Fix 1988

.audit/oberstet_fix_1988.md

@@ -0,0 +1,8 @@
+- [ ] I did **not** use any AI-assistance tools to help create this pull request.
+- [x] I **did** use AI-assistance tools to *help* create this pull request.
+- [x] I have read, understood and followed the project's AI_POLICY.md when creating code, documentation etc. for this pull request.
+
+Submitted by: @oberstet
+Date: 2026-10-18
+Related issue(s): #1988
+Branch: oberstet:fix_1988

docs/changelog.rst

@@ -25,6 +25,7 @@ Changelog
 **asyncio**
 
 * Fix ``autobahn.asyncio.component.run()``, ``ApplicationRunner.run()``, ``Component.start()`` and the asyncio WebSocket factories failing on CPython 3.14 with ``RuntimeError: There is no current event loop`` when started from plain synchronous code (and the ``DeprecationWarning`` on 3.12 / 3.13): CPython no longer creates the loop implicitly in ``asyncio.get_event_loop()``. A new helper ``autobahn.asyncio.util.get_or_create_event_loop()`` returns the running loop, else the loop set for the thread, else a new one; ``run()`` was first fixed by Lukas Komischke (#1952, #1953), the remaining call sites follow, with a regression test that runs each case in a fresh interpreter (#1965)
+* Fix ``ApplicationSession.call()`` on asyncio raising ``AttributeError`` instead of the payload codec's exception when the payload codec fails to encode the call: the error was logged with ``log.failure()``, which only the Twisted logger has. It is now logged with ``log.error()`` and the traceback, on both Twisted and asyncio, and the codec's exception reaches the caller (#1988)
 
 **Dependencies**
 

src/autobahn/wamp/protocol.py

@@ -1947,7 +1947,13 @@ def call(self, procedure: str, *args, **kwargs) -> Any | CallResult:
                     True, procedure, args, kwargs
                 )
             except:
-                self.log.failure()
+                # log.failure() exists on Twisted only, so log the traceback
+                # explicitly - this works on both Twisted and asyncio (#1988)
+                self.log.error(
+                    "payload codec failed to encode call to {procedure}:\n{tb}",
+                    procedure=procedure,
+                    tb=txaio.failure_format_traceback(txaio.create_failure()),
+                )
                 raise
 
         if encoded_payload:

src/autobahn/wamp/test/test_wamp_payload_codec_error.py

@@ -0,0 +1,101 @@
+###############################################################################
+#
+# The MIT License (MIT)
+#
+# Copyright (c) typedef int GmbH
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+###############################################################################
+
+# Issue #1988: ApplicationSession.call() with a payload codec whose encode()
+# raises must re-raise the codec's exception, on Twisted AND asyncio.
+# Backend-neutral: runs under trial (USE_TWISTED) and pytest (USE_ASYNCIO).
+# session.log is deliberately NOT mocked: a Mock has every method, so it
+# would hide a logger method that one backend lacks.
+
+import os
+import unittest
+
+from autobahn.wamp.types import TransportDetails
+
+USE_TWISTED = bool(os.environ.get("USE_TWISTED", False))
+
+if USE_TWISTED:
+    from autobahn.twisted.wamp import ApplicationSession
+else:
+    from autobahn.asyncio.wamp import ApplicationSession
+
+
+class CodecError(Exception):
+    pass
+
+
+class FailingPayloadCodec:
+    def encode(self, is_originating, uri, args=None, kwargs=None):
+        raise CodecError("encode failed")
+
+    def decode(self, is_originating, uri, encoded_payload):
+        raise NotImplementedError()
+
+
+class MockTransport:
+    def __init__(self):
+        self.messages = []
+        self._transport_details = TransportDetails()
+
+    def transport_details(self):
+        return self._transport_details
+
+    def send(self, msg):
+        self.messages.append(msg)
+
+    def close(self, *args, **kw):
+        pass
+
+
+def check_call_reraises_payload_codec_error(test: unittest.TestCase) -> None:
+    session = ApplicationSession()
+    session._transport = MockTransport()
+    session._payload_codec = FailingPayloadCodec()
+
+    with test.assertRaises(CodecError):
+        session.call("com.example.procedure", 1, 2)
+
+    # nothing went out on the wire
+    test.assertEqual(session._transport.messages, [])
+
+
+# One class per backend (a base class chosen at import time is a union type,
+# which the type checker cannot use as a base).
+if USE_TWISTED:
+    from twisted.trial import unittest as trial_unittest
+
+    class TestPayloadCodecError(trial_unittest.TestCase):
+        def test_call_reraises_payload_codec_error(self):
+            check_call_reraises_payload_codec_error(self)
+            # trial fails a test that logged a Failure; the error is logged
+            # on purpose (if it is logged as a Failure at all), so accept it
+            self.flushLoggedErrors(CodecError)
+
+else:
+
+    class TestPayloadCodecError(unittest.TestCase):
+        def test_call_reraises_payload_codec_error(self):
+            check_call_reraises_payload_codec_error(self)