Reference Matrix Home Server

synapse/api/errors.py

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+# -*- coding: utf-8 -*-
+# Copyright 2014 matrix.org
+#
+# 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.
+"""Contains exceptions and error codes."""
+
+import logging
+
+
+class Codes(object):
+    FORBIDDEN = "M_FORBIDDEN"
+    BAD_JSON = "M_BAD_JSON"
+    NOT_JSON = "M_NOT_JSON"
+    USER_IN_USE = "M_USER_IN_USE"
+    ROOM_IN_USE = "M_ROOM_IN_USE"
+    BAD_PAGINATION = "M_BAD_PAGINATION"
+    UNKNOWN = "M_UNKNOWN"
+    NOT_FOUND = "M_NOT_FOUND"
+
+
+class CodeMessageException(Exception):
+    """An exception with integer code and message string attributes."""
+
+    def __init__(self, code, msg):
+        logging.error("%s: %s, %s", type(self).__name__, code, msg)
+        super(CodeMessageException, self).__init__("%d: %s" % (code, msg))
+        self.code = code
+        self.msg = msg
+
+
+class SynapseError(CodeMessageException):
+    """A base error which can be caught for all synapse events."""
+    def __init__(self, code, msg, errcode=""):
+        """Constructs a synapse error.
+
+        Args:
+            code (int): The integer error code (typically an HTTP response code)
+            msg (str): The human-readable error message.
+            err (str): The error code e.g 'M_FORBIDDEN'
+        """
+        super(SynapseError, self).__init__(code, msg)
+        self.errcode = errcode
+
+
+class RoomError(SynapseError):
+    """An error raised when a room event fails."""
+    pass
+
+
+class RegistrationError(SynapseError):
+    """An error raised when a registration event fails."""
+    pass
+
+
+class AuthError(SynapseError):
+    """An error raised when there was a problem authorising an event."""
+
+    def __init__(self, *args, **kwargs):
+        if "errcode" not in kwargs:
+            kwargs["errcode"] = Codes.FORBIDDEN
+        super(AuthError, self).__init__(*args, **kwargs)
+
+
+class EventStreamError(SynapseError):
+    """An error raised when there a problem with the event stream."""
+    pass
+
+
+class LoginError(SynapseError):
+    """An error raised when there was a problem logging in."""
+    pass
+
+
+class StoreError(SynapseError):
+    """An error raised when there was a problem storing some data."""
+    pass
+
+
+def cs_exception(exception):
+    if isinstance(exception, SynapseError):
+        return cs_error(
+            exception.msg,
+            Codes.UNKNOWN if not exception.errcode else exception.errcode)
+    elif isinstance(exception, CodeMessageException):
+        return cs_error(exception.msg)
+    else:
+        logging.error("Unknown exception type: %s", type(exception))
+
+
+def cs_error(msg, code=Codes.UNKNOWN, **kwargs):
+    """ Utility method for constructing an error response for client-server
+    interactions.
+
+    Args:
+        msg (str): The error message.
+        code (int): The error code.
+        kwargs : Additional keys to add to the response.
+    Returns:
+        A dict representing the error response JSON.
+    """
+    err = {"error": msg, "errcode": code}
+    for key, value in kwargs.iteritems():
+        err[key] = value
+    return err