def test_read_structure_by_name(self):
# type: () -> None
"""Test read by structure method"""
# TODO may need testserver.py changes to increase test usefulness
handle_name = "TestHandle"
structure_def = (("xVar", pyads.PLCTYPE_BYTE, 1),)
# test with no structure size passed in
with self.plc:
read_value = self.plc.read_structure_by_name(handle_name, structure_def)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Assert that the server received 3 requests
self.assertEqual(len(requests), 3)
# Assert that Read/Write command was used to get the handle by name
self.assert_command_id(requests[0], constants.ADSCOMMAND_READWRITE)
# Assert that the server received the handle by name
received_value = requests[0].ams_header.data[16:]
sent_value = (handle_name + "\x00").encode("utf-8")
self.assertEqual(sent_value, received_value)
# Assert that next, the Read command was used to get the value
self.assert_command_id(requests[1], constants.ADSCOMMAND_READ)
# Assert that Write was used to release the handle
self.assert_command_id(requests[2], constants.ADSCOMMAND_WRITE)
# Check read value returned by server:
# Test server just returns repeated bytes of 0x0F terminated with 0x00
# But because the read value is only 1-byte long, we just get 0x00
expected_result = OrderedDict([("xVar", 0)])
self.assertEqual(read_value, expected_result)
# Test with structure size passed in
structure_size = pyads.size_of_structure(structure_def)
with self.plc:
read_value = self.plc.read_structure_by_name(
handle_name, structure_def, structure_size=structure_size
)
self.assertEqual(read_value, expected_result)
# Test with handle passed in
with self.plc:
handle = self.plc.get_handle(handle_name)
read_value = self.plc.read_structure_by_name(
"", structure_def, handle=handle
)
self.assertEqual(read_value, expected_result)
with self.plc:
self.plc.release_handle(handle)
def test_write_structure_by_name(self):
# type: () -> None
"""Test write by structure method"""
handle_name = "TestHandle"
struct_to_write = OrderedDict([("sVar", "Test Value")])
value = "Test Value"
structure_def = (("sVar", pyads.PLCTYPE_STRING, 1),)
# test with no structure size passed in
with self.plc:
self.plc.write_structure_by_name(handle_name, struct_to_write, structure_def)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Assert that the server received 3 requests
self.assertEqual(len(requests), 3)
# Assert that Read/Write command was used to get the handle by name
self.assert_command_id(requests[0], constants.ADSCOMMAND_READWRITE)
# Assert that Write command was used to write the value
self.assert_command_id(requests[1], constants.ADSCOMMAND_WRITE)
# Check the value written matches our value
received_value = requests[1].ams_header.data[12:].decode("utf-8").rstrip("\x00")
self.assertEqual(value, received_value)
# Assert that Write was used to release the handle
self.assert_command_id(requests[2], constants.ADSCOMMAND_WRITE)
# Test with structure size passed in
structure_size = pyads.size_of_structure(structure_def)
with self.plc:
self.plc.write_structure_by_name(
handle_name, struct_to_write, structure_def, structure_size=structure_size
)
requests = self.test_server.request_history
received_value = requests[1].ams_header.data[12:].decode("utf-8").rstrip("\x00")
self.assertEqual(value, received_value)
# Test with handle passed in
with self.plc:
handle = self.plc.get_handle(handle_name)
self.plc.write_structure_by_name("", struct_to_write, structure_def, handle=handle)
requests = self.test_server.request_history
received_value = requests[1].ams_header.data[12:].decode("utf-8").rstrip("\x00")
self.assertEqual(value, received_value)
with self.plc:
self.plc.release_handle(handle)
def test_size_of_structure(self):
# type: () -> None
"""Test size_of_structure function"""
# known structure size with defined string
structure_def = (
("rVar", pyads.PLCTYPE_LREAL, 1),
("sVar", pyads.PLCTYPE_STRING, 2, 35),
("rVar1", pyads.PLCTYPE_REAL, 4),
("iVar", pyads.PLCTYPE_DINT, 5),
("iVar1", pyads.PLCTYPE_INT, 3),
("ivar2", pyads.PLCTYPE_UDINT, 6),
("iVar3", pyads.PLCTYPE_UINT, 7),
("iVar4", pyads.PLCTYPE_BYTE, 1),
("iVar5", pyads.PLCTYPE_SINT, 1),
("iVar6", pyads.PLCTYPE_USINT, 1),
("bVar", pyads.PLCTYPE_BOOL, 4),
("iVar7", pyads.PLCTYPE_WORD, 1),
("iVar8", pyads.PLCTYPE_DWORD, 1),
)
self.assertEqual(pyads.size_of_structure(structure_def), 173)
# test for PLC_DEFAULT_STRING_SIZE
structure_def = (("sVar", pyads.PLCTYPE_STRING, 4), )
self.assertEqual(
pyads.size_of_structure(structure_def),
(pyads.PLC_DEFAULT_STRING_SIZE + 1) * 4,
)
# tests for incorrect definitions
structure_def = (
("sVar", pyads.PLCTYPE_STRING, 4),
("rVar", 1, 1),
("iVar", pyads.PLCTYPE_DINT, 1),
)
with self.assertRaises(RuntimeError):
pyads.size_of_structure(structure_def)
structure_def = (
("sVar", pyads.PLCTYPE_STRING, 4),
(pyads.PLCTYPE_REAL, 1),
("iVar", pyads.PLCTYPE_DINT, 1),
)
with self.assertRaises(ValueError):
pyads.size_of_structure(structure_def)
structure_def = (
("sVar", pyads.PLCTYPE_STRING, 4),
("rVar", pyads.PLCTYPE_REAL, ""),
("iVar", pyads.PLCTYPE_DINT, 1),
("iVar1", pyads.PLCTYPE_INT, 3),
)
with self.assertRaises(TypeError):
pyads.size_of_structure(structure_def)
# test another correct definition with array of structure
structure_def = (
("bVar", pyads.PLCTYPE_BOOL, 1),
("rVar", pyads.PLCTYPE_LREAL, 3),
("sVar", pyads.PLCTYPE_STRING, 2),
("iVar", pyads.PLCTYPE_DINT, 10),
("iVar1", pyads.PLCTYPE_INT, 3),
("bVar1", pyads.PLCTYPE_BOOL, 4),
)
self.assertEqual(pyads.size_of_structure(structure_def * 5), 1185)
