feat: cached settings resolution at init

djangoldp/conf/settings.py

@@ -21,8 +21,9 @@ def configure(filename='settings.yml'):
     """Helper function to configure django from LDPSettings."""
 
     # ref: https://docs.djangoproject.com/fr/2.2/topics/settings/#custom-default-settings
-    settings = LDPSettings(path=filename)
-    django_settings.configure(settings)     # gives a LazySettings
+    ldpsettings = LDPSettings(path=filename)
+
+    django_settings.configure(ldpsettings)
 
 
 class LDPSettings(object):
@@ -36,6 +37,7 @@ class LDPSettings(object):
 
         self.path = path
         self._config = None
+        self._settings = self.build_settings()
 
     @property
     def config(self):
@@ -65,12 +67,12 @@ class LDPSettings(object):
                 # import from an installed package
                 mod = import_module(f'{pkg}.djangoldp_settings')
                 logger.debug(f'Settings found for {pkg} in a installed package')
-            except (ModuleNotFoundError):
+            except ModuleNotFoundError:
                 try:
                     # import from a local packages in a subfolder (same name the template is built this way)
                     mod = import_module(f'{pkg}.{pkg}.djangoldp_settings')
                     logger.debug(f'Settings found for {pkg} in a local package')
-                except (ModuleNotFoundError):
+                except ModuleNotFoundError:
                     logger.debug(f'No settings found for {pkg}')
                     break
 
@@ -78,12 +80,64 @@ class LDPSettings(object):
             try:
                 attr.extend(getattr(mod, attributes))
                 logger.debug(f'{attributes} found in local package {pkg}')
-            except (NameError):
+            except NameError:
                 logger.info(f'No {attributes} found for package {pkg}')
                 pass
 
         return attr
 
+    def build_settings(self):
+        """
+        Look for the parameter in config. Each step override the value of the previous key found.
+
+        Resolution order of the configuration:
+          1. Core default settings
+          2. Packages settings
+          3. Code from a local settings.py file
+          4. YAML config file
+        """
+
+        # start from default core settings
+        settings = global_settings.__dict__
+        logger.debug(f'building settings from core defaults')
+
+        # look settings from packages in the order they are given (local override installed)
+        for pkg in self.DJANGOLDP_PACKAGES:
+
+            try:
+                # override with values from installed package
+                mod = import_module(f'{pkg}.djangoldp_settings')
+                settings.update({k: v for k, v in mod.__dict__.items() if not k.startswith('_')})
+                logger.debug(f'updating settings from installed package {pkg}')
+            except ModuleNotFoundError:
+                pass
+
+            try:
+                # override with values from local package
+                mod = import_module(f'{pkg}.{pkg}.djangoldp_settings')
+                settings.update({k: v for k, v in mod.__dict__.items() if not k.startswith('_')})
+                logger.debug(f'updating settings from local package {pkg}')
+            except ModuleNotFoundError:
+                pass
+
+        # look in settings.py file in directory
+        try:
+            mod = import_module('settings')
+            settings.update({k: v for k, v in mod.__dict__.items() if not k.startswith('_')})
+            logger.debug(f'updating settings from local settings.py file')
+        except ModuleNotFoundError:
+            pass
+
+        # look in YAML config file 'server' section
+        try:
+            conf = self.config.get('server', {})
+            settings.update({k: v for k, v in conf.items() if not k.startswith('_')})
+            logger.debug(f'updating settings with project config')
+        except KeyError:
+            pass
+
+        return settings
+
     @property
     def DJANGOLDP_PACKAGES(self):
 
@@ -124,54 +178,10 @@ class LDPSettings(object):
         return middlewares
 
     def __getattr__(self, param):
-
-        """
-        Look for the parameter in config and return the first value found.
-
-        Resolution order of the configuration:
-          1. YAML config file
-          2. Packages settings
-          3. Core default settings
-        """
-
-        if not param.startswith('_') and param.isupper():
-
-            # look in config file
-            try:
-                value = self.config['server'][param]
-                logger.debug(f'{param} found in project config')
-                return value
-            except KeyError:
-                pass
-
-            # look in all packages config
-            for pkg in self.DJANGOLDP_PACKAGES:
-
-                try:
-                    # import from local package
-                    mod = import_module(f'{pkg}.{pkg}.djangoldp_settings')
-                    value = getattr(mod, param)
-                    logger.debug(f'{param} found in local package {pkg}')
-                    return value
-                except (ModuleNotFoundError, NameError, AttributeError):
-                    pass
-
-                try:
-                    # import from installed package
-                    mod = import_module(f'{pkg}.djangoldp_settings')
-                    value = getattr(mod, param)
-                    logger.debug(f'{param} found in installed package {pkg}')
-                    return value
-                except (ModuleNotFoundError, NameError, AttributeError):
-                    pass
-
-            # look in default settings
-            try:
-                value = getattr(global_settings, param)
-                logger.debug(f'{param} found in core default config')
-                return value
-            except AttributeError:
-                pass
-
+        """Return the requested parameter from cached settings."""
+        try:
+            return self._settings[param]
+        except KeyError:
             # raise the django exception for inexistent parameter
             raise AttributeError(f'no "{param}" parameter found in settings')
+