python/google/appengine/api/pagespeedinfo.py

   1 #!/usr/bin/env python
   2 #
   3 # Copyright 2007 Google Inc.
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #     http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16 #
  17
  18
  19
  20
  21 """PageSpeed configuration tools.
  22
  23 Library for parsing pagespeed configuration data from app.yaml and working
  24 with these in memory.
  25 """
  26
  27
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  30
  31
  32
  33
  34 import google
  35
  36 from google.appengine.api import validation
  37 from google.appengine.api import yaml_builder
  38 from google.appengine.api import yaml_listener
  39 from google.appengine.api import yaml_object
  40
  41 _URL_BLACKLIST_REGEX = r'http(s)?://\S{0,499}'
  42 _REWRITER_NAME_REGEX = r'[a-zA-Z0-9_]+'
  43 _DOMAINS_TO_REWRITE_REGEX = r'(http(s)?://)?[-a-zA-Z0-9_.*]+(:\d+)?'
  44
  45 URL_BLACKLIST = 'url_blacklist'
  46 ENABLED_REWRITERS = 'enabled_rewriters'
  47 DISABLED_REWRITERS = 'disabled_rewriters'
  48 DOMAINS_TO_REWRITE = 'domains_to_rewrite'
  49
  50
  51 class MalformedPagespeedConfiguration(Exception):
  52   """Configuration file for PageSpeed API is malformed."""
  53
  54
  55
  56
  57
  58
  59 class PagespeedEntry(validation.Validated):
  60   """Describes the format of a pagespeed configuration from a yaml file.
  61
  62   URL blacklist entries are patterns (with '?' and '*' as wildcards).  Any URLs
  63   that match a pattern on the blacklist will not be optimized by PageSpeed.
  64
  65   Rewriter names are strings (like 'CombineCss' or 'RemoveComments') describing
  66   individual PageSpeed rewriters.  A full list of valid rewriter names can be
  67   found in the PageSpeed documentation.
  68
  69   The domains-to-rewrite list is a whitelist of domain name patterns with '*' as
  70   a wildcard, optionally starting with 'http://' or 'https://'.  If no protocol
  71   is given, 'http://' is assumed.  A resource will only be rewritten if it is on
  72   the same domain as the HTML that references it, or if its domain is on the
  73   domains-to-rewrite list.
  74   """
  75   ATTRIBUTES = {
  76       URL_BLACKLIST: validation.Optional(
  77           validation.Repeated(validation.Regex(_URL_BLACKLIST_REGEX))),
  78       ENABLED_REWRITERS: validation.Optional(
  79           validation.Repeated(validation.Regex(_REWRITER_NAME_REGEX))),
  80       DISABLED_REWRITERS: validation.Optional(
  81           validation.Repeated(validation.Regex(_REWRITER_NAME_REGEX))),
  82       DOMAINS_TO_REWRITE: validation.Optional(
  83           validation.Repeated(validation.Regex(_DOMAINS_TO_REWRITE_REGEX))),
  84   }
  85
  86
  87 def LoadPagespeedEntry(pagespeed_entry, open_fn=None):
  88   """Load a yaml file or string and return a PagespeedEntry.
  89
  90   Args:
  91     pagespeed_entry: The contents of a pagespeed entry from a yaml file
  92       as a string, or an open file object.
  93     open_fn: Function for opening files. Unused.
  94
  95   Returns:
  96     A PagespeedEntry instance which represents the contents of the parsed yaml.
  97
  98   Raises:
  99     yaml_errors.EventError: An error occured while parsing the yaml.
 100     MalformedPagespeedConfiguration: The configuration is parseable but invalid.
 101   """
 102   builder = yaml_object.ObjectBuilder(PagespeedEntry)
 103   handler = yaml_builder.BuilderHandler(builder)
 104   listener = yaml_listener.EventListener(handler)
 105   listener.Parse(pagespeed_entry)
 106
 107   parsed_yaml = handler.GetResults()
 108   if not parsed_yaml:
 109     return PagespeedEntry()
 110
 111   if len(parsed_yaml) > 1:
 112     raise MalformedPagespeedConfiguration(
 113         'Multiple configuration sections in the yaml')
 114
 115   return parsed_yaml[0]