chrome/common/extensions/docs/server2/api_data_source.py

   1 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 from copy import copy
   6 import logging
   7 import os
   8 import posixpath
   9
  10 from data_source import DataSource
  11 from environment import IsPreviewServer
  12 from extensions_paths import JSON_TEMPLATES, PRIVATE_TEMPLATES
  13 from file_system import FileNotFoundError
  14 from future import Future, Collect
  15 import third_party.json_schema_compiler.json_parse as json_parse
  16 import third_party.json_schema_compiler.model as model
  17 from environment import IsPreviewServer
  18 from third_party.json_schema_compiler.memoize import memoize
  19
  20
  21 def _CreateId(node, prefix):
  22   if node.parent is not None and not isinstance(node.parent, model.Namespace):
  23     return '-'.join([prefix, node.parent.simple_name, node.simple_name])
  24   return '-'.join([prefix, node.simple_name])
  25
  26
  27 def _FormatValue(value):
  28   '''Inserts commas every three digits for integer values. It is magic.
  29   '''
  30   s = str(value)
  31   return ','.join([s[max(0, i - 3):i] for i in range(len(s), 0, -3)][::-1])
  32
  33
  34 def _GetByNameDict(namespace):
  35   '''Returns a dictionary mapping names to named items from |namespace|.
  36
  37   This lets us render specific API entities rather than the whole thing at once,
  38   for example {{apis.manifestTypes.byName.ExternallyConnectable}}.
  39
  40   Includes items from namespace['types'], namespace['functions'],
  41   namespace['events'], and namespace['properties'].
  42   '''
  43   by_name = {}
  44   for item_type in ('types', 'functions', 'events', 'properties'):
  45     if item_type in namespace:
  46       old_size = len(by_name)
  47       by_name.update(
  48           (item['name'], item) for item in namespace[item_type])
  49       assert len(by_name) == old_size + len(namespace[item_type]), (
  50           'Duplicate name in %r' % namespace)
  51   return by_name
  52
  53
  54 def _GetEventByNameFromEvents(events):
  55   '''Parses the dictionary |events| to find the definitions of members of the
  56   type Event.  Returns a dictionary mapping the name of a member to that
  57   member's definition.
  58   '''
  59   assert 'types' in events, \
  60       'The dictionary |events| must contain the key "types".'
  61   event_list = [t for t in events['types'] if t.get('name') == 'Event']
  62   assert len(event_list) == 1, 'Exactly one type must be called "Event".'
  63   return _GetByNameDict(event_list[0])
  64
  65
  66 class _JSCModel(object):
  67   '''Uses a Model from the JSON Schema Compiler and generates a dict that
  68   a Handlebar template can use for a data source.
  69   '''
  70
  71   def __init__(self,
  72                namespace,
  73                availability_finder,
  74                json_cache,
  75                template_cache,
  76                features_bundle,
  77                event_byname_function):
  78     self._availability_finder = availability_finder
  79     self._api_availabilities = json_cache.GetFromFile(
  80         posixpath.join(JSON_TEMPLATES, 'api_availabilities.json'))
  81     self._intro_tables = json_cache.GetFromFile(
  82         posixpath.join(JSON_TEMPLATES, 'intro_tables.json'))
  83     self._api_features = features_bundle.GetAPIFeatures()
  84     self._template_cache = template_cache
  85     self._event_byname_function = event_byname_function
  86     self._namespace = namespace
  87
  88   def _GetLink(self, link):
  89     ref = link if '.' in link else (self._namespace.name + '.' + link)
  90     return { 'ref': ref, 'text': link, 'name': link }
  91
  92   def ToDict(self):
  93     if self._namespace is None:
  94       return {}
  95     chrome_dot_name = 'chrome.%s' % self._namespace.name
  96     as_dict = {
  97       'name': self._namespace.name,
  98       'namespace': self._namespace.documentation_options.get('namespace',
  99                                                              chrome_dot_name),
 100       'title': self._namespace.documentation_options.get('title',
 101                                                          chrome_dot_name),
 102       'documentationOptions': self._namespace.documentation_options,
 103       'types': self._GenerateTypes(self._namespace.types.values()),
 104       'functions': self._GenerateFunctions(self._namespace.functions),
 105       'events': self._GenerateEvents(self._namespace.events),
 106       'domEvents': self._GenerateDomEvents(self._namespace.events),
 107       'properties': self._GenerateProperties(self._namespace.properties),
 108       'introList': self._GetIntroTableList(),
 109       'channelWarning': self._GetChannelWarning(),
 110     }
 111     if self._namespace.deprecated:
 112       as_dict['deprecated'] = self._namespace.deprecated
 113
 114     as_dict['byName'] = _GetByNameDict(as_dict)
 115     return as_dict
 116
 117   def _GetApiAvailability(self):
 118     return self._availability_finder.GetApiAvailability(self._namespace.name)
 119
 120   def _GetChannelWarning(self):
 121     if not self._IsExperimental():
 122       return { self._GetApiAvailability().channel_info.channel: True }
 123     return None
 124
 125   def _IsExperimental(self):
 126     return self._namespace.name.startswith('experimental')
 127
 128   def _GenerateTypes(self, types):
 129     return [self._GenerateType(t) for t in types]
 130
 131   def _GenerateType(self, type_):
 132     type_dict = {
 133       'name': type_.simple_name,
 134       'description': type_.description,
 135       'properties': self._GenerateProperties(type_.properties),
 136       'functions': self._GenerateFunctions(type_.functions),
 137       'events': self._GenerateEvents(type_.events),
 138       'id': _CreateId(type_, 'type')
 139     }
 140     self._RenderTypeInformation(type_, type_dict)
 141     return type_dict
 142
 143   def _GenerateFunctions(self, functions):
 144     return [self._GenerateFunction(f) for f in functions.values()]
 145
 146   def _GenerateFunction(self, function):
 147     function_dict = {
 148       'name': function.simple_name,
 149       'description': function.description,
 150       'callback': self._GenerateCallback(function.callback),
 151       'parameters': [],
 152       'returns': None,
 153       'id': _CreateId(function, 'method')
 154     }
 155     self._AddCommonProperties(function_dict, function)
 156     if function.returns:
 157       function_dict['returns'] = self._GenerateType(function.returns)
 158     for param in function.params:
 159       function_dict['parameters'].append(self._GenerateProperty(param))
 160     if function.callback is not None:
 161       # Show the callback as an extra parameter.
 162       function_dict['parameters'].append(
 163           self._GenerateCallbackProperty(function.callback))
 164     if len(function_dict['parameters']) > 0:
 165       function_dict['parameters'][-1]['last'] = True
 166     return function_dict
 167
 168   def _GenerateEvents(self, events):
 169     return [self._GenerateEvent(e) for e in events.values()
 170             if not e.supports_dom]
 171
 172   def _GenerateDomEvents(self, events):
 173     return [self._GenerateEvent(e) for e in events.values()
 174             if e.supports_dom]
 175
 176   def _GenerateEvent(self, event):
 177     event_dict = {
 178       'name': event.simple_name,
 179       'description': event.description,
 180       'filters': [self._GenerateProperty(f) for f in event.filters],
 181       'conditions': [self._GetLink(condition)
 182                      for condition in event.conditions],
 183       'actions': [self._GetLink(action) for action in event.actions],
 184       'supportsRules': event.supports_rules,
 185       'supportsListeners': event.supports_listeners,
 186       'properties': [],
 187       'id': _CreateId(event, 'event'),
 188       'byName': {},
 189     }
 190     self._AddCommonProperties(event_dict, event)
 191     # Add the Event members to each event in this object.
 192     if self._event_byname_function:
 193       event_dict['byName'].update(self._event_byname_function())
 194     # We need to create the method description for addListener based on the
 195     # information stored in |event|.
 196     if event.supports_listeners:
 197       callback_object = model.Function(parent=event,
 198                                        name='callback',
 199                                        json={},
 200                                        namespace=event.parent,
 201                                        origin='')
 202       callback_object.params = event.params
 203       if event.callback:
 204         callback_object.callback = event.callback
 205       callback_parameters = self._GenerateCallbackProperty(callback_object)
 206       callback_parameters['last'] = True
 207       event_dict['byName']['addListener'] = {
 208         'name': 'addListener',
 209         'callback': self._GenerateFunction(callback_object),
 210         'parameters': [callback_parameters]
 211       }
 212     if event.supports_dom:
 213       # Treat params as properties of the custom Event object associated with
 214       # this DOM Event.
 215       event_dict['properties'] += [self._GenerateProperty(param)
 216                                    for param in event.params]
 217     return event_dict
 218
 219   def _GenerateCallback(self, callback):
 220     if not callback:
 221       return None
 222     callback_dict = {
 223       'name': callback.simple_name,
 224       'simple_type': {'simple_type': 'function'},
 225       'optional': callback.optional,
 226       'parameters': []
 227     }
 228     for param in callback.params:
 229       callback_dict['parameters'].append(self._GenerateProperty(param))
 230     if (len(callback_dict['parameters']) > 0):
 231       callback_dict['parameters'][-1]['last'] = True
 232     return callback_dict
 233
 234   def _GenerateProperties(self, properties):
 235     return [self._GenerateProperty(v) for v in properties.values()]
 236
 237   def _GenerateProperty(self, property_):
 238     if not hasattr(property_, 'type_'):
 239       for d in dir(property_):
 240         if not d.startswith('_'):
 241           print ('%s -> %s' % (d, getattr(property_, d)))
 242     type_ = property_.type_
 243
 244     # Make sure we generate property info for arrays, too.
 245     # TODO(kalman): what about choices?
 246     if type_.property_type == model.PropertyType.ARRAY:
 247       properties = type_.item_type.properties
 248     else:
 249       properties = type_.properties
 250
 251     property_dict = {
 252       'name': property_.simple_name,
 253       'optional': property_.optional,
 254       'description': property_.description,
 255       'properties': self._GenerateProperties(type_.properties),
 256       'functions': self._GenerateFunctions(type_.functions),
 257       'parameters': [],
 258       'returns': None,
 259       'id': _CreateId(property_, 'property')
 260     }
 261     self._AddCommonProperties(property_dict, property_)
 262
 263     if type_.property_type == model.PropertyType.FUNCTION:
 264       function = type_.function
 265       for param in function.params:
 266         property_dict['parameters'].append(self._GenerateProperty(param))
 267       if function.returns:
 268         property_dict['returns'] = self._GenerateType(function.returns)
 269
 270     value = property_.value
 271     if value is not None:
 272       if isinstance(value, int):
 273         property_dict['value'] = _FormatValue(value)
 274       else:
 275         property_dict['value'] = value
 276     else:
 277       self._RenderTypeInformation(type_, property_dict)
 278
 279     return property_dict
 280
 281   def _GenerateCallbackProperty(self, callback):
 282     property_dict = {
 283       'name': callback.simple_name,
 284       'description': callback.description,
 285       'optional': callback.optional,
 286       'is_callback': True,
 287       'id': _CreateId(callback, 'property'),
 288       'simple_type': 'function',
 289     }
 290     if (callback.parent is not None and
 291         not isinstance(callback.parent, model.Namespace)):
 292       property_dict['parentName'] = callback.parent.simple_name
 293     return property_dict
 294
 295   def _RenderTypeInformation(self, type_, dst_dict):
 296     dst_dict['is_object'] = type_.property_type == model.PropertyType.OBJECT
 297     if type_.property_type == model.PropertyType.CHOICES:
 298       dst_dict['choices'] = self._GenerateTypes(type_.choices)
 299       # We keep track of which == last for knowing when to add "or" between
 300       # choices in templates.
 301       if len(dst_dict['choices']) > 0:
 302         dst_dict['choices'][-1]['last'] = True
 303     elif type_.property_type == model.PropertyType.REF:
 304       dst_dict['link'] = self._GetLink(type_.ref_type)
 305     elif type_.property_type == model.PropertyType.ARRAY:
 306       dst_dict['array'] = self._GenerateType(type_.item_type)
 307     elif type_.property_type == model.PropertyType.ENUM:
 308       dst_dict['enum_values'] = [
 309           {'name': value.name, 'description': value.description}
 310           for value in type_.enum_values]
 311       if len(dst_dict['enum_values']) > 0:
 312         dst_dict['enum_values'][-1]['last'] = True
 313     elif type_.instance_of is not None:
 314       dst_dict['simple_type'] = type_.instance_of
 315     else:
 316       dst_dict['simple_type'] = type_.property_type.name
 317
 318   def _GetIntroTableList(self):
 319     '''Create a generic data structure that can be traversed by the templates
 320     to create an API intro table.
 321     '''
 322     intro_rows = [
 323       self._GetIntroDescriptionRow(),
 324       self._GetIntroAvailabilityRow()
 325     ] + self._GetIntroDependencyRows()
 326
 327     # Add rows using data from intro_tables.json, overriding any existing rows
 328     # if they share the same 'title' attribute.
 329     row_titles = [row['title'] for row in intro_rows]
 330     for misc_row in self._GetMiscIntroRows():
 331       if misc_row['title'] in row_titles:
 332         intro_rows[row_titles.index(misc_row['title'])] = misc_row
 333       else:
 334         intro_rows.append(misc_row)
 335
 336     return intro_rows
 337
 338   def _GetIntroDescriptionRow(self):
 339     ''' Generates the 'Description' row data for an API intro table.
 340     '''
 341     return {
 342       'title': 'Description',
 343       'content': [
 344         { 'text': self._namespace.description }
 345       ]
 346     }
 347
 348   def _GetIntroAvailabilityRow(self):
 349     ''' Generates the 'Availability' row data for an API intro table.
 350     '''
 351     if self._IsExperimental():
 352       status = 'experimental'
 353       version = None
 354       scheduled = None
 355     else:
 356       availability = self._GetApiAvailability()
 357       status = availability.channel_info.channel
 358       version = availability.channel_info.version
 359       scheduled = availability.scheduled
 360     return {
 361       'title': 'Availability',
 362       'content': [{
 363         'partial': self._template_cache.GetFromFile(
 364           posixpath.join(PRIVATE_TEMPLATES,
 365                          'intro_tables',
 366                          '%s_message.html' % status)).Get(),
 367         'version': version,
 368         'scheduled': scheduled
 369       }]
 370     }
 371
 372   def _GetIntroDependencyRows(self):
 373     # Devtools aren't in _api_features. If we're dealing with devtools, bail.
 374     if 'devtools' in self._namespace.name:
 375       return []
 376
 377     api_feature = self._api_features.Get().get(self._namespace.name)
 378     if not api_feature:
 379       logging.error('"%s" not found in _api_features.json' %
 380                     self._namespace.name)
 381       return []
 382
 383     permissions_content = []
 384     manifest_content = []
 385
 386     def categorize_dependency(dependency):
 387       def make_code_node(text):
 388         return { 'class': 'code', 'text': text }
 389
 390       context, name = dependency.split(':', 1)
 391       if context == 'permission':
 392         permissions_content.append(make_code_node('"%s"' % name))
 393       elif context == 'manifest':
 394         manifest_content.append(make_code_node('"%s": {...}' % name))
 395       elif context == 'api':
 396         transitive_dependencies = (
 397             self._api_features.Get().get(name, {}).get('dependencies', []))
 398         for transitive_dependency in transitive_dependencies:
 399           categorize_dependency(transitive_dependency)
 400       else:
 401         logging.error('Unrecognized dependency for %s: %s' %
 402                       (self._namespace.name, context))
 403
 404     for dependency in api_feature.get('dependencies', ()):
 405       categorize_dependency(dependency)
 406
 407     dependency_rows = []
 408     if permissions_content:
 409       dependency_rows.append({
 410         'title': 'Permissions',
 411         'content': permissions_content
 412       })
 413     if manifest_content:
 414       dependency_rows.append({
 415         'title': 'Manifest',
 416         'content': manifest_content
 417       })
 418     return dependency_rows
 419
 420   def _GetMiscIntroRows(self):
 421     ''' Generates miscellaneous intro table row data, such as 'Permissions',
 422     'Samples', and 'Learn More', using intro_tables.json.
 423     '''
 424     misc_rows = []
 425     # Look up the API name in intro_tables.json, which is structured
 426     # similarly to the data structure being created. If the name is found, loop
 427     # through the attributes and add them to this structure.
 428     table_info = self._intro_tables.Get().get(self._namespace.name)
 429     if table_info is None:
 430       return misc_rows
 431
 432     for category in table_info.iterkeys():
 433       content = []
 434       for node in table_info[category]:
 435         # If there is a 'partial' argument and it hasn't already been
 436         # converted to a Handlebar object, transform it to a template.
 437         if 'partial' in node:
 438           # Note: it's enough to copy() not deepcopy() because only a single
 439           # top-level key is being modified.
 440           node = copy(node)
 441           node['partial'] = self._template_cache.GetFromFile(
 442               posixpath.join(PRIVATE_TEMPLATES, node['partial'])).Get()
 443         content.append(node)
 444       misc_rows.append({ 'title': category, 'content': content })
 445     return misc_rows
 446
 447   def _AddCommonProperties(self, target, src):
 448     if src.deprecated is not None:
 449       target['deprecated'] = src.deprecated
 450     if (src.parent is not None and
 451         not isinstance(src.parent, model.Namespace)):
 452       target['parentName'] = src.parent.simple_name
 453
 454
 455 class _LazySamplesGetter(object):
 456   '''This class is needed so that an extensions API page does not have to fetch
 457   the apps samples page and vice versa.
 458   '''
 459
 460   def __init__(self, api_name, samples):
 461     self._api_name = api_name
 462     self._samples = samples
 463
 464   def get(self, key):
 465     return self._samples.FilterSamples(key, self._api_name)
 466
 467
 468 class APIDataSource(DataSource):
 469   '''This class fetches and loads JSON APIs from the FileSystem passed in with
 470   |compiled_fs_factory|, so the APIs can be plugged into templates.
 471   '''
 472   def __init__(self, server_instance, request):
 473     file_system = server_instance.host_file_system_provider.GetTrunk()
 474     self._json_cache = server_instance.compiled_fs_factory.ForJson(file_system)
 475     self._template_cache = server_instance.compiled_fs_factory.ForTemplates(
 476         file_system)
 477     self._availability_finder = server_instance.availability_finder
 478     self._api_models = server_instance.api_models
 479     self._features_bundle = server_instance.features_bundle
 480     self._model_cache = server_instance.object_store_creator.Create(
 481         APIDataSource)
 482
 483     # This caches the result of _LoadEventByName.
 484     self._event_byname = None
 485     self._samples = server_instance.samples_data_source_factory.Create(request)
 486
 487   def _LoadEventByName(self):
 488     '''All events have some members in common. We source their description
 489     from Event in events.json.
 490     '''
 491     if self._event_byname is None:
 492       self._event_byname = _GetEventByNameFromEvents(
 493           self._GetSchemaModel('events').Get())
 494     return self._event_byname
 495
 496   def _GetSchemaModel(self, api_name):
 497     jsc_model_future = self._model_cache.Get(api_name)
 498     model_future = self._api_models.GetModel(api_name)
 499     def resolve():
 500       jsc_model = jsc_model_future.Get()
 501       if jsc_model is None:
 502         jsc_model = _JSCModel(
 503             model_future.Get(),
 504             self._availability_finder,
 505             self._json_cache,
 506             self._template_cache,
 507             self._features_bundle,
 508             self._LoadEventByName).ToDict()
 509         self._model_cache.Set(api_name, jsc_model)
 510       return jsc_model
 511     return Future(callback=resolve)
 512
 513   def _GetImpl(self, api_name):
 514     handlebar_dict_future = self._GetSchemaModel(api_name)
 515     def resolve():
 516       handlebar_dict = handlebar_dict_future.Get()
 517       # Parsing samples on the preview server takes seconds and doesn't add
 518       # anything. Don't do it.
 519       if not IsPreviewServer():
 520         handlebar_dict['samples'] = _LazySamplesGetter(
 521             handlebar_dict['name'],
 522             self._samples)
 523       return handlebar_dict
 524     return Future(callback=resolve)
 525
 526   def get(self, api_name):
 527     return self._GetImpl(api_name).Get()
 528
 529   def Cron(self):
 530     futures = [self._GetImpl(name) for name in self._api_models.GetNames()]
 531     return Collect(futures, except_pass=FileNotFoundError)