117 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			117 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			Python
		
	
	
# Copyright 2017 New Vector Ltd
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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#     http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import importlib
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import importlib.util
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import itertools
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from types import ModuleType
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from typing import Any, Iterable, Tuple, Type
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import jsonschema
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from synapse.config._base import ConfigError
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from synapse.config._util import json_error_to_config_error
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def load_module(provider: dict, config_path: Iterable[str]) -> Tuple[Type, Any]:
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    """Loads a synapse module with its config
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    Args:
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        provider: a dict with keys 'module' (the module name) and 'config'
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           (the config dict).
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        config_path: the path within the config file. This will be used as a basis
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           for any error message.
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    Returns
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        Tuple of (provider class, parsed config object)
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    """
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    modulename = provider.get("module")
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    if not isinstance(modulename, str):
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        raise ConfigError(
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            "expected a string", path=itertools.chain(config_path, ("module",))
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        )
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    # We need to import the module, and then pick the class out of
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    # that, so we split based on the last dot.
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    module_name, clz = modulename.rsplit(".", 1)
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    module = importlib.import_module(module_name)
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    provider_class = getattr(module, clz)
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    # Load the module config. If None, pass an empty dictionary instead
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    module_config = provider.get("config") or {}
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    if hasattr(provider_class, "parse_config"):
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        try:
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            provider_config = provider_class.parse_config(module_config)
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        except jsonschema.ValidationError as e:
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            raise json_error_to_config_error(
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                e, itertools.chain(config_path, ("config",))
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            )
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        except ConfigError as e:
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            raise _wrap_config_error(
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                "Failed to parse config for module %r" % (modulename,),
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                prefix=itertools.chain(config_path, ("config",)),
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                e=e,
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            )
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        except Exception as e:
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            raise ConfigError(
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                "Failed to parse config for module %r" % (modulename,),
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                path=itertools.chain(config_path, ("config",)),
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            ) from e
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    else:
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        provider_config = module_config
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    return provider_class, provider_config
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def load_python_module(location: str) -> ModuleType:
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    """Load a python module, and return a reference to its global namespace
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    Args:
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        location: path to the module
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    Returns:
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        python module object
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    """
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    spec = importlib.util.spec_from_file_location(location, location)
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    if spec is None:
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        raise Exception("Unable to load module at %s" % (location,))
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    mod = importlib.util.module_from_spec(spec)
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    spec.loader.exec_module(mod)  # type: ignore
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    return mod
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def _wrap_config_error(
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    msg: str, prefix: Iterable[str], e: ConfigError
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) -> "ConfigError":
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    """Wrap a relative ConfigError with a new path
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    This is useful when we have a ConfigError with a relative path due to a problem
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    parsing part of the config, and we now need to set it in context.
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    """
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    path = prefix
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    if e.path:
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        path = itertools.chain(prefix, e.path)
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    e1 = ConfigError(msg, path)
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    # ideally we would set the 'cause' of the new exception to the original exception;
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    # however now that we have merged the path into our own, the stringification of
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    # e will be incorrect, so instead we create a new exception with just the "msg"
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    # part.
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    e1.__cause__ = Exception(e.msg)
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    e1.__cause__.__cause__ = e.__cause__
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    return e1
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