def test_write_float(self):
value = 123.456
ads.write(self.endpoint,
index_group=constants.INDEXGROUP_DATA,
index_offset=1,
value=value,
plc_datatype=constants.PLCTYPE_REAL)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Assert that the server received a request
self.assertEqual(len(requests), 1)
# Assert that the server received the correct command
self.assert_command_id(requests[0], constants.ADSCOMMAND_WRITE)
# Check the value received by the server
received_value = struct.unpack('<f',
requests[0].ams_header.data[12:])[0]
# Pythons internal representation of a float has a higher precision
# than 32 bits, so will be more precise than the value received by the
# server. To do a comparison we must put the initial 'write' value
# through the round-trip of converting to 32-bit precision.
value_32 = struct.unpack('<f', struct.pack('<f', value))[0]
self.assertEqual(value_32, received_value)
def test_write_string(self):
value = "Test String 1234."
ads.write(self.endpoint,
index_group=constants.INDEXGROUP_DATA,
index_offset=1,
value=value,
plc_datatype=constants.PLCTYPE_STRING)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Assert that the server received a request
self.assertEqual(len(requests), 1)
# Assert that the server received the correct command
self.assert_command_id(requests[0], constants.ADSCOMMAND_WRITE)
# Check the value received by the server
received_value = requests[0].ams_header.data[12:]
# String should have been sent null terminated
sent_value = (value + '\x00').encode('utf-8')
self.assertEqual(sent_value, received_value)
def test_read_check_length(self):
# Write data shorter than what should be read
ads.write(
self.endpoint,
value=1,
index_group=constants.INDEXGROUP_DATA,
index_offset=1,
plc_datatype=constants.PLCTYPE_USINT,
)
with self.assertRaises(RuntimeError):
# Since the length is checked, this must give an error
ads.read(
self.endpoint,
index_group=constants.INDEXGROUP_DATA,
index_offset=1,
plc_datatype=constants.PLCTYPE_UINT,
check_length=True,
)
# If the length is not checked, no error should be raised
value = ads.read(
self.endpoint,
index_group=constants.INDEXGROUP_DATA,
index_offset=1,
plc_datatype=constants.PLCTYPE_UINT,
check_length=False,
)
self.assertEqual(value, 1)
def test_write_uint(self):
value = 100
ads.write(
self.endpoint,
index_group=constants.INDEXGROUP_DATA,
index_offset=1,
value=value,
plc_datatype=constants.PLCTYPE_UDINT,
)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Assert that the server received a request
self.assertEqual(len(requests), 1)
# Assert that the server received the correct command
self.assert_command_id(requests[0], constants.ADSCOMMAND_WRITE)
# Check the value received by the server
received_value = struct.unpack("<I",
requests[0].ams_header.data[12:])[0]
self.assertEqual(value, received_value)
def test_write_float(self):
value = 123.456
ads.write(
self.endpoint, index_group=constants.INDEXGROUP_DATA,
index_offset=1, value=value, plc_datatype=constants.PLCTYPE_REAL
)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Assert that the server received a request
self.assertEqual(len(requests), 1)
# Assert that the server received the correct command
self.assert_command_id(requests[0], constants.ADSCOMMAND_WRITE)
# Check the value received by the server
received_value = struct.unpack('<f', requests[0].ams_header.data[12:])[0]
# Pythons internal representation of a float has a higher precision
# than 32 bits, so will be more precise than the value received by the
# server. To do a comparison we must put the initial 'write' value
# through the round-trip of converting to 32-bit precision.
value_32 = struct.unpack('<f', struct.pack('<f', value))[0]
self.assertEqual(value_32, received_value)
def test_write_array(self):
write_value = tuple(range(5))
ads.write(
self.endpoint, index_group=constants.INDEXGROUP_DATA, index_offset=1,
value=write_value, plc_datatype=constants.PLCTYPE_UDINT * 5
)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Check the value received by the server
received_value = struct.unpack('<IIIII', requests[0].ams_header.data[12:])
self.assertEqual(write_value, received_value)
def test_write_array(self):
write_value = tuple(range(5))
ads.write(self.endpoint,
index_group=constants.INDEXGROUP_DATA,
index_offset=1,
value=write_value,
plc_datatype=constants.PLCTYPE_UDINT * 5)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Check the value received by the server
received_value = struct.unpack('<IIIII',
requests[0].ams_header.data[12:])
self.assertEqual(write_value, received_value)
def test_write_struct(self):
write_value = _Struct(-123, 456)
ads.write(
self.endpoint,
index_group=constants.INDEXGROUP_DATA,
index_offset=1,
value=write_value,
plc_datatype=_Struct,
)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Check the value received by the server
received_value = _Struct.from_buffer_copy(requests[0].ams_header.data[12:])
self.assertEqual(write_value.x, received_value.x)
self.assertEqual(write_value.y, received_value.y)
def test_write_uint(self):
value = 100
ads.write(
self.endpoint, index_group=constants.INDEXGROUP_DATA,
index_offset=1, value=value, plc_datatype=constants.PLCTYPE_UDINT
)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Assert that the server received a request
self.assertEqual(len(requests), 1)
# Assert that the server received the correct command
self.assert_command_id(requests[0], constants.ADSCOMMAND_WRITE)
# Check the value received by the server
received_value = struct.unpack('<I', requests[0].ams_header.data[12:])[0]
self.assertEqual(value, received_value)
def test_write_string(self):
value = "Test String 1234."
ads.write(
self.endpoint, index_group=constants.INDEXGROUP_DATA,
index_offset=1, value=value, plc_datatype=constants.PLCTYPE_STRING
)
# Retrieve list of received requests from server
requests = self.test_server.request_history
# Assert that the server received a request
self.assertEqual(len(requests), 1)
# Assert that the server received the correct command
self.assert_command_id(requests[0], constants.ADSCOMMAND_WRITE)
# Check the value received by the server
received_value = requests[0].ams_header.data[12:]
# String should have been sent null terminated
sent_value = (value + '\x00').encode('utf-8')
self.assertEqual(sent_value, received_value)
