Class: ActionController::Routing::RouteSet

Inherits:
Object
  • Object
show all
Defined in:
lib/action_controller/routing/route_set.rb,
lib/action_controller/routing/recognition_optimisation.rb

Overview

BEFORE: 0.191446860631307 ms/url AFTER: 0.029847304022858 ms/url Speed up: 6.4 times

Route recognition is slow due to one-by-one iterating over a whole routeset (each map.resources generates at least 14 routes) and matching weird regexps on each step.

We optimize this by skipping all URI segments that 100% sure can’t be matched, moving deeper in a tree of routes (where node == segment) until first possible match is accured. In such case, we start walking a flat list of routes, matching them with accurate matcher. So, first step: search a segment tree for the first relevant index. Second step: iterate routes starting with that index.

How tree is walked? We can do a recursive tests, but it’s smarter: We just create a tree of if-s and elsif-s matching segments.

We have segments of 3 flavors: 1) nil (no segment, route finished) 2) const-dot-dynamic (like “/posts.:xml”, “/preview.:size.jpg”) 3) const (like “/posts”, “/comments”) 4) dynamic (“/:id”, “file.:size.:extension”)

We split incoming string into segments and iterate over them. When segment is nil, we drop immediately, on a current node index. When segment is equal to some const, we step into branch. If none constants matched, we step into ‘dynamic’ branch (it’s a last). If we can’t match anything, we drop to last index on a level.

Note: we maintain the original routes order, so we finish building

steps on a first dynamic segment.

Example. Given the routes:

0 /posts/
1 /posts/:id
2 /posts/:id/comments
3 /posts/blah
4 /users/
5 /users/:id
6 /users/:id/profile

request_uri = /users/123

There will be only 4 iterations:

1) segm test for /posts prefix, skip all /posts/* routes
2) segm test for /users/
3) segm test for /users/:id
   (jump to list index = 5)
4) full test for /users/:id => here we are!

Defined Under Namespace

Classes: Mapper, NamedRouteCollection

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ RouteSet

Returns a new instance of RouteSet.



194
195
196
197
198
 
# File 'lib/action_controller/routing/route_set.rb', line 194

def initialize
  self.routes = []
  self.named_routes = NamedRouteCollection.new
  clear_recognize_optimized!
end

Instance Attribute Details

#configuration_file ⇒ Object

Returns the value of attribute configuration_file.



192
193
194
 
# File 'lib/action_controller/routing/route_set.rb', line 192

def configuration_file
  @configuration_file
end

#named_routes ⇒ Object

Returns the value of attribute named_routes.



192
193
194
 
# File 'lib/action_controller/routing/route_set.rb', line 192

def named_routes
  @named_routes
end

#routes ⇒ Object

Returns the value of attribute routes.



192
193
194
 
# File 'lib/action_controller/routing/route_set.rb', line 192

def routes
  @routes
end

Instance Method Details

#add_named_route(name, path, options = {}) ⇒ Object 



267
268
269
270
271
 
# File 'lib/action_controller/routing/route_set.rb', line 267

def add_named_route(name, path, options = {})
  # TODO - is options EVER used?
  name = options[:name_prefix] + name.to_s if options[:name_prefix]
  named_routes[name.to_sym] = add_route(path, options)
end

#add_route(path, options = {}) ⇒ Object 



261
262
263
264
265
 
# File 'lib/action_controller/routing/route_set.rb', line 261

def add_route(path, options = {})
  route = builder.build(path, options)
  routes << route
  route
end

#build_expiry(options, recall) ⇒ Object 



291
292
293
294
295
296
 
# File 'lib/action_controller/routing/route_set.rb', line 291

def build_expiry(options, recall)
  recall.inject({}) do |expiry, (key, recalled_value)|
    expiry[key] = (options.key?(key) && options[key].to_param != recalled_value.to_param)
    expiry
  end
end

#builder ⇒ Object

Subclasses and plugins may override this method to specify a different RouteBuilder instance, so that other route DSL’s can be created.



202
203
204
 
# File 'lib/action_controller/routing/route_set.rb', line 202

def builder
  @builder ||= RouteBuilder.new
end

#clear! ⇒ Object 



212
213
214
215
216
217
218
219
220
 
# File 'lib/action_controller/routing/route_set.rb', line 212

def clear!
  routes.clear
  named_routes.clear
  @combined_regexp = nil
  @routes_by_controller = nil
  # This will force routing/recognition_optimisation.rb
  # to refresh optimisations.
  clear_recognize_optimized!
end

#clear_recognize_optimized! ⇒ Object 



71
72
73
74
75
76
77
78
 
# File 'lib/action_controller/routing/recognition_optimisation.rb', line 71

def clear_recognize_optimized!
  instance_eval %{
    def recognize_optimized(path, env)
      write_recognize_optimized!
      recognize_optimized(path, env)
    end
  }, __FILE__, __LINE__
end

#draw {|Mapper.new(self)| ... } ⇒ Object

Yields:



206
207
208
209
210
 
# File 'lib/action_controller/routing/route_set.rb', line 206

def draw
  clear!
  yield Mapper.new(self)
  install_helpers
end

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


227
228
229
 
# File 'lib/action_controller/routing/route_set.rb', line 227

def empty?
  routes.empty?
end

#extra_keys(options, recall = {}) ⇒ Object

Generate the path indicated by the arguments, and return an array of the keys that were not used to generate it.



300
301
302
 
# File 'lib/action_controller/routing/route_set.rb', line 300

def extra_keys(options, recall={})
  generate_extras(options, recall).last
end

#extract_request_environment(request) ⇒ Object

Subclasses and plugins may override this method to extract further attributes from the request, for use by route conditions and such.



431
432
433
 
# File 'lib/action_controller/routing/route_set.rb', line 431

def extract_request_environment(request)
  { :method => request.method }
end

#generate(options, recall = {}, method = :generate) ⇒ Object

Raises:



308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
 
# File 'lib/action_controller/routing/route_set.rb', line 308

def generate(options, recall = {}, method=:generate)
  named_route_name = options.delete(:use_route)
  generate_all = options.delete(:generate_all)
  if named_route_name
    named_route = named_routes[named_route_name]
    options = named_route.parameter_shell.merge(options)
  end

  options = options_as_params(options)
  expire_on = build_expiry(options, recall)

  if options[:controller]
    options[:controller] = options[:controller].to_s
  end
  # if the controller has changed, make sure it changes relative to the
  # current controller module, if any. In other words, if we're currently
  # on admin/get, and the new controller is 'set', the new controller
  # should really be admin/set.
  if !named_route && expire_on[:controller] && options[:controller] && options[:controller][0] != ?/
    old_parts = recall[:controller].split('/')
    new_parts = options[:controller].split('/')
    parts = old_parts[0..-(new_parts.length + 1)] + new_parts
    options[:controller] = parts.join('/')
  end

  # drop the leading '/' on the controller name
  options[:controller] = options[:controller][1..-1] if options[:controller] && options[:controller][0] == ?/
  merged = recall.merge(options)

  if named_route
    path = named_route.generate(options, merged, expire_on)
    if path.nil?
      raise_named_route_error(options, named_route, named_route_name)
    else
      return path
    end
  else
    merged[:action] ||= 'index'
    options[:action] ||= 'index'

    controller = merged[:controller]
    action = merged[:action]

    raise RoutingError, "Need controller and action!" unless controller && action

    if generate_all
      # Used by caching to expire all paths for a resource
      return routes.collect do |route|
        route.send!(method, options, merged, expire_on)
      end.compact
    end

    # don't use the recalled keys when determining which routes to check
    routes = routes_by_controller[controller][action][options.keys.sort_by { |x| x.object_id }]

    routes.each do |route|
      results = route.send!(method, options, merged, expire_on)
      return results if results && (!results.is_a?(Array) || results.first)
    end
  end

  raise RoutingError, "No route matches #{options.inspect}"
end

#generate_code(list, padding = ' ', level = 0) ⇒ Object 



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
 
# File 'lib/action_controller/routing/recognition_optimisation.rb', line 116

def generate_code(list, padding='  ', level = 0)
  # a digit
  return padding + "#{list[0]}\n" if list.size == 1 && !(Array === list[0])

  body = padding + "(seg = segments[#{level}]; \n"

  i = 0
  was_nil = false
  list.each do |item|
    if Array === item
      i += 1
      start = (i == 1)
      final = (i == list.size)
      tag, sub = item
      if tag == :dynamic
        body += padding + "#{start ? 'if' : 'elsif'} true\n"
        body += generate_code(sub, padding + "  ", level + 1)
        break
      elsif tag == nil && !was_nil
        was_nil = true
        body += padding + "#{start ? 'if' : 'elsif'} seg.nil?\n"
        body += generate_code(sub, padding + "  ", level + 1)
      else
        body += padding + "#{start ? 'if' : 'elsif'} seg == '#{tag}'\n"
        body += generate_code(sub, padding + "  ", level + 1)
      end
    end
  end
  body += padding + "else\n"
  body += padding + "  #{list[0]}\n"
  body += padding + "end)\n"
  body
end

#generate_extras(options, recall = {}) ⇒ Object 



304
305
306
 
# File 'lib/action_controller/routing/route_set.rb', line 304

def generate_extras(options, recall={})
  generate(options, recall, :generate_extras)
end

#install_helpers(destinations = [ActionController::Base, ActionView::Base], regenerate_code = false) ⇒ Object 



222
223
224
225
 
# File 'lib/action_controller/routing/route_set.rb', line 222

def install_helpers(destinations = [ActionController::Base, ActionView::Base], regenerate_code = false)
  Array(destinations).each { |d| d.module_eval { include Helpers } }
  named_routes.install(destinations, regenerate_code)
end

#load! ⇒ Object Also known as: reload! 



231
232
233
234
235
236
 
# File 'lib/action_controller/routing/route_set.rb', line 231

def load!
  Routing.use_controllers! nil # Clear the controller cache so we may discover new ones
  clear!
  load_routes!
  install_helpers
end

#load_routes! ⇒ Object 



252
253
254
255
256
257
258
259
 
# File 'lib/action_controller/routing/route_set.rb', line 252

def load_routes!
  if configuration_file
    load configuration_file
    @routes_last_modified = File.stat(configuration_file).mtime
  else
    add_route ":controller/:action/:id"
  end
end

#options_as_params(options) ⇒ Object 



273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
 
# File 'lib/action_controller/routing/route_set.rb', line 273

def options_as_params(options)
  # If an explicit :controller was given, always make :action explicit
  # too, so that action expiry works as expected for things like
  #
  #   generate({:controller => 'content'}, {:controller => 'content', :action => 'show'})
  #
  # (the above is from the unit tests). In the above case, because the
  # controller was explicitly given, but no action, the action is implied to
  # be "index", not the recalled action of "show".
  #
  # great fun, eh?

  options_as_params = options.clone
  options_as_params[:action] ||= 'index' if options[:controller]
  options_as_params[:action] = options_as_params[:action].to_s if options_as_params[:action]
  options_as_params
end

#raise_named_route_error(options, named_route, named_route_name) ⇒ Object

try to give a helpful error message when named route generation fails



373
374
375
376
377
378
379
380
381
382
 
# File 'lib/action_controller/routing/route_set.rb', line 373

def raise_named_route_error(options, named_route, named_route_name)
  diff = named_route.requirements.diff(options)
  unless diff.empty?
    raise RoutingError, "#{named_route_name}_url failed to generate from #{options.inspect}, expected: #{named_route.requirements.inspect}, diff: #{named_route.requirements.diff(options).inspect}"
  else
    required_segments = named_route.segments.select {|seg| (!seg.optional?) && (!seg.is_a?(DividerSegment)) }
    required_keys_or_values = required_segments.map { |seg| seg.key rescue seg.value } # we want either the key or the value from the segment
    raise RoutingError, "#{named_route_name}_url failed to generate from #{options.inspect} - you may have ambiguous routes, or you may need to supply additional parameters for this route.  content_url has the following required parameters: #{required_keys_or_values.inspect} - are they all satisfied?"
  end
end

#recognize(request) ⇒ Object 



384
385
386
387
388
 
# File 'lib/action_controller/routing/route_set.rb', line 384

def recognize(request)
  params = recognize_path(request.path, extract_request_environment(request))
  request.path_parameters = params.with_indifferent_access
  "#{params[:controller].camelize}Controller".constantize
end

#recognize_path(path, environment = {}) ⇒ Object 



390
391
392
 
# File 'lib/action_controller/routing/route_set.rb', line 390

def recognize_path(path, environment={})
  raise "Not optimized! Check that routing/recognition_optimisation overrides RouteSet#recognize_path."
end

#reload ⇒ Object 



241
242
243
244
245
246
247
248
249
250
 
# File 'lib/action_controller/routing/route_set.rb', line 241

def reload
  if @routes_last_modified && configuration_file
    mtime = File.stat(configuration_file).mtime
    # if it hasn't been changed, then just return
    return if mtime == @routes_last_modified
    # if it has changed then record the new time and fall to the load! below
    @routes_last_modified = mtime
  end
  load!
end

#routes_by_controller ⇒ Object 



394
395
396
397
398
399
400
401
402
 
# File 'lib/action_controller/routing/route_set.rb', line 394

def routes_by_controller
  @routes_by_controller ||= Hash.new do |controller_hash, controller|
    controller_hash[controller] = Hash.new do |action_hash, action|
      action_hash[action] = Hash.new do |key_hash, keys|
        key_hash[keys] = routes_for_controller_and_action_and_keys(controller, action, keys)
      end
    end
  end
end

#routes_for(options, merged, expire_on) ⇒ Object 



404
405
406
407
408
409
410
411
 
# File 'lib/action_controller/routing/route_set.rb', line 404

def routes_for(options, merged, expire_on)
  raise "Need controller and action!" unless controller && action
  controller = merged[:controller]
  merged = options if expire_on[:controller]
  action = merged[:action] || 'index'

  routes_by_controller[controller][action][merged.keys]
end

#routes_for_controller_and_action(controller, action) ⇒ Object 



413
414
415
416
417
418
 
# File 'lib/action_controller/routing/route_set.rb', line 413

def routes_for_controller_and_action(controller, action)
  selected = routes.select do |route|
    route.matches_controller_and_action? controller, action
  end
  (selected.length == routes.length) ? routes : selected
end

#routes_for_controller_and_action_and_keys(controller, action, keys) ⇒ Object 



420
421
422
423
424
425
426
427
 
# File 'lib/action_controller/routing/route_set.rb', line 420

def routes_for_controller_and_action_and_keys(controller, action, keys)
  selected = routes.select do |route|
    route.matches_controller_and_action? controller, action
  end
  selected.sort_by do |route|
    (keys - route.significant_keys).length
  end
end

#segment_tree(routes) ⇒ Object 



97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
 
# File 'lib/action_controller/routing/recognition_optimisation.rb', line 97

def segment_tree(routes)
  tree = [0]

  i = -1
  routes.each do |route|
    i += 1
    # not fast, but runs only once
    segments = to_plain_segments(route.segments.inject("") { |str,s| str << s.to_s })

    node  = tree
    segments.each do |seg|
      seg = :dynamic if seg && seg[0] == ?:
      node << [seg, [i]] if node.empty? || node[node.size - 1][0] != seg
      node = node[node.size - 1][1]
    end
  end
  tree
end

#to_plain_segments(str) ⇒ Object

this must be really fast



151
152
153
154
155
156
157
158
 
# File 'lib/action_controller/routing/recognition_optimisation.rb', line 151

def to_plain_segments(str)
  str = str.dup
  str.sub!(/^\/+/,'')
  str.sub!(/\/+$/,'')
  segments = str.split(/\.[^\/]+\/+|\/+|\.[^\/]+\Z/) # cut off ".format" also
  segments << nil
  segments
end

#write_recognize_optimized! ⇒ Object 



80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
 
# File 'lib/action_controller/routing/recognition_optimisation.rb', line 80

def write_recognize_optimized!
  tree = segment_tree(routes)
  body = generate_code(tree)
  instance_eval %{
    def recognize_optimized(path, env)
      segments = to_plain_segments(path)
      index = #{body}
      return nil unless index
      while index < routes.size
        result = routes[index].recognize(path, env) and return result
        index += 1
      end
      nil
    end
  }, __FILE__, __LINE__
end