Rename Message.message_type to Message.type to match AMQP

The AMQP property is `type`, and pika uses `properties.type`.
Rename the Pydantic field to match, eliminating the awkward
`message_type` indirection. Consumer.message_type property is
unchanged for backward compatibility.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: gmr

docs/migrating.md

@@ -208,7 +208,8 @@ Key differences:
 
 - Properties are top-level fields on `Message`, not nested under
   `msg.properties`
-- The AMQP `type` property is accessed as `msg.message_type` (not `msg.type`)
+- The AMQP `type` property is accessed as `msg.type` (matching the AMQP
+  property name)
 - `Message` is a Pydantic `BaseModel` with validation
 - `body` starts as raw bytes; the `Codec` class decodes it asynchronously
   before the consumer sees it

rejected/consumer.py

@@ -155,19 +155,19 @@ def _pre_execute(
             msg.correlation_id or msg.message_id or str(uuid.uuid4())
         )
 
-        if msg.message_type:
-            self.set_sentry_context('type', msg.message_type)
+        if msg.type:
+            self.set_sentry_context('type', msg.type)
 
         # Validate message type
         if self.MESSAGE_TYPE:
             expected = self.MESSAGE_TYPE
             if isinstance(expected, (tuple, list, set)):
-                supported = msg.message_type in expected
+                supported = msg.type in expected
             else:
-                supported = msg.message_type == expected
+                supported = msg.type == expected
             if not supported:
                 self.logger.warning(
-                    'Received unsupported message type: %s', msg.message_type
+                    'Received unsupported message type: %s', msg.type
                 )
                 if self._drop_invalid:
                     if self._drop_exchange:
@@ -619,7 +619,7 @@ def message_id(self) -> str | None:
     def message_type(self) -> str | None:
         if not self._context:
             return None
-        return self._context.message.message_type
+        return self._context.message.type
 
     @property
     def priority(self) -> int | None:

rejected/models.py

@@ -142,7 +142,7 @@ class Message(pydantic.BaseModel):
         str, bool | dict[str, typing.Any] | float | int | str | bytes
     ]
     message_id: str | None
-    message_type: str | None
+    type: str | None
     priority: int | None
     redelivered: bool
     reply_to: str | None

rejected/process.py

@@ -291,10 +291,7 @@ async def invoke_consumer(self, ctx: models.ProcessingContext) -> None:
             msg = ctx.message
             try:
                 msg.body = await self.codec.decode(
-                    msg.body,
-                    msg.content_type,
-                    msg.content_encoding,
-                    msg.message_type,
+                    msg.body, msg.content_type, msg.content_encoding, msg.type
                 )
             except codecs.DecodeError as error:
                 LOGGER.error('Failed to decode message body: %s', error)
@@ -451,7 +448,7 @@ def on_message(
                     dict(properties.headers) if properties.headers else {}
                 ),
                 message_id=properties.message_id,
-                message_type=properties.type,
+                type=properties.type,
                 priority=properties.priority,
                 redelivered=redelivered,
                 reply_to=properties.reply_to,

rejected/testing.py

@@ -162,7 +162,7 @@ def create_context(
             expiration=properties.get('expiration'),
             headers=properties.get('headers', {}),
             message_id=properties.get('message_id', str(uuid.uuid4())),
-            message_type=properties.get('type'),
+            type=properties.get('type'),
             priority=properties.get('priority'),
             redelivered=False,
             reply_to=properties.get('reply_to'),

tests/test_consumer.py

@@ -24,7 +24,7 @@ def _make_message(**kwargs: typing.Any) -> models.Message:
         'expiration': '32768',
         'headers': {'foo': 'bar'},
         'message_id': 'mid123',
-        'message_type': 'test',
+        'type': 'test',
         'priority': 5,
         'redelivered': False,
         'reply_to': 'rtrk',
@@ -123,7 +123,7 @@ async def process(self):
                 pass
 
         obj = TypedConsumer(config_module.Settings({}), None)
-        ctx = _make_ctx(_make_message(message_type='wrong'))
+        ctx = _make_ctx(_make_message(type='wrong'))
         await obj.execute(ctx)
         self.assertEqual(ctx.result, models.Result.MESSAGE_DROP)
 
@@ -135,7 +135,7 @@ async def process(self):
                 pass
 
         obj = TypedConsumer(config_module.Settings({}), None)
-        ctx = _make_ctx(_make_message(message_type='wrong'))
+        ctx = _make_ctx(_make_message(type='wrong'))
         await obj.execute(ctx)
         self.assertEqual(ctx.result, models.Result.MESSAGE_EXCEPTION)
 
@@ -206,7 +206,7 @@ async def process(self):
         self.assertEqual(captured['expiration'], msg.expiration)
         self.assertEqual(captured['headers'], msg.headers)
         self.assertEqual(captured['message_id'], msg.message_id)
-        self.assertEqual(captured['message_type'], msg.message_type)
+        self.assertEqual(captured['message_type'], msg.type)
         self.assertEqual(captured['name'], 'PropConsumer')
         self.assertEqual(captured['priority'], msg.priority)
         self.assertEqual(captured['redelivered'], msg.redelivered)

tests/test_process.py

@@ -90,7 +90,7 @@ def _make_message(
         expiration='32768',
         headers={'foo': 'bar'},
         message_id='mid123',
-        message_type='test',
+        type='test',
         priority=5,
         redelivered=redelivered,
         reply_to='rtrk',