Use specific exceptions for AT command responses (#169)

Author: Shulyaka

tests/test_api.py

@@ -10,6 +10,7 @@
 
 from zigpy_xbee import api as xbee_api, types as xbee_t, uart
 import zigpy_xbee.config
+from zigpy_xbee.exceptions import ATCommandError, ATCommandException, InvalidCommand
 from zigpy_xbee.zigbee.application import ControllerApplication
 
 import tests.async_mock as mock
@@ -327,7 +328,16 @@ def test_handle_at_response_error(api):
     status, response = 1, 0x23
     fut = _handle_at_response(api, tsn, status, [response])
     assert fut.done() is True
-    assert fut.exception() is not None
+    assert isinstance(fut.exception(), ATCommandError)
+
+
+def test_handle_at_response_invalid_command(api):
+    """Test invalid AT command response."""
+    tsn = 123
+    status, response = 2, 0x23
+    fut = _handle_at_response(api, tsn, status, [response])
+    assert fut.done() is True
+    assert isinstance(fut.exception(), InvalidCommand)
 
 
 def test_handle_at_response_undef_error(api):
@@ -336,7 +346,7 @@ def test_handle_at_response_undef_error(api):
     status, response = 0xEE, 0x23
     fut = _handle_at_response(api, tsn, status, [response])
     assert fut.done() is True
-    assert fut.exception() is not None
+    assert isinstance(fut.exception(), ATCommandException)
 
 
 def test_handle_remote_at_rsp(api):

tests/test_application.py

@@ -11,6 +11,7 @@
 
 from zigpy_xbee.api import XBee
 import zigpy_xbee.config as config
+from zigpy_xbee.exceptions import InvalidCommand
 import zigpy_xbee.types as xbee_t
 from zigpy_xbee.zigbee import application
 
@@ -305,7 +306,7 @@ async def test_write_network_info(app, node_info, network_info, legacy_module):
 
     def _mock_queued_at(name, *args):
         if legacy_module and name == "CE":
-            raise RuntimeError("Legacy module")
+            raise InvalidCommand("Legacy module")
         return "OK"
 
     app._api._queued_at = mock.AsyncMock(
@@ -346,7 +347,7 @@ def _at_command_mock(cmd, *args):
         if not api_mode:
             raise asyncio.TimeoutError
         if cmd == "CE" and legacy_module:
-            raise RuntimeError
+            raise InvalidCommand
 
         ai_tries -= 1 if cmd == "AI" else 0
         return {

zigpy_xbee/api.py

@@ -2,7 +2,6 @@
 
 import asyncio
 import binascii
-import enum
 import functools
 import logging
 from typing import Any, Dict, Optional
@@ -13,6 +12,13 @@
 
 import zigpy_xbee
 from zigpy_xbee.config import CONF_DEVICE_BAUDRATE, CONF_DEVICE_PATH, SCHEMA_DEVICE
+from zigpy_xbee.exceptions import (
+    ATCommandError,
+    ATCommandException,
+    InvalidCommand,
+    InvalidParameter,
+    TransmissionFailure,
+)
 
 from . import types as xbee_t, uart
 
@@ -261,14 +267,12 @@
 }
 
 
-class ATCommandResult(enum.IntEnum):
-    """AT Command Result."""
-
-    OK = 0
-    ERROR = 1
-    INVALID_COMMAND = 2
-    INVALID_PARAMETER = 3
-    TX_FAILURE = 4
+AT_COMMAND_RESULT = {
+    1: ATCommandError,
+    2: InvalidCommand,
+    3: InvalidParameter,
+    4: TransmissionFailure,
+}
 
 
 class XBee:
@@ -444,13 +448,13 @@ def frame_received(self, data):
     def _handle_at_response(self, frame_id, cmd, status, value):
         """Local AT command response."""
         (fut,) = self._awaiting.pop(frame_id)
-        try:
-            status = ATCommandResult(status)
-        except ValueError:
-            status = ATCommandResult.ERROR
 
         if status:
-            fut.set_exception(RuntimeError(f"AT Command response: {status.name}"))
+            try:
+                exception = AT_COMMAND_RESULT[status]
+            except KeyError:
+                exception = ATCommandException
+            fut.set_exception(exception(f"AT Command response: {status}"))
             return
 
         response_type = AT_COMMANDS[cmd.decode("ascii")]

zigpy_xbee/exceptions.py

@@ -0,0 +1,21 @@
+"""Additional exceptions for XBee."""
+
+
+class ATCommandException(Exception):
+    """Base exception class for AT Command exceptions."""
+
+
+class ATCommandError(ATCommandException):
+    """Exception for AT Command Status 1 (ERROR)."""
+
+
+class InvalidCommand(ATCommandException):
+    """Exception for AT Command Status 2 (Invalid command)."""
+
+
+class InvalidParameter(ATCommandException):
+    """Exception for AT Command Status 3 (Invalid parameter)."""
+
+
+class TransmissionFailure(ATCommandException):
+    """Exception for Remote AT Command Status 4 (Transmission failure)."""

zigpy_xbee/zigbee/application.py

@@ -23,6 +23,7 @@
 import zigpy_xbee
 import zigpy_xbee.api
 from zigpy_xbee.config import CONF_DEVICE, CONFIG_SCHEMA, SCHEMA_DEVICE
+from zigpy_xbee.exceptions import InvalidCommand
 from zigpy_xbee.types import EUI64, UNKNOWN_IEEE, UNKNOWN_NWK, TXOptions, TXStatus
 
 # how long coordinator would hold message for an end device in 10ms units
@@ -131,7 +132,7 @@ async def load_network_info(self, *, load_devices=False):
                 node_info.logical_type = zdo_t.LogicalType.Coordinator
             else:
                 node_info.logical_type = zdo_t.LogicalType.EndDevice
-        except RuntimeError:
+        except InvalidCommand:
             LOGGER.warning("CE command failed, assuming node is coordinator")
             node_info.logical_type = zdo_t.LogicalType.Coordinator
 
@@ -171,7 +172,7 @@ async def write_network_info(self, *, network_info, node_info):
 
         try:
             await self._api._queued_at("CE", 1)
-        except RuntimeError:
+        except InvalidCommand:
             pass
 
         await self._api._at_command("WR")