Source Code for Package django.conf

  1  """ 
  2  Settings and configuration for Django. 
  3   
  4  Values will be read from the module specified by the DJANGO_SETTINGS_MODULE environment 
  5  variable, and then from django.conf.global_settings; see the global settings file for 
  6  a list of all possible variables. 
  7  """ 
  8   
  9  import os 
 10  import time     # Needed for Windows 
 11  from django.conf import global_settings 
 12   
 13  ENVIRONMENT_VARIABLE = "DJANGO_SETTINGS_MODULE" 
 14   
 15 -class LazySettings(object): 
 16      """ 
 17      A lazy proxy for either global Django settings or a custom settings object. 
 18      The user can manually configure settings prior to using them. Otherwise, 
 19      Django uses the settings module pointed to by DJANGO_SETTINGS_MODULE. 
 20      """ 
 21 -    def __init__(self): 
 22          # _target must be either None or something that supports attribute 
 23          # access (getattr, hasattr, etc). 
 24          self._target = None 
 25   
 26 -    def __getattr__(self, name): 
 27          if self._target is None: 
 28              self._import_settings() 
 29          if name == '__members__': 
 30              # Used to implement dir(obj), for example. 
 31              return self._target.get_all_members() 
 32          return getattr(self._target, name) 
 33   
 34 -    def __setattr__(self, name, value): 
 35          if name == '_target': 
 36              # Assign directly to self.__dict__, because otherwise we'd call 
 37              # __setattr__(), which would be an infinite loop. 
 38              self.__dict__['_target'] = value 
 39          else: 
 40              if self._target is None: 
 41                  self._import_settings() 
 42              setattr(self._target, name, value) 
 43   
 44 -    def _import_settings(self): 
 45          """ 
 46          Load the settings module pointed to by the environment variable. This 
 47          is used the first time we need any settings at all, if the user has not 
 48          previously configured the settings manually. 
 49          """ 
 50          try: 
 51              settings_module = os.environ[ENVIRONMENT_VARIABLE] 
 52              if not settings_module: # If it's set but is an empty string. 
 53                  raise KeyError 
 54          except KeyError: 
 55              raise ImportError, "Environment variable %s is undefined so settings cannot be imported." % ENVIRONMENT_VARIABLE   # NOTE: This is arguably an EnvironmentError, but that causes problems with Python's interactive help 
 56   
 57          self._target = Settings(settings_module) 
 58   
 59 -    def configure(self, default_settings=global_settings, **options): 
 60          """ 
 61          Called to manually configure the settings. The 'default_settings' 
 62          parameter sets where to retrieve any unspecified values from (its 
 63          argument must support attribute access (__getattr__)). 
 64          """ 
 65          if self._target != None: 
 66              raise RuntimeError, 'Settings already configured.' 
 67          holder = UserSettingsHolder(default_settings) 
 68          for name, value in options.items(): 
 69              setattr(holder, name, value) 
 70          self._target = holder 
 71   
 72 -class Settings(object): 
 73 -    def __init__(self, settings_module): 
 74          # update this dict from global settings (but only for ALL_CAPS settings) 
 75          for setting in dir(global_settings): 
 76              if setting == setting.upper(): 
 77                  setattr(self, setting, getattr(global_settings, setting)) 
 78   
 79          # store the settings module in case someone later cares 
 80          self.SETTINGS_MODULE = settings_module 
 81   
 82          try: 
 83              mod = __import__(self.SETTINGS_MODULE, {}, {}, ['']) 
 84          except ImportError, e: 
 85              raise ImportError, "Could not import settings '%s' (Is it on sys.path? Does it have syntax errors?): %s" % (self.SETTINGS_MODULE, e) 
 86   
 87          # Settings that should be converted into tuples if they're mistakenly entered 
 88          # as strings. 
 89          tuple_settings = ("INSTALLED_APPS", "TEMPLATE_DIRS") 
 90   
 91          for setting in dir(mod): 
 92              if setting == setting.upper(): 
 93                  setting_value = getattr(mod, setting) 
 94                  if setting in tuple_settings and type(setting_value) == str: 
 95                      setting_value = (setting_value,) # In case the user forgot the comma. 
 96                  setattr(self, setting, setting_value) 
 97   
 98          # Expand entries in INSTALLED_APPS like "django.contrib.*" to a list 
 99          # of all those apps. 
100          new_installed_apps = [] 
101          for app in self.INSTALLED_APPS: 
102              if app.endswith('.*'): 
103                  appdir = os.path.dirname(__import__(app[:-2], {}, {}, ['']).__file__) 
104                  for d in os.listdir(appdir): 
105                      if d.isalpha() and os.path.isdir(os.path.join(appdir, d)): 
106                          new_installed_apps.append('%s.%s' % (app[:-2], d)) 
107              else: 
108                  new_installed_apps.append(app) 
109          self.INSTALLED_APPS = new_installed_apps 
110   
111          if hasattr(time, 'tzset'): 
112              # Move the time zone info into os.environ. See ticket #2315 for why 
113              # we don't do this unconditionally (breaks Windows). 
114              os.environ['TZ'] = self.TIME_ZONE 
115              time.tzset() 
116   
117 -    def get_all_members(self): 
118          return dir(self) 
119   
120 -class UserSettingsHolder(object): 
121      """ 
122      Holder for user configured settings. 
123      """ 
124      # SETTINGS_MODULE doesn't make much sense in the manually configured 
125      # (standalone) case. 
126      SETTINGS_MODULE = None 
127   
128 -    def __init__(self, default_settings): 
129          """ 
130          Requests for configuration variables not in this class are satisfied 
131          from the module specified in default_settings (if possible). 
132          """ 
133          self.default_settings = default_settings 
134   
135 -    def __getattr__(self, name): 
136          return getattr(self.default_settings, name) 
137   
138 -    def get_all_members(self): 
139          return dir(self) + dir(self.default_settings) 
140   
141  settings = LazySettings() 
142