CLI: get valid --format values via autodiscover

[nominatim.git] / nominatim / config.py

diff --git a/nominatim/config.py b/nominatim/config.py
index 4fa887a1d10e84baefa5721ae28500a703dda7b3..3344a425a5667d58f6e2cd79e916f0b9bbb8c839 100644 (file)
--- a/nominatim/config.py
+++ b/nominatim/config.py
@@ -1,39 +1,374 @@
+# 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.
 """

-import sys
+from typing import Dict, Any, List, Mapping, Optional
+import importlib.util
+import logging

 import os
 import os

+import sys
+from pathlib import Path
+import json
+import yaml

 
 from dotenv import dotenv_values
 
 from dotenv import dotenv_values

+from psycopg2.extensions import parse_dsn

 
 

-class Configuration:
-    """ Load and manage the project configuration.
+from nominatim.typing import StrPath
+from nominatim.errors import UsageError
+import nominatim.paths
+
+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}'.")

 
 

-        Nominatim uses dotenv to configure the software. Configuration options
-        are resolved in the following order:
+    output = []
+    for ele in content:
+        if isinstance(ele, list):
+            output.extend(flatten_config_list(ele, section))
+        else:
+            output.append(ele)

 
 

-         * from the OS environment
-         * from the .env file in the project directory of the installation
-         * from the default installation in the configuration directory
+    return output
+
+
+class Configuration:
+    """ This class wraps access to the configuration settings
+        for the Nominatim instance in use.

 
         All Nominatim configuration options are prefixed with 'NOMINATIM_' to
 
         All Nominatim configuration options are prefixed with 'NOMINATIM_' to

-        avoid conflicts with other environment variables.
+        avoid conflicts with other environment variables. All settings can
+        be accessed as properties of the class under the same name as the
+        setting but with the `NOMINATIM_` prefix removed. In addition, there
+        are accessor functions that convert the setting values to types
+        other than string.

     """
 
     """
 

-    def __init__(self, project_dir, config_dir):
-        self._config = dotenv_values(str((config_dir / 'env.defaults').resolve()))
-        self._config.update(dotenv_values(str((project_dir / '.env').resolve())))
+    def __init__(self, project_dir: Optional[Path],
+                 environ: Optional[Mapping[str, str]] = None) -> None:
+        self.environ = environ or os.environ
+        self.project_dir = project_dir
+        self.config_dir = nominatim.paths.CONFIG_DIR
+        self._config = dotenv_values(str(self.config_dir / 'env.defaults'))
+        if self.project_dir is not None and (self.project_dir / '.env').is_file():
+            self.project_dir = self.project_dir.resolve()
+            self._config.update(dotenv_values(str(self.project_dir / '.env')))
+
+        class _LibDirs:
+            module: Path
+            osm2pgsql: Path
+            php = nominatim.paths.PHPLIB_DIR
+            sql = nominatim.paths.SQLLIB_DIR
+            data = nominatim.paths.DATA_DIR
+
+        self.lib_dir = _LibDirs()
+        self._private_plugins: Dict[str, object] = {}
+

 
 

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

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

-        return os.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: str) -> bool:
+        """ Return the given configuration parameter as a boolean.
+
+            Parameters:
+              name: Name of the configuration parameter with the NOMINATIM_
+                prefix removed.
+
+            Returns:
+              `True` for values of '1', 'yes' and 'true', `False` otherwise.
+        """
+        return getattr(self, name).lower() in ('1', 'yes', 'true')
+
+
+    def get_int(self, name: str) -> int:
+        """ Return the given configuration parameter as an int.
+
+            Parameters:
+              name: Name of the configuration parameter with the NOMINATIM_
+                prefix removed.
+
+            Returns:
+              The configuration value converted to int.
+
+            Raises:
+              ValueError: when the value is not a number.
+        """
+        try:
+            return int(getattr(self, name))
+        except ValueError as exp:
+            LOG.fatal("Invalid setting NOMINATIM_%s. Needs to be a number.", name)
+            raise UsageError("Configuration error.") from exp
+
+
+    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. 
+
+            Parameters:
+              name: Name of the configuration parameter with the NOMINATIM_
+                prefix removed.
+
+            Returns:
+              (List[str]): The comma-split parameter as a list. The
+                elements are stripped of leading and final spaces before
+                being returned.
+              (None): The configuration parameter was unset or empty.
+        """
+        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.
+
+            Parameters:
+              name: Name of the configuration parameter with the NOMINATIM_
+                prefix removed.
+
+            Returns:
+              (Path): A Path object of the parameter value.
+                  If a relative path is configured, then the function converts this
+                  into an absolute path with the project directory as root path.
+              (None): The configuration parameter was unset or empty.
+        """
+        value = getattr(self, name)
+        if not value:
+            return None
+
+        cfgpath = Path(value)
+
+        if not cfgpath.is_absolute():
+            assert self.project_dir is not None
+            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
+
+        def quote_param(param: str) -> str:
+            key, val = param.split('=')
+            val = val.replace('\\', '\\\\').replace("'", "\\'")
+            if ' ' in val:
+                val = "'" + val + "'"
+            return key + '=' + val
+
+        if dsn.startswith('pgsql:'):
+            # Old PHP DSN format. Convert before returning.
+            return ' '.join([quote_param(p) for p in dsn[6:].split(';')])
+
+        return dsn
+
+
+    def get_database_params(self) -> Mapping[str, str]:
+        """ Get the configured parameters for the database connection
+            as a mapping.
+        """
+        dsn = self.DATABASE_DSN
+
+        if dsn.startswith('pgsql:'):
+            return dict((p.split('=', 1) for p in dsn[6:].split(';')))
+
+        return parse_dsn(dsn)
+
+
+    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.
+        """
+        style = getattr(self, 'IMPORT_STYLE')
+
+        if style in ('admin', 'street', 'address', 'full', 'extratags'):
+            return self.config_dir / f'import-{style}.lua'

 
 

-    def get_os_env(self):
+        return self.find_config_file('', 'IMPORT_STYLE')
+
+
+    def get_os_env(self) -> Dict[str, 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.
         """

-        env = dict(os.environ)
-        env.update(self._config)
+        env = {k: v for k, v in self._config.items() if v is not None}
+        env.update(self.environ)

 
         return env
 
         return env

+
+
+    def load_sub_configuration(self, filename: StrPath,
+                               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 directory.
+
+            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 load_plugin_module(self, module_name: str, internal_path: str) -> Any:
+        """ Load a Python module as a plugin.
+
+            The module_name may have three variants:
+
+            * A name without any '.' is assumed to be an internal module
+              and will be searched relative to `internal_path`.
+            * If the name ends in `.py`, module_name is assumed to be a
+              file name relative to the project directory.
+            * Any other name is assumed to be an absolute module name.
+
+            In either of the variants the module name must start with a letter.
+        """
+        if not module_name or not module_name[0].isidentifier():
+            raise UsageError(f'Invalid module name {module_name}')
+
+        if '.' not in module_name:
+            module_name = module_name.replace('-', '_')
+            full_module = f'{internal_path}.{module_name}'
+            return sys.modules.get(full_module) or importlib.import_module(full_module)
+
+        if module_name.endswith('.py'):
+            if self.project_dir is None or not (self.project_dir / module_name).exists():
+                raise UsageError(f"Cannot find module '{module_name}' in project directory.")
+
+            if module_name in self._private_plugins:
+                return self._private_plugins[module_name]
+
+            file_path = str(self.project_dir / module_name)
+            spec = importlib.util.spec_from_file_location(module_name, file_path)
+            if spec:
+                module = importlib.util.module_from_spec(spec)
+                # Do not add to global modules because there is no standard
+                # module name that Python can resolve.
+                self._private_plugins[module_name] = module
+                assert spec.loader is not None
+                spec.loader.exec_module(module)
+
+                return module
+
+        return sys.modules.get(module_name) or importlib.import_module(module_name)
+
+
+    def find_config_file(self, filename: StrPath,
+                         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 directory.
+        """
+        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'))