anonymousland-synapse/synapse/config/_util.py
Richard van der Hoff ab7a24cc6b
Better formatting for config errors from modules (#8874)
The idea is that the parse_config method of extension modules can raise either a ConfigError or a JsonValidationError,
and it will be magically turned into a legible error message. There's a few components to it:

* Separating the "path" and the "message" parts of a ConfigError, so that we can fiddle with the path bit to turn it
   into an absolute path.
* Generally improving the way ConfigErrors get printed.
* Passing in the config path to load_module so that it can wrap any exceptions that get caught appropriately.
2020-12-08 14:04:35 +00:00

65 lines
2.1 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2020 The Matrix.org Foundation C.I.C.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from typing import Any, Iterable
import jsonschema
from synapse.config._base import ConfigError
from synapse.types import JsonDict
def validate_config(
json_schema: JsonDict, config: Any, config_path: Iterable[str]
) -> None:
"""Validates a config setting against a JsonSchema definition
This can be used to validate a section of the config file against a schema
definition. If the validation fails, a ConfigError is raised with a textual
description of the problem.
Args:
json_schema: the schema to validate against
config: the configuration value to be validated
config_path: the path within the config file. This will be used as a basis
for the error message.
"""
try:
jsonschema.validate(config, json_schema)
except jsonschema.ValidationError as e:
raise json_error_to_config_error(e, config_path)
def json_error_to_config_error(
e: jsonschema.ValidationError, config_path: Iterable[str]
) -> ConfigError:
"""Converts a json validation error to a user-readable ConfigError
Args:
e: the exception to be converted
config_path: the path within the config file. This will be used as a basis
for the error message.
Returns:
a ConfigError
"""
# copy `config_path` before modifying it.
path = list(config_path)
for p in list(e.path):
if isinstance(p, int):
path.append("<item %i>" % p)
else:
path.append(str(p))
return ConfigError(e.message, path)