Add stricter checking when decoding with .from_payload()

Earlier, it was possible that a protobuf payload not including a certain
message was decoded using .from_payload(). For example when using
GetConfigsRequest.from_payload() with a message missing
GenericMessage::wirepas::get_configs_req, the library was not reporting
an error and setting the req_id to 0 even though it was not initialized
in the protobuf message.

If that happens now, and InvalidMessageType exception is raised. This
exception has the GatewayAPIParsingException as its parent to help with
backwards compatibility.

Also refactoring the tests and having a new test file for decoding
related error testing.

tests/default_value.py

@@ -24,8 +24,6 @@
 
 IMPLEMENTED_API_VERSION = 0
 
-INVALID_PROTOBUF_MESSAGE = bytes([0])
-
 # Todo add more fields in config
 NODE_CONFIG_1 = dict([("sink_id", SINK_ID), ("node_address", 123)])
 

tests/test_decoding_errors.py

@@ -0,0 +1,64 @@
+# flake8: noqa
+
+import pytest
+
+import wirepas_mesh_messaging
+from wirepas_mesh_messaging.proto import GenericMessage
+from wirepas_mesh_messaging.wirepas_exceptions import (
+    GatewayAPIParsingException,
+    InvalidMessageType,
+)
+
+MESSAGE_CLASSES = [
+    wirepas_mesh_messaging.GetConfigsRequest,
+    wirepas_mesh_messaging.GetConfigsResponse,
+    wirepas_mesh_messaging.GetGatewayInfoRequest,
+    wirepas_mesh_messaging.GetGatewayInfoResponse,
+    wirepas_mesh_messaging.GetScratchpadStatusRequest,
+    wirepas_mesh_messaging.GetScratchpadStatusResponse,
+    wirepas_mesh_messaging.ProcessScratchpadRequest,
+    wirepas_mesh_messaging.ProcessScratchpadResponse,
+    wirepas_mesh_messaging.ReceivedDataEvent,
+    wirepas_mesh_messaging.SendDataRequest,
+    wirepas_mesh_messaging.SendDataResponse,
+    wirepas_mesh_messaging.SetConfigRequest,
+    wirepas_mesh_messaging.SetConfigResponse,
+    wirepas_mesh_messaging.SetScratchpadTargetAndActionRequest,
+    wirepas_mesh_messaging.SetScratchpadTargetAndActionResponse,
+    wirepas_mesh_messaging.StatusEvent,
+    wirepas_mesh_messaging.UploadScratchpadRequest,
+    wirepas_mesh_messaging.UploadScratchpadResponse,
+]
+
+
+def _get_payload_excluding_message_type(message_class):
+    if message_class == wirepas_mesh_messaging.GetConfigsRequest:
+        return wirepas_mesh_messaging.GetGatewayInfoRequest().payload
+
+    return wirepas_mesh_messaging.GetConfigsRequest().payload
+
+
+@pytest.mark.parametrize("message_class", MESSAGE_CLASSES)
+def test_decoding_errors(message_class):
+    invalid_protobuf_message = bytes([0])
+
+    with pytest.raises(GatewayAPIParsingException, match="Cannot decode"):
+        message_class.from_payload(invalid_protobuf_message)
+
+
+@pytest.mark.parametrize("message_class", MESSAGE_CLASSES)
+def test_decoding_wrong_message_type(message_class):
+    payload = _get_payload_excluding_message_type(message_class)
+
+    with pytest.raises(InvalidMessageType, match=message_class.__name__):
+        message_class.from_payload(payload)
+
+
+@pytest.mark.parametrize("message_class", MESSAGE_CLASSES)
+def test_decoding_missing_message_type(message_class):
+    message = GenericMessage()
+    message.wirepas.SetInParent()
+    payload = message.SerializeToString()
+
+    with pytest.raises(InvalidMessageType, match=message_class.__name__):
+        message_class.from_payload(payload)

tests/test_get_configs.py

@@ -1,9 +1,7 @@
 # flake8: noqa
 
-import pytest
 import wirepas_mesh_messaging
 from default_value import *
-from wirepas_mesh_messaging.wirepas_exceptions import GatewayAPIParsingException
 
 DUMMY_CONFIGS = [NODE_CONFIG_2]
 
@@ -30,11 +28,3 @@ def test_generate_parse_response():
 
     for k, v in request.__dict__.items():
         assert v == request2.__dict__[k]
-
-def test_request_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.GetConfigsRequest.from_payload(INVALID_PROTOBUF_MESSAGE)
-
-def test_response_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.GetConfigsResponse.from_payload(INVALID_PROTOBUF_MESSAGE)

tests/test_get_gw_info.py

@@ -1,12 +1,9 @@
 # flake8: noqa
 
-import pytest
 import wirepas_mesh_messaging
 from default_value import *
 import time
 
-from wirepas_mesh_messaging.wirepas_exceptions import GatewayAPIParsingException
-
 
 def test_generate_parse_request():
     request = wirepas_mesh_messaging.GetGatewayInfoRequest(REQUEST_ID)
@@ -57,11 +54,3 @@ def test_generate_parse_response_not_all_optional():
     for k, v in request.__dict__.items():
         print(k)
         assert v == request2.__dict__[k]
-
-def test_request_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.GetGatewayInfoRequest.from_payload(INVALID_PROTOBUF_MESSAGE)
-
-def test_response_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.GetGatewayInfoResponse.from_payload(INVALID_PROTOBUF_MESSAGE)

tests/test_get_scratchpad_status.py

@@ -1,10 +1,8 @@
 # flake8: noqa
 
-import pytest
 import wirepas_mesh_messaging
 import enum
 from default_value import *
-from wirepas_mesh_messaging.wirepas_exceptions import GatewayAPIParsingException
 
 
 def test_generate_parse_request():
@@ -44,11 +42,3 @@ def test_generate_parse_response():
             assert v.value == request2.__dict__[k].value
         else:
             assert v == request2.__dict__[k]
-
-def test_request_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.GetScratchpadStatusRequest.from_payload(INVALID_PROTOBUF_MESSAGE)
-
-def test_response_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.GetScratchpadStatusResponse.from_payload(INVALID_PROTOBUF_MESSAGE)

tests/test_process_scratchpad.py

@@ -1,9 +1,7 @@
 # flake8: noqa
 
-import pytest
 import wirepas_mesh_messaging
 from default_value import *
-from wirepas_mesh_messaging.wirepas_exceptions import GatewayAPIParsingException
 
 
 def test_generate_parse_request():
@@ -31,11 +29,3 @@ def test_generate_parse_response():
 
     for k, v in request.__dict__.items():
         assert v == request2.__dict__[k]
-
-def test_request_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.ProcessScratchpadRequest.from_payload(INVALID_PROTOBUF_MESSAGE)
-
-def test_response_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.ProcessScratchpadResponse.from_payload(INVALID_PROTOBUF_MESSAGE)

tests/test_received_data.py

@@ -1,9 +1,7 @@
 # flake8: noqa
 
-import pytest
 import wirepas_mesh_messaging
 from default_value import *
-from wirepas_mesh_messaging.wirepas_exceptions import GatewayAPIParsingException
 
 
 def test_generate_parse_event():
@@ -75,7 +73,3 @@ def test_generate_parse_event_with_network_address():
 
     for k, v in status.__dict__.items():
         assert v == status2.__dict__[k]
-
-def test_event_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.ReceivedDataEvent.from_payload(INVALID_PROTOBUF_MESSAGE)

tests/test_send_data.py

@@ -1,9 +1,7 @@
 # flake8: noqa
 
-import pytest
 import wirepas_mesh_messaging
 from default_value import *
-from wirepas_mesh_messaging.wirepas_exceptions import GatewayAPIParsingException
 
 
 def test_generate_parse_request():
@@ -39,11 +37,3 @@ def test_generate_parse_response():
 
     for k, v in response.__dict__.items():
         assert v == response2.__dict__[k]
-
-def test_request_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.SendDataRequest.from_payload(INVALID_PROTOBUF_MESSAGE)
-
-def test_response_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.SendDataResponse.from_payload(INVALID_PROTOBUF_MESSAGE)

tests/test_set_config.py

@@ -1,9 +1,7 @@
 # flake8: noqa
 
-import pytest
 import wirepas_mesh_messaging
 from default_value import *
-from wirepas_mesh_messaging.wirepas_exceptions import GatewayAPIParsingException
 
 
 def test_generate_parse_request():
@@ -30,11 +28,3 @@ def test_generate_parse_response():
 
     for k, v in request.__dict__.items():
         assert v == request2.__dict__[k]
-
-def test_request_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.SetConfigRequest.from_payload(INVALID_PROTOBUF_MESSAGE)
-
-def test_response_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.SetConfigResponse.from_payload(INVALID_PROTOBUF_MESSAGE)

tests/test_set_scratchpad_target.py

@@ -1,10 +1,8 @@
 # flake8: noqa
 
-import pytest
 import wirepas_mesh_messaging
 import enum
 from default_value import *
-from wirepas_mesh_messaging.wirepas_exceptions import GatewayAPIParsingException
 
 
 def test_generate_parse_request_with_raw():
@@ -64,11 +62,3 @@ def test_generate_parse_response():
             assert v.value == request2.__dict__[k].value
         else:
             assert v == request2.__dict__[k]
-
-def test_request_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.SetScratchpadTargetAndActionRequest.from_payload(INVALID_PROTOBUF_MESSAGE)
-
-def test_response_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.SetScratchpadTargetAndActionResponse.from_payload(INVALID_PROTOBUF_MESSAGE)

tests/test_status.py

@@ -1,9 +1,7 @@
 # flake8: noqa
 
-import pytest
 import wirepas_mesh_messaging
 from default_value import *
-from wirepas_mesh_messaging.wirepas_exceptions import GatewayAPIParsingException
 
 DUMMY_CONFIGS = [NODE_CONFIG_1, NODE_CONFIG_2]
 
@@ -30,7 +28,3 @@ def test_generate_parse_event_with_max_size():
 
     for k, v in status.__dict__.items():
         assert v == status2.__dict__[k]
-
-def test_event_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.StatusEvent.from_payload(INVALID_PROTOBUF_MESSAGE)

tests/test_upload_scratchpad.py

@@ -1,9 +1,7 @@
 # flake8: noqa
 
-import pytest
 import wirepas_mesh_messaging
 from default_value import *
-from wirepas_mesh_messaging.wirepas_exceptions import GatewayAPIParsingException
 
 
 def test_generate_parse_request_clear():
@@ -54,11 +52,3 @@ def test_generate_parse_response():
 
     for k, v in request.__dict__.items():
         assert v == request2.__dict__[k]
-
-def test_request_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.UploadScratchpadRequest.from_payload(INVALID_PROTOBUF_MESSAGE)
-
-def test_response_decoding_error():
-    with pytest.raises(GatewayAPIParsingException):
-        wirepas_mesh_messaging.UploadScratchpadResponse.from_payload(INVALID_PROTOBUF_MESSAGE)

wirepas_mesh_messaging/wirepas_exceptions.py

@@ -12,3 +12,8 @@ class GatewayAPIParsingException(Exception):
     """
     Wirepas Gateway API generic Exception
     """
+
+class InvalidMessageType(GatewayAPIParsingException):
+    """
+    Exception indicating wrong message type during deserialization
+    """

wirepas_mesh_messaging/wirepas_message.py

@@ -10,7 +10,7 @@
 from abc import ABC, abstractmethod
 
 from .proto import GenericMessage
-from .wirepas_exceptions import GatewayAPIParsingException
+from .wirepas_exceptions import GatewayAPIParsingException, InvalidMessageType
 
 
 class WirepasMessage(ABC):
@@ -67,4 +67,11 @@ def _decode_and_get_related_message(cls, payload):
 
         contained_message = cls._get_related_message(generic_message)
 
+        # Works by checking if all required fields of contained_message are
+        # set. In our case, every message holds a required header field.
+        if not contained_message.IsInitialized():
+            raise InvalidMessageType(
+                f"Could not find relevant Wirepas message for {cls.__name__}"
+            )
+
         return contained_message