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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| 
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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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| 
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| import jsonschema
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| 
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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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| 
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| 
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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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| 
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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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| 
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|     Returns
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|         Tuple of (provider class, parsed config object)
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|     """
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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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| 
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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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| 
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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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| 
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|     return provider_class, provider_config
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| 
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| 
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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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| 
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|     Args:
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|         location: path to the module
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| 
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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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| 
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| 
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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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| 
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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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| 
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|     e1 = ConfigError(msg, path)
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| 
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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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| 
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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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