From fa7dc889f19f581e81624245ce7820525066eff3 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Wed, 1 Aug 2018 13:47:07 +0100 Subject: [PATCH 1/4] Be more careful which errors we send back over the C-S API We really shouldn't be sending all CodeMessageExceptions back over the C-S API; it will include things like 401s which we shouldn't proxy. That means that we need to explicitly turn a few HttpResponseExceptions into SynapseErrors in the federation layer. The effect of the latter is that the matrix errcode will get passed through correctly to calling clients, which might help with some of the random M_UNKNOWN errors when trying to join rooms. --- synapse/api/errors.py | 11 ---------- synapse/federation/federation_client.py | 29 +++++++++++++++---------- synapse/http/server.py | 14 +++++------- 3 files changed, 22 insertions(+), 32 deletions(-) diff --git a/synapse/api/errors.py b/synapse/api/errors.py index 6074df292..cf48829c8 100644 --- a/synapse/api/errors.py +++ b/synapse/api/errors.py @@ -69,9 +69,6 @@ class CodeMessageException(RuntimeError): self.code = code self.msg = msg - def error_dict(self): - return cs_error(self.msg) - class MatrixCodeMessageException(CodeMessageException): """An error from a general matrix endpoint, eg. from a proxied Matrix API call. @@ -308,14 +305,6 @@ class LimitExceededError(SynapseError): ) -def cs_exception(exception): - if isinstance(exception, CodeMessageException): - return exception.error_dict() - else: - logger.error("Unknown exception type: %s", type(exception)) - return {} - - def cs_error(msg, code=Codes.UNKNOWN, **kwargs): """ Utility method for constructing an error response for client-server interactions. diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py index baa9c3586..0b09f93ca 100644 --- a/synapse/federation/federation_client.py +++ b/synapse/federation/federation_client.py @@ -488,7 +488,7 @@ class FederationClient(FederationBase): The [Deferred] result of callback, if it succeeds Raises: - CodeMessageException if the chosen remote server returns a 300/400 code. + SynapseError if the chosen remote server returns a 300/400 code. RuntimeError if no servers were reachable. """ @@ -504,9 +504,9 @@ class FederationClient(FederationBase): "Failed to %s via %s: %s", description, destination, e, ) - except CodeMessageException as e: + except HttpResponseException as e: if not 500 <= e.code < 600: - raise + raise SynapseError.from_http_response_exception(e) else: logger.warn( "Failed to %s via %s: %i %s", @@ -543,7 +543,7 @@ class FederationClient(FederationBase): Deferred: resolves to a tuple of (origin (str), event (object)) where origin is the remote homeserver which generated the event. - Fails with a ``CodeMessageException`` if the chosen remote server + Fails with a ``SynapseError`` if the chosen remote server returns a 300/400 code. Fails with a ``RuntimeError`` if no servers were reachable. @@ -599,7 +599,7 @@ class FederationClient(FederationBase): giving the serer the event was sent to, ``state`` (?) and ``auth_chain``. - Fails with a ``CodeMessageException`` if the chosen remote server + Fails with a ``SynapseError`` if the chosen remote server returns a 300/400 code. Fails with a ``RuntimeError`` if no servers were reachable. @@ -673,12 +673,17 @@ class FederationClient(FederationBase): @defer.inlineCallbacks def send_invite(self, destination, room_id, event_id, pdu): time_now = self._clock.time_msec() - code, content = yield self.transport_layer.send_invite( - destination=destination, - room_id=room_id, - event_id=event_id, - content=pdu.get_pdu_json(time_now), - ) + try: + code, content = yield self.transport_layer.send_invite( + destination=destination, + room_id=room_id, + event_id=event_id, + content=pdu.get_pdu_json(time_now), + ) + except HttpResponseException as e: + if e.code == 403: + raise SynapseError.from_http_response_exception(e) + raise pdu_dict = content["event"] @@ -709,7 +714,7 @@ class FederationClient(FederationBase): Return: Deferred: resolves to None. - Fails with a ``CodeMessageException`` if the chosen remote server + Fails with a ``SynapseError`` if the chosen remote server returns a 300/400 code. Fails with a ``RuntimeError`` if no servers were reachable. diff --git a/synapse/http/server.py b/synapse/http/server.py index 1940c1c4f..6dacb3103 100644 --- a/synapse/http/server.py +++ b/synapse/http/server.py @@ -36,7 +36,6 @@ from synapse.api.errors import ( Codes, SynapseError, UnrecognizedRequestError, - cs_exception, ) from synapse.http.request_metrics import requests_counter from synapse.util.caches import intern_dict @@ -77,16 +76,13 @@ def wrap_json_request_handler(h): def wrapped_request_handler(self, request): try: yield h(self, request) - except CodeMessageException as e: + except SynapseError as e: code = e.code - if isinstance(e, SynapseError): - logger.info( - "%s SynapseError: %s - %s", request, code, e.msg - ) - else: - logger.exception(e) + logger.info( + "%s SynapseError: %s - %s", request, code, e.msg + ) respond_with_json( - request, code, cs_exception(e), send_cors=True, + request, code, e.error_dict(), send_cors=True, pretty_print=_request_user_agent_is_curl(request), ) From 018d75a148ced6945aca7b095a272e0edba5aae1 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Wed, 1 Aug 2018 14:58:16 +0100 Subject: [PATCH 2/4] Refactor code for turning HttpResponseException into SynapseError This commit replaces SynapseError.from_http_response_exception with HttpResponseException.to_synapse_error. The new method actually returns a ProxiedRequestError, which allows us to pass through additional metadata from the API call. --- synapse/api/errors.py | 84 ++++++++++++++--------- synapse/federation/federation_client.py | 4 +- synapse/rest/media/v1/media_repository.py | 2 +- 3 files changed, 56 insertions(+), 34 deletions(-) diff --git a/synapse/api/errors.py b/synapse/api/errors.py index cf48829c8..7476c90ed 100644 --- a/synapse/api/errors.py +++ b/synapse/api/errors.py @@ -105,38 +105,28 @@ class SynapseError(CodeMessageException): self.errcode, ) - @classmethod - def from_http_response_exception(cls, err): - """Make a SynapseError based on an HTTPResponseException - This is useful when a proxied request has failed, and we need to - decide how to map the failure onto a matrix error to send back to the - client. +class ProxiedRequestError(SynapseError): + """An error from a general matrix endpoint, eg. from a proxied Matrix API call. - An attempt is made to parse the body of the http response as a matrix - error. If that succeeds, the errcode and error message from the body - are used as the errcode and error message in the new synapse error. + Attributes: + errcode (str): Matrix error code e.g 'M_FORBIDDEN' + """ + def __init__(self, code, msg, errcode=Codes.UNKNOWN, additional_fields=None): + super(ProxiedRequestError, self).__init__( + code, msg, errcode + ) + if additional_fields is None: + self._additional_fields = {} + else: + self._additional_fields = dict(additional_fields) - Otherwise, the errcode is set to M_UNKNOWN, and the error message is - set to the reason code from the HTTP response. - - Args: - err (HttpResponseException): - - Returns: - SynapseError: - """ - # try to parse the body as json, to get better errcode/msg, but - # default to M_UNKNOWN with the HTTP status as the error text - try: - j = json.loads(err.response) - except ValueError: - j = {} - errcode = j.get('errcode', Codes.UNKNOWN) - errmsg = j.get('error', err.msg) - - res = SynapseError(err.code, errmsg, errcode) - return res + def error_dict(self): + return cs_error( + self.msg, + self.errcode, + **self._additional_fields + ) class ConsentNotGivenError(SynapseError): @@ -361,7 +351,7 @@ class HttpResponseException(CodeMessageException): Represents an HTTP-level failure of an outbound request Attributes: - response (str): body of response + response (bytes): body of response """ def __init__(self, code, msg, response): """ @@ -369,7 +359,39 @@ class HttpResponseException(CodeMessageException): Args: code (int): HTTP status code msg (str): reason phrase from HTTP response status line - response (str): body of response + response (bytes): body of response """ super(HttpResponseException, self).__init__(code, msg) self.response = response + + def to_synapse_error(self): + """Make a SynapseError based on an HTTPResponseException + + This is useful when a proxied request has failed, and we need to + decide how to map the failure onto a matrix error to send back to the + client. + + An attempt is made to parse the body of the http response as a matrix + error. If that succeeds, the errcode and error message from the body + are used as the errcode and error message in the new synapse error. + + Otherwise, the errcode is set to M_UNKNOWN, and the error message is + set to the reason code from the HTTP response. + + Returns: + SynapseError: + """ + # try to parse the body as json, to get better errcode/msg, but + # default to M_UNKNOWN with the HTTP status as the error text + try: + j = json.loads(self.response) + except ValueError: + j = {} + + if not isinstance(j, dict): + j = {} + + errcode = j.pop('errcode', Codes.UNKNOWN) + errmsg = j.pop('error', self.msg) + + return ProxiedRequestError(self.code, errmsg, errcode, j) diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py index 0b09f93ca..7550e11b6 100644 --- a/synapse/federation/federation_client.py +++ b/synapse/federation/federation_client.py @@ -506,7 +506,7 @@ class FederationClient(FederationBase): ) except HttpResponseException as e: if not 500 <= e.code < 600: - raise SynapseError.from_http_response_exception(e) + raise e.to_synapse_error() else: logger.warn( "Failed to %s via %s: %i %s", @@ -682,7 +682,7 @@ class FederationClient(FederationBase): ) except HttpResponseException as e: if e.code == 403: - raise SynapseError.from_http_response_exception(e) + raise e.to_synapse_error() raise pdu_dict = content["event"] diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py index 174ad2012..8fb413d82 100644 --- a/synapse/rest/media/v1/media_repository.py +++ b/synapse/rest/media/v1/media_repository.py @@ -379,7 +379,7 @@ class MediaRepository(object): logger.warn("HTTP error fetching remote media %s/%s: %s", server_name, media_id, e.response) if e.code == twisted.web.http.NOT_FOUND: - raise SynapseError.from_http_response_exception(e) + raise e.to_synapse_error() raise SynapseError(502, "Failed to fetch remote media") except SynapseError: From 01e93f48ed3dd78fda45a37733251659af19dde3 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Wed, 1 Aug 2018 15:04:50 +0100 Subject: [PATCH 3/4] Kill off MatrixCodeMessageException This code brings the SimpleHttpClient into line with the MatrixFederationHttpClient by having it raise HttpResponseExceptions when a request fails (rather than trying to parse for matrix errors and maybe raising MatrixCodeMessageException). Then, whenever we were checking for MatrixCodeMessageException and turning them into SynapseErrors, we now need to check for HttpResponseExceptions and call to_synapse_error. --- synapse/api/errors.py | 11 ----- synapse/handlers/identity.py | 25 ++++------- synapse/http/client.py | 61 ++++++++++++-------------- synapse/replication/http/membership.py | 18 ++++---- synapse/replication/http/send_event.py | 10 ++--- 5 files changed, 47 insertions(+), 78 deletions(-) diff --git a/synapse/api/errors.py b/synapse/api/errors.py index 7476c90ed..356836238 100644 --- a/synapse/api/errors.py +++ b/synapse/api/errors.py @@ -70,17 +70,6 @@ class CodeMessageException(RuntimeError): self.msg = msg -class MatrixCodeMessageException(CodeMessageException): - """An error from a general matrix endpoint, eg. from a proxied Matrix API call. - - Attributes: - errcode (str): Matrix error code e.g 'M_FORBIDDEN' - """ - def __init__(self, code, msg, errcode=Codes.UNKNOWN): - super(MatrixCodeMessageException, self).__init__(code, msg) - self.errcode = errcode - - class SynapseError(CodeMessageException): """A base exception type for matrix errors which have an errcode and error message (as well as an HTTP status code). diff --git a/synapse/handlers/identity.py b/synapse/handlers/identity.py index 8c8aedb2b..1d36d967c 100644 --- a/synapse/handlers/identity.py +++ b/synapse/handlers/identity.py @@ -26,7 +26,7 @@ from twisted.internet import defer from synapse.api.errors import ( CodeMessageException, Codes, - MatrixCodeMessageException, + HttpResponseException, SynapseError, ) @@ -85,7 +85,6 @@ class IdentityHandler(BaseHandler): ) defer.returnValue(None) - data = {} try: data = yield self.http_client.get_json( "https://%s%s" % ( @@ -94,11 +93,9 @@ class IdentityHandler(BaseHandler): ), {'sid': creds['sid'], 'client_secret': client_secret} ) - except MatrixCodeMessageException as e: + except HttpResponseException as e: logger.info("getValidated3pid failed with Matrix error: %r", e) - raise SynapseError(e.code, e.msg, e.errcode) - except CodeMessageException as e: - data = json.loads(e.msg) + raise e.to_synapse_error() if 'medium' in data: defer.returnValue(data) @@ -136,7 +133,7 @@ class IdentityHandler(BaseHandler): ) logger.debug("bound threepid %r to %s", creds, mxid) except CodeMessageException as e: - data = json.loads(e.msg) + data = json.loads(e.msg) # XXX WAT? defer.returnValue(data) @defer.inlineCallbacks @@ -209,12 +206,9 @@ class IdentityHandler(BaseHandler): params ) defer.returnValue(data) - except MatrixCodeMessageException as e: - logger.info("Proxied requestToken failed with Matrix error: %r", e) - raise SynapseError(e.code, e.msg, e.errcode) - except CodeMessageException as e: + except HttpResponseException as e: logger.info("Proxied requestToken failed: %r", e) - raise e + raise e.to_synapse_error() @defer.inlineCallbacks def requestMsisdnToken( @@ -244,9 +238,6 @@ class IdentityHandler(BaseHandler): params ) defer.returnValue(data) - except MatrixCodeMessageException as e: - logger.info("Proxied requestToken failed with Matrix error: %r", e) - raise SynapseError(e.code, e.msg, e.errcode) - except CodeMessageException as e: + except HttpResponseException as e: logger.info("Proxied requestToken failed: %r", e) - raise e + raise e.to_synapse_error() diff --git a/synapse/http/client.py b/synapse/http/client.py index 25b630788..3771e0b3f 100644 --- a/synapse/http/client.py +++ b/synapse/http/client.py @@ -39,12 +39,7 @@ from twisted.web.client import ( from twisted.web.http import PotentialDataLoss from twisted.web.http_headers import Headers -from synapse.api.errors import ( - CodeMessageException, - Codes, - MatrixCodeMessageException, - SynapseError, -) +from synapse.api.errors import Codes, HttpResponseException, SynapseError from synapse.http import cancelled_to_request_timed_out_error, redact_uri from synapse.http.endpoint import SpiderEndpoint from synapse.util.async import add_timeout_to_deferred @@ -132,6 +127,11 @@ class SimpleHttpClient(object): Returns: Deferred[object]: parsed json + + Raises: + HttpResponseException: On a non-2xx HTTP response. + + ValueError: if the response was not JSON """ # TODO: Do we ever want to log message contents? @@ -155,7 +155,10 @@ class SimpleHttpClient(object): body = yield make_deferred_yieldable(readBody(response)) - defer.returnValue(json.loads(body)) + if 200 <= response.code < 300: + defer.returnValue(json.loads(body)) + else: + raise HttpResponseException(response.code, response.phrase, body) @defer.inlineCallbacks def post_json_get_json(self, uri, post_json, headers=None): @@ -169,6 +172,11 @@ class SimpleHttpClient(object): Returns: Deferred[object]: parsed json + + Raises: + HttpResponseException: On a non-2xx HTTP response. + + ValueError: if the response was not JSON """ json_str = encode_canonical_json(post_json) @@ -193,9 +201,7 @@ class SimpleHttpClient(object): if 200 <= response.code < 300: defer.returnValue(json.loads(body)) else: - raise self._exceptionFromFailedRequest(response, body) - - defer.returnValue(json.loads(body)) + raise HttpResponseException(response.code, response.phrase, body) @defer.inlineCallbacks def get_json(self, uri, args={}, headers=None): @@ -213,14 +219,12 @@ class SimpleHttpClient(object): Deferred: Succeeds when we get *any* 2xx HTTP response, with the HTTP body as JSON. Raises: - On a non-2xx HTTP response. The response body will be used as the - error message. + HttpResponseException On a non-2xx HTTP response. + + ValueError: if the response was not JSON """ - try: - body = yield self.get_raw(uri, args, headers=headers) - defer.returnValue(json.loads(body)) - except CodeMessageException as e: - raise self._exceptionFromFailedRequest(e.code, e.msg) + body = yield self.get_raw(uri, args, headers=headers) + defer.returnValue(json.loads(body)) @defer.inlineCallbacks def put_json(self, uri, json_body, args={}, headers=None): @@ -239,7 +243,9 @@ class SimpleHttpClient(object): Deferred: Succeeds when we get *any* 2xx HTTP response, with the HTTP body as JSON. Raises: - On a non-2xx HTTP response. + HttpResponseException On a non-2xx HTTP response. + + ValueError: if the response was not JSON """ if len(args): query_bytes = urllib.urlencode(args, True) @@ -266,10 +272,7 @@ class SimpleHttpClient(object): if 200 <= response.code < 300: defer.returnValue(json.loads(body)) else: - # NB: This is explicitly not json.loads(body)'d because the contract - # of CodeMessageException is a *string* message. Callers can always - # load it into JSON if they want. - raise CodeMessageException(response.code, body) + raise HttpResponseException(response.code, response.phrase, body) @defer.inlineCallbacks def get_raw(self, uri, args={}, headers=None): @@ -287,8 +290,7 @@ class SimpleHttpClient(object): Deferred: Succeeds when we get *any* 2xx HTTP response, with the HTTP body at text. Raises: - On a non-2xx HTTP response. The response body will be used as the - error message. + HttpResponseException on a non-2xx HTTP response. """ if len(args): query_bytes = urllib.urlencode(args, True) @@ -311,16 +313,7 @@ class SimpleHttpClient(object): if 200 <= response.code < 300: defer.returnValue(body) else: - raise CodeMessageException(response.code, body) - - def _exceptionFromFailedRequest(self, response, body): - try: - jsonBody = json.loads(body) - errcode = jsonBody['errcode'] - error = jsonBody['error'] - return MatrixCodeMessageException(response.code, error, errcode) - except (ValueError, KeyError): - return CodeMessageException(response.code, body) + raise HttpResponseException(response.code, response.phrase, body) # XXX: FIXME: This is horribly copy-pasted from matrixfederationclient. # The two should be factored out. diff --git a/synapse/replication/http/membership.py b/synapse/replication/http/membership.py index 6bfc8a5b8..7a3cfb159 100644 --- a/synapse/replication/http/membership.py +++ b/synapse/replication/http/membership.py @@ -18,7 +18,7 @@ import re from twisted.internet import defer -from synapse.api.errors import MatrixCodeMessageException, SynapseError +from synapse.api.errors import HttpResponseException from synapse.http.servlet import RestServlet, parse_json_object_from_request from synapse.types import Requester, UserID from synapse.util.distributor import user_joined_room, user_left_room @@ -56,11 +56,11 @@ def remote_join(client, host, port, requester, remote_room_hosts, try: result = yield client.post_json_get_json(uri, payload) - except MatrixCodeMessageException as e: + except HttpResponseException as e: # We convert to SynapseError as we know that it was a SynapseError # on the master process that we should send to the client. (And # importantly, not stack traces everywhere) - raise SynapseError(e.code, e.msg, e.errcode) + raise e.to_synapse_error() defer.returnValue(result) @@ -92,11 +92,11 @@ def remote_reject_invite(client, host, port, requester, remote_room_hosts, try: result = yield client.post_json_get_json(uri, payload) - except MatrixCodeMessageException as e: + except HttpResponseException as e: # We convert to SynapseError as we know that it was a SynapseError # on the master process that we should send to the client. (And # importantly, not stack traces everywhere) - raise SynapseError(e.code, e.msg, e.errcode) + raise e.to_synapse_error() defer.returnValue(result) @@ -131,11 +131,11 @@ def get_or_register_3pid_guest(client, host, port, requester, try: result = yield client.post_json_get_json(uri, payload) - except MatrixCodeMessageException as e: + except HttpResponseException as e: # We convert to SynapseError as we know that it was a SynapseError # on the master process that we should send to the client. (And # importantly, not stack traces everywhere) - raise SynapseError(e.code, e.msg, e.errcode) + raise e.to_synapse_error() defer.returnValue(result) @@ -165,11 +165,11 @@ def notify_user_membership_change(client, host, port, user_id, room_id, change): try: result = yield client.post_json_get_json(uri, payload) - except MatrixCodeMessageException as e: + except HttpResponseException as e: # We convert to SynapseError as we know that it was a SynapseError # on the master process that we should send to the client. (And # importantly, not stack traces everywhere) - raise SynapseError(e.code, e.msg, e.errcode) + raise e.to_synapse_error() defer.returnValue(result) diff --git a/synapse/replication/http/send_event.py b/synapse/replication/http/send_event.py index 5227bc333..d3509dc28 100644 --- a/synapse/replication/http/send_event.py +++ b/synapse/replication/http/send_event.py @@ -18,11 +18,7 @@ import re from twisted.internet import defer -from synapse.api.errors import ( - CodeMessageException, - MatrixCodeMessageException, - SynapseError, -) +from synapse.api.errors import CodeMessageException, HttpResponseException from synapse.events import FrozenEvent from synapse.events.snapshot import EventContext from synapse.http.servlet import RestServlet, parse_json_object_from_request @@ -83,11 +79,11 @@ def send_event_to_master(clock, store, client, host, port, requester, event, con # If we timed out we probably don't need to worry about backing # off too much, but lets just wait a little anyway. yield clock.sleep(1) - except MatrixCodeMessageException as e: + except HttpResponseException as e: # We convert to SynapseError as we know that it was a SynapseError # on the master process that we should send to the client. (And # importantly, not stack traces everywhere) - raise SynapseError(e.code, e.msg, e.errcode) + raise e.to_synapse_error() defer.returnValue(result) From 908be65e646ba933d595f3d8874cee69774e7243 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Wed, 1 Aug 2018 16:23:31 +0100 Subject: [PATCH 4/4] changelog --- changelog.d/3639.feature | 1 + 1 file changed, 1 insertion(+) create mode 100644 changelog.d/3639.feature diff --git a/changelog.d/3639.feature b/changelog.d/3639.feature new file mode 100644 index 000000000..c8c387e21 --- /dev/null +++ b/changelog.d/3639.feature @@ -0,0 +1 @@ +When we fail to join a room over federation, pass the error code back to the client. \ No newline at end of file