type annotations for DB utils

[nominatim.git] / nominatim / config.py

diff --git a/nominatim/config.py b/nominatim/config.py
index d4645b93b89b08ee0eecab7818f0bc94ce652210..ed7d35e2448e55c9530406a2439b5acdcefedf3b 100644 (file)
--- a/nominatim/config.py
+++ b/nominatim/config.py
@@ -1,15 +1,47 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2022 by the Nominatim developer community.
+# For a full list of authors see the git log.

 """
 Nominatim configuration accessor.
 """
 """
 Nominatim configuration accessor.
 """

+from typing import Dict, Any, List, Mapping, Optional, Union

 import logging
 import os
 from pathlib import Path
 import logging
 import os
 from pathlib import Path

+import json
+import yaml

 
 from dotenv import dotenv_values
 
 from nominatim.errors import UsageError
 
 
 from dotenv import dotenv_values
 
 from nominatim.errors import UsageError
 

+PathOrStr = Union[str, os.PathLike[str]]
+

 LOG = logging.getLogger()
 LOG = logging.getLogger()

+CONFIG_CACHE : Dict[str, Any] = {}
+
+def flatten_config_list(content: Any, section: str = '') -> List[Any]:
+    """ Flatten YAML configuration lists that contain include sections
+        which are lists themselves.
+    """
+    if not content:
+        return []
+
+    if not isinstance(content, list):
+        raise UsageError(f"List expected in section '{section}'.")
+
+    output = []
+    for ele in content:
+        if isinstance(ele, list):
+            output.extend(flatten_config_list(ele, section))
+        else:
+            output.append(ele)
+
+    return output
+

 
 class Configuration:
     """ Load and manage the project configuration.
 
 class Configuration:
     """ Load and manage the project configuration.


@@ -25,51 +57,91 @@ class Configuration:
         avoid conflicts with other environment variables.
     """
 
         avoid conflicts with other environment variables.
     """
 

-    def __init__(self, project_dir, config_dir, environ=None):
+    def __init__(self, project_dir: Path, config_dir: Path,
+                 environ: Optional[Mapping[str, str]] = None) -> None:

         self.environ = environ or os.environ
         self.project_dir = project_dir
         self.config_dir = config_dir
         self._config = dotenv_values(str((config_dir / 'env.defaults').resolve()))
         self.environ = environ or os.environ
         self.project_dir = project_dir
         self.config_dir = config_dir
         self._config = dotenv_values(str((config_dir / 'env.defaults').resolve()))

-        if project_dir is not None:
+        if project_dir is not None and (project_dir / '.env').is_file():

             self._config.update(dotenv_values(str((project_dir / '.env').resolve())))
 
             self._config.update(dotenv_values(str((project_dir / '.env').resolve())))
 

-        # Add defaults for variables that are left empty to set the default.
-        # They may still be overwritten by environment variables.
-        if not self._config['NOMINATIM_ADDRESS_LEVEL_CONFIG']:
-            self._config['NOMINATIM_ADDRESS_LEVEL_CONFIG'] = \
-                str(config_dir / 'address-levels.json')
+        class _LibDirs:
+            pass

 
 

+        self.lib_dir = _LibDirs()

 
 

-    def __getattr__(self, name):
+
+    def set_libdirs(self, **kwargs: PathOrStr) -> None:
+        """ Set paths to library functions and data.
+        """
+        for key, value in kwargs.items():
+            setattr(self.lib_dir, key, Path(value).resolve())
+
+
+    def __getattr__(self, name: str) -> str:

         name = 'NOMINATIM_' + name
 
         name = 'NOMINATIM_' + name
 

-        return self.environ.get(name) or self._config[name]
+        if name in self.environ:
+            return self.environ[name]
+
+        return self._config[name] or ''
+

 
 

-    def get_bool(self, name):
+    def get_bool(self, name: str) -> bool:

         """ Return the given configuration parameter as a boolean.
             Values of '1', 'yes' and 'true' are accepted as truthy values,
             everything else is interpreted as false.
         """
         """ Return the given configuration parameter as a boolean.
             Values of '1', 'yes' and 'true' are accepted as truthy values,
             everything else is interpreted as false.
         """

-        return self.__getattr__(name).lower() in ('1', 'yes', 'true')
+        return getattr(self, name).lower() in ('1', 'yes', 'true')

 
 
 
 

-    def get_int(self, name):
+    def get_int(self, name: str) -> int:

         """ Return the given configuration parameter as an int.
         """
         try:
         """ Return the given configuration parameter as an int.
         """
         try:

-            return int(self.__getattr__(name))
-        except ValueError:
+            return int(getattr(self, name))
+        except ValueError as exp:

             LOG.fatal("Invalid setting NOMINATIM_%s. Needs to be a number.", name)
             LOG.fatal("Invalid setting NOMINATIM_%s. Needs to be a number.", name)

-            raise UsageError("Configuration error.")
+            raise UsageError("Configuration error.") from exp

 
 
 
 

-    def get_libpq_dsn(self):
+    def get_str_list(self, name: str) -> Optional[List[str]]:
+        """ Return the given configuration parameter as a list of strings.
+            The values are assumed to be given as a comma-sparated list and
+            will be stripped before returning them. On empty values None
+            is returned.
+        """
+        raw = getattr(self, name)
+
+        return [v.strip() for v in raw.split(',')] if raw else None
+
+
+    def get_path(self, name: str) -> Optional[Path]:
+        """ Return the given configuration parameter as a Path.
+            If a relative path is configured, then the function converts this
+            into an absolute path with the project directory as root path.
+            If the configuration is unset, None is returned.
+        """
+        value = getattr(self, name)
+        if not value:
+            return None
+
+        cfgpath = Path(value)
+
+        if not cfgpath.is_absolute():
+            cfgpath = self.project_dir / cfgpath
+
+        return cfgpath.resolve()
+
+
+    def get_libpq_dsn(self) -> str:

         """ Get configured database DSN converted into the key/value format
             understood by libpq and psycopg.
         """
         dsn = self.DATABASE_DSN
 
         """ Get configured database DSN converted into the key/value format
             understood by libpq and psycopg.
         """
         dsn = self.DATABASE_DSN
 

-        def quote_param(param):
+        def quote_param(param: str) -> str:

             key, val = param.split('=')
             val = val.replace('\\', '\\\\').replace("'", "\\'")
             if ' ' in val:
             key, val = param.split('=')
             val = val.replace('\\', '\\\\').replace("'", "\\'")
             if ' ' in val:


@@ -83,20 +155,20 @@ class Configuration:
         return dsn
 
 
         return dsn
 
 

-    def get_import_style_file(self):
+    def get_import_style_file(self) -> Path:

         """ Return the import style file as a path object. Translates the
             name of the standard styles automatically into a file in the
             config style.
         """
         """ Return the import style file as a path object. Translates the
             name of the standard styles automatically into a file in the
             config style.
         """

-        style = self.__getattr__('IMPORT_STYLE')
+        style = getattr(self, 'IMPORT_STYLE')

 
         if style in ('admin', 'street', 'address', 'full', 'extratags'):
 
         if style in ('admin', 'street', 'address', 'full', 'extratags'):

-            return self.config_dir / 'import-{}.style'.format(style)
+            return self.config_dir / f'import-{style}.style'

 
 

-        return Path(style)
+        return self.find_config_file('', 'IMPORT_STYLE')

 
 
 
 

-    def get_os_env(self):
+    def get_os_env(self) -> Dict[str, Optional[str]]:

         """ Return a copy of the OS environment with the Nominatim configuration
             merged in.
         """
         """ Return a copy of the OS environment with the Nominatim configuration
             merged in.
         """


@@ -104,3 +176,105 @@ class Configuration:
         env.update(self.environ)
 
         return env
         env.update(self.environ)
 
         return env

+
+
+    def load_sub_configuration(self, filename: PathOrStr,
+                               config: Optional[str] = None) -> Any:
+        """ Load additional configuration from a file. `filename` is the name
+            of the configuration file. The file is first searched in the
+            project directory and then in the global settings dirctory.
+
+            If `config` is set, then the name of the configuration file can
+            be additionally given through a .env configuration option. When
+            the option is set, then the file will be exclusively loaded as set:
+            if the name is an absolute path, the file name is taken as is,
+            if the name is relative, it is taken to be relative to the
+            project directory.
+
+            The format of the file is determined from the filename suffix.
+            Currently only files with extension '.yaml' are supported.
+
+            YAML files support a special '!include' construct. When the
+            directive is given, the value is taken to be a filename, the file
+            is loaded using this function and added at the position in the
+            configuration tree.
+        """
+        configfile = self.find_config_file(filename, config)
+
+        if str(configfile) in CONFIG_CACHE:
+            return CONFIG_CACHE[str(configfile)]
+
+        if configfile.suffix in ('.yaml', '.yml'):
+            result = self._load_from_yaml(configfile)
+        elif configfile.suffix == '.json':
+            with configfile.open('r', encoding='utf-8') as cfg:
+                result = json.load(cfg)
+        else:
+            raise UsageError(f"Config file '{configfile}' has unknown format.")
+
+        CONFIG_CACHE[str(configfile)] = result
+        return result
+
+
+    def find_config_file(self, filename: PathOrStr,
+                         config: Optional[str] = None) -> Path:
+        """ Resolve the location of a configuration file given a filename and
+            an optional configuration option with the file name.
+            Raises a UsageError when the file cannot be found or is not
+            a regular file.
+        """
+        if config is not None:
+            cfg_value = getattr(self, config)
+            if cfg_value:
+                cfg_filename = Path(cfg_value)
+
+                if cfg_filename.is_absolute():
+                    cfg_filename = cfg_filename.resolve()
+
+                    if not cfg_filename.is_file():
+                        LOG.fatal("Cannot find config file '%s'.", cfg_filename)
+                        raise UsageError("Config file not found.")
+
+                    return cfg_filename
+
+                filename = cfg_filename
+
+
+        search_paths = [self.project_dir, self.config_dir]
+        for path in search_paths:
+            if path is not None and (path / filename).is_file():
+                return path / filename
+
+        LOG.fatal("Configuration file '%s' not found.\nDirectories searched: %s",
+                  filename, search_paths)
+        raise UsageError("Config file not found.")
+
+
+    def _load_from_yaml(self, cfgfile: Path) -> Any:
+        """ Load a YAML configuration file. This installs a special handler that
+            allows to include other YAML files using the '!include' operator.
+        """
+        yaml.add_constructor('!include', self._yaml_include_representer,
+                             Loader=yaml.SafeLoader)
+        return yaml.safe_load(cfgfile.read_text(encoding='utf-8'))
+
+
+    def _yaml_include_representer(self, loader: Any, node: yaml.Node) -> Any:
+        """ Handler for the '!include' operator in YAML files.
+
+            When the filename is relative, then the file is first searched in the
+            project directory and then in the global settings dirctory.
+        """
+        fname = loader.construct_scalar(node)
+
+        if Path(fname).is_absolute():
+            configfile = Path(fname)
+        else:
+            configfile = self.find_config_file(loader.construct_scalar(node))
+
+        if configfile.suffix != '.yaml':
+            LOG.fatal("Format error while reading '%s': only YAML format supported.",
+                      configfile)
+            raise UsageError("Cannot handle config file format.")
+
+        return yaml.safe_load(configfile.read_text(encoding='utf-8'))