, "HTTP method HEAD is invalid in route conditions. Rails processes HEAD requests the same as GETs, returning just the response headers"
end
unless HTTP_METHODS.include?(m.to_sym)
raise ArgumentError, "Invalid HTTP method specified in route conditions: #{conditions.inspect}"
end
end
end
end
end
end
end
