aboutsummaryrefslogtreecommitdiffstats
path: root/actionpack/lib/action_dispatch/journey/formatter.rb
blob: 326f4e52f9d22e397e7e4e747d97fdd520cca51d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
require "action_controller/metal/exceptions"

module ActionDispatch
  # :stopdoc:
  module Journey
    # The Formatter class is used for formatting URLs. For example, parameters
    # passed to +url_for+ in Rails will eventually call Formatter#generate.
    class Formatter
      attr_reader :routes

      def initialize(routes)
        @routes = routes
        @cache  = nil
      end

      def generate(name, options, path_parameters, parameterize = nil)
        constraints = path_parameters.merge(options)
        missing_keys = nil

        match_route(name, constraints) do |route|
          parameterized_parts = extract_parameterized_parts(route, options, path_parameters, parameterize)

          # Skip this route unless a name has been provided or it is a
          # standard Rails route since we can't determine whether an options
          # hash passed to url_for matches a Rack application or a redirect.
          next unless name || route.dispatcher?

          missing_keys = missing_keys(route, parameterized_parts)
          next if missing_keys && !missing_keys.empty?
          params = options.dup.delete_if do |key, _|
            parameterized_parts.key?(key) || route.defaults.key?(key)
          end

          defaults       = route.defaults
          required_parts = route.required_parts

          route.parts.reverse_each do |key|
            break if defaults[key].nil? && parameterized_parts[key].present?
            next if parameterized_parts[key].to_s != defaults[key].to_s
            break if required_parts.include?(key)

            parameterized_parts.delete(key)
          end

          return [route.format(parameterized_parts), params]
        end

        unmatched_keys = (missing_keys || []) & constraints.keys
        missing_keys = (missing_keys || []) - unmatched_keys

        message = "No route matches #{Hash[constraints.sort_by { |k, v| k.to_s }].inspect}"
        message << ", missing required keys: #{missing_keys.sort.inspect}" if missing_keys && !missing_keys.empty?
        message << ", possible unmatched constraints: #{unmatched_keys.sort.inspect}" if unmatched_keys && !unmatched_keys.empty?

        raise ActionController::UrlGenerationError, message
      end

      def clear
        @cache = nil
      end

      private

        def extract_parameterized_parts(route, options, recall, parameterize = nil)
          parameterized_parts = recall.merge(options)

          keys_to_keep = route.parts.reverse_each.drop_while { |part|
            !options.key?(part) || (options[part] || recall[part]).nil?
          } | route.required_parts

          parameterized_parts.delete_if do |bad_key, _|
            !keys_to_keep.include?(bad_key)
          end

          if parameterize
            parameterized_parts.each do |k, v|
              parameterized_parts[k] = parameterize.call(k, v)
            end
          end

          parameterized_parts.keep_if { |_, v| v }
          parameterized_parts
        end

        def named_routes
          routes.named_routes
        end

        def match_route(name, options)
          if named_routes.key?(name)
            yield named_routes[name]
          else
            routes = non_recursive(cache, options)

            supplied_keys = options.each_with_object({}) do |(k, v), h|
              h[k.to_s] = true if v
            end

            hash = routes.group_by { |_, r| r.score(supplied_keys) }

            hash.keys.sort.reverse_each do |score|
              break if score < 0

              hash[score].sort_by { |i, _| i }.each do |_, route|
                yield route
              end
            end
          end
        end

        def non_recursive(cache, options)
          routes = []
          queue  = [cache]

          while queue.any?
            c = queue.shift
            routes.concat(c[:___routes]) if c.key?(:___routes)

            options.each do |pair|
              queue << c[pair] if c.key?(pair)
            end
          end

          routes
        end

        module RegexCaseComparator
          DEFAULT_INPUT = /[-_.a-zA-Z0-9]+\/[-_.a-zA-Z0-9]+/
          DEFAULT_REGEX = /\A#{DEFAULT_INPUT}\Z/

          def self.===(regex)
            DEFAULT_INPUT == regex
          end
        end

        # Returns an array populated with missing keys if any are present.
        def missing_keys(route, parts)
          missing_keys = nil
          tests = route.path.requirements
          route.required_parts.each { |key|
            case tests[key]
            when nil
              unless parts[key]
                missing_keys ||= []
                missing_keys << key
              end
            when RegexCaseComparator
              unless RegexCaseComparator::DEFAULT_REGEX === parts[key]
                missing_keys ||= []
                missing_keys << key
              end
            else
              unless /\A#{tests[key]}\Z/ === parts[key]
                missing_keys ||= []
                missing_keys << key
              end
            end
          }
          missing_keys
        end

        def possibles(cache, options, depth = 0)
          cache.fetch(:___routes) { [] } + options.find_all { |pair|
            cache.key?(pair)
          }.flat_map { |pair|
            possibles(cache[pair], options, depth + 1)
          }
        end

        def build_cache
          root = { ___routes: [] }
          routes.routes.each_with_index do |route, i|
            leaf = route.required_defaults.inject(root) do |h, tuple|
              h[tuple] ||= {}
            end
            (leaf[:___routes] ||= []) << [i, route]
          end
          root
        end

        def cache
          @cache ||= build_cache
        end
    end
  end
  # :startdoc:
end