feat(api): add module emulation (#7353)

* magdeck

* tempdeck

* thermocycler

* app

* basic integration tests for modules.

* a little clean up and file renaming.

* skip thermocycler tests on windows.

* add very basic smoothie

* add comment about emulation fixture.

* add comment about naive regular expression.

* fix broken tests

api/src/opentrons/drivers/serial_communication.py

@@ -15,7 +15,7 @@ class SerialNoResponse(Exception):
 
 
 def get_ports_by_name(device_name):
-    '''Returns all serial devices with a given name'''
+    """Returns all serial devices with a given name"""
     filtered_devices = filter(
         lambda device: device_name in device[1],
         list_ports.comports()
@@ -25,15 +25,15 @@ def get_ports_by_name(device_name):
 
 
 def get_port_by_VID(vid):
-    '''Returns first serial device with a given VID'''
+    """Returns first serial device with a given VID"""
     for d in list_ports.comports():
         if d.vid == vid:
             return d[0]
 
 
 @contextlib.contextmanager
 def serial_with_temp_timeout(serial_connection, timeout):
-    '''Implements a temporary timeout for a serial connection'''
+    """Implements a temporary timeout for a serial connection"""
     saved_timeout = serial_connection.timeout
     if timeout is not None:
         serial_connection.timeout = timeout
@@ -56,10 +56,10 @@ def clear_buffer(serial_connection):
 
 
 def _write_to_device_and_return(cmd, ack, device_connection, tag=None):
-    '''Writes to a serial device.
+    """Writes to a serial device.
     - Formats command
     - Wait for ack return
-    - return parsed response'''
+    - return parsed response"""
 
     if not tag:
         tag = device_connection.port
@@ -82,8 +82,8 @@ def _write_to_device_and_return(cmd, ack, device_connection, tag=None):
 
 
 def _connect(port_name, baudrate):
-    ser = serial.Serial(
-        port=port_name,
+    ser = serial.serial_for_url(
+        url=port_name,
         baudrate=baudrate,
         timeout=DEFAULT_SERIAL_TIMEOUT
     )
@@ -92,7 +92,7 @@ def _connect(port_name, baudrate):
 
 
 def _attempt_command_recovery(command, ack, serial_conn, tag=None):
-    '''Recovery after following a failed write_and_return() atempt'''
+    """Recovery after following a failed write_and_return() attempt"""
     if not tag:
         tag = serial_conn.port
     with serial_with_temp_timeout(serial_conn, RECOVERY_TIMEOUT) as device:
@@ -109,7 +109,7 @@ def _attempt_command_recovery(command, ack, serial_conn, tag=None):
 def write_and_return(
         command, ack, serial_connection,
         timeout=DEFAULT_WRITE_TIMEOUT, tag=None):
-    '''Write a command and return the response'''
+    """Write a command and return the response"""
     clear_buffer(serial_connection)
     with serial_with_temp_timeout(
             serial_connection, timeout) as device_connection:
@@ -119,12 +119,12 @@ def write_and_return(
 
 
 def connect(device_name=None, port=None, baudrate=115200):
-    '''
+    """
     Creates a serial connection
     :param device_name: defaults to 'Smoothieboard'
     :param baudrate: integer frequency for serial communication
     :return: serial.Serial connection
-    '''
+    """
     if not port:
         port = get_ports_by_name(device_name=device_name)[0]
     log.debug("Device name: {}, Port: {}".format(device_name, port))

api/src/opentrons/drivers/thermocycler/driver.py

@@ -190,6 +190,8 @@ async def enter_programming_mode(self):
 
 
 class TCPoller(threading.Thread):
+    POLLING_FD_PATH = '/var/run/'
+
     def __init__(self, port, interrupt_callback, temp_status_callback,
                  lid_status_callback, lid_temp_status_callback):
         if not select:
@@ -206,14 +208,16 @@ def __init__(self, port, interrupt_callback, temp_status_callback,
         # Note: the options and order of operations for opening file
         # descriptors is very specific. For more info, see:
         # http://pubs.opengroup.org/onlinepubs/007908799/xsh/open.html
-        self._send_path = '/var/run/tc_send_fifo_{}'.format(hash(self))
+        self._send_path = os.path.join(
+            self.POLLING_FD_PATH, f"tc_send_fifo_{hash(self)}")
         os.mkfifo(self._send_path)
         send_read_fd = os.open(
             self._send_path, flags=os.O_RDONLY | os.O_NONBLOCK)
         self._send_read_file = os.fdopen(send_read_fd, 'rb')
         self._send_write_fd = open(self._send_path, 'wb', buffering=0)
 
-        self._halt_path = '/var/run/tc_halt_fifo_{}'.format(hash(self))
+        self._halt_path = os.path.join(
+            self.POLLING_FD_PATH, f"tc_halt_fifo_{hash(self)}")
         os.mkfifo(self._halt_path)
         halt_read_fd = os.open(
             self._halt_path, flags=os.O_RDONLY | os.O_NONBLOCK)

api/src/opentrons/hardware_control/emulation/app.py

@@ -0,0 +1,98 @@
+import asyncio
+import re
+import logging
+
+from opentrons.hardware_control.emulation.magdeck import MagDeckEmulator
+from opentrons.hardware_control.emulation.tempdeck import TempDeckEmulator
+from opentrons.hardware_control.emulation.thermocycler import ThermocyclerEmulator
+from opentrons.hardware_control.emulation.smoothie import SmoothieEmulator
+
+from .command_processor import CommandProcessor
+
+logger = logging.getLogger(__name__)
+
+
+SMOOTHIE_PORT = 9996
+THERMOCYCLER_PORT = 9997
+TEMPDECK_PORT = 9998
+MAGDECK_PORT = 9999
+
+
+LINE_REGEX = re.compile(r"(\S+)(.+)")
+"""Split the line into command and payload.
+
+TODO AL 20210222 This regex is a very naive approach and should be revisited
+ if we are going to expand emulator support.
+We can use a regex like "[A-Z][0-9]+\\.*[0-9]*" to match gcodes (i think). And
+handle our custom directives like 'version' and 'dfu' separately.
+"""
+
+
+class ConnectionHandler:
+    def __init__(self, command_processor: CommandProcessor,
+                 terminator: bytes = b'\r\n\r\n',
+                 ack: bytes = b'ok\r\nok\r\n'):
+        """Construct"""
+        self._command_processor = command_processor
+        self._terminator = terminator
+        self._ack = ack
+
+    async def __call__(self, reader: asyncio.StreamReader,
+                       writer: asyncio.StreamWriter) -> None:
+        """New connection callback."""
+        logger.debug("Connected.")
+        while True:
+            line = await reader.readuntil(self._terminator)
+            logger.debug("Received: %s", line)
+
+            m = LINE_REGEX.match(line.decode())
+            if m:
+                groups = m.groups()
+                cmd = groups[0]
+                payload = groups[1]
+                logger.debug("Command: %s, Payload: %s", cmd, payload)
+                response = self._command_processor.handle(cmd, payload)
+                if response:
+                    response = f'{response}\r\n'
+                    logger.debug("Sending: %s", response)
+                    writer.write(response.encode())
+
+            writer.write(self._ack)
+            await writer.drain()
+
+
+async def run_server(host: str, port: int, handler: ConnectionHandler) -> None:
+    """Run a server."""
+    server = await asyncio.start_server(handler, host, port)
+
+    async with server:
+        await server.serve_forever()
+
+
+async def run() -> None:
+    """Run the module emulators."""
+    host = "127.0.0.1"
+
+    await asyncio.gather(
+        run_server(host=host,
+                   port=MAGDECK_PORT,
+                   handler=ConnectionHandler(MagDeckEmulator())),
+        run_server(host=host,
+                   port=TEMPDECK_PORT,
+                   handler=ConnectionHandler(TempDeckEmulator())),
+        run_server(host=host,
+                   port=THERMOCYCLER_PORT,
+                   handler=ConnectionHandler(ThermocyclerEmulator(),
+                                             terminator=b'\r\n')),
+        run_server(host=host,
+                   port=SMOOTHIE_PORT,
+                   handler=ConnectionHandler(SmoothieEmulator())),
+    )
+
+
+if __name__ == "__main__":
+    h = logging.StreamHandler()
+    h.setLevel(logging.DEBUG)
+    logger.setLevel(logging.DEBUG)
+    logger.addHandler(h)
+    asyncio.run(run())

api/src/opentrons/hardware_control/emulation/command_processor.py

@@ -0,0 +1,11 @@
+from abc import ABC, abstractmethod
+from typing import Optional
+
+
+class CommandProcessor(ABC):
+    """Interface of gcode command processor."""
+
+    @abstractmethod
+    def handle(self, cmd: str, payload: str) -> Optional[str]:
+        """Handle a command and return a response."""
+        ...

api/src/opentrons/hardware_control/emulation/magdeck.py

@@ -0,0 +1,45 @@
+import logging
+from typing import Optional
+from opentrons.drivers.mag_deck.driver import GCODES
+from .command_processor import CommandProcessor
+
+logger = logging.getLogger(__name__)
+
+GCODE_HOME = GCODES['HOME']
+GCODE_MOVE = GCODES['MOVE']
+GCODE_PROBE = GCODES['PROBE_PLATE']
+GCODE_GET_PROBED_DISTANCE = GCODES['GET_PLATE_HEIGHT']
+GCODE_GET_POSITION = GCODES['GET_CURRENT_POSITION']
+GCODE_DEVICE_INFO = GCODES['DEVICE_INFO']
+GCODE_DFU = GCODES['PROGRAMMING_MODE']
+
+SERIAL = "fake_serial"
+MODEL = "magdeck_emulator"
+VERSION = 1
+
+
+class MagDeckEmulator(CommandProcessor):
+    """Magdeck emulator"""
+
+    def __init__(self) -> None:
+        self.height = 0
+        self.position = 0
+
+    def handle(self, cmd: str, payload: str) -> Optional[str]:
+        """Handle a command."""
+        logger.info(f"Got command {cmd}")
+        if cmd == GCODE_HOME:
+            pass
+        elif cmd == GCODE_MOVE:
+            pass
+        elif cmd == GCODE_PROBE:
+            pass
+        elif cmd == GCODE_GET_PROBED_DISTANCE:
+            return f"height:{self.height}"
+        elif cmd == GCODE_GET_POSITION:
+            return f"Z:{self.position}"
+        elif cmd == GCODE_DEVICE_INFO:
+            return f"serial:{SERIAL} model:{MODEL} version:{VERSION}"
+        elif cmd == GCODE_DFU:
+            pass
+        return None

api/src/opentrons/hardware_control/emulation/smoothie.py

@@ -0,0 +1,58 @@
+import logging
+from typing import Optional
+
+from opentrons.drivers.smoothie_drivers.driver_3_0 import GCODES
+
+from .command_processor import CommandProcessor
+
+logger = logging.getLogger(__name__)
+
+GCODE_HOME = GCODES['HOME']
+GCODE_MOVE = GCODES['MOVE']
+GCODE_DWELL = GCODES['DWELL']
+GCODE_CURRENT_POSITION = GCODES['CURRENT_POSITION']
+GCODE_LIMIT_SWITCH_STATUS = GCODES['LIMIT_SWITCH_STATUS']
+GCODE_PROBE = GCODES['PROBE']
+GCODE_ABSOLUTE_COORDS = GCODES['ABSOLUTE_COORDS']
+GCODE_RELATIVE_COORDS = GCODES['RELATIVE_COORDS']
+GCODE_RESET_FROM_ERROR = GCODES['RESET_FROM_ERROR']
+GCODE_PUSH_SPEED = GCODES['PUSH_SPEED']
+GCODE_POP_SPEED = GCODES['POP_SPEED']
+GCODE_SET_SPEED = GCODES['SET_SPEED']
+GCODE_STEPS_PER_MM = GCODES['STEPS_PER_MM']
+GCODE_READ_INSTRUMENT_ID = GCODES['READ_INSTRUMENT_ID']
+GCODE_WRITE_INSTRUMENT_ID = GCODES['WRITE_INSTRUMENT_ID']
+GCODE_READ_INSTRUMENT_MODEL = GCODES['READ_INSTRUMENT_MODEL']
+GCODE_WRITE_INSTRUMENT_MODEL = GCODES['WRITE_INSTRUMENT_MODEL']
+GCODE_SET_MAX_SPEED = GCODES['SET_MAX_SPEED']
+GCODE_SET_CURRENT = GCODES['SET_CURRENT']
+GCODE_DISENGAGE_MOTOR = GCODES['DISENGAGE_MOTOR']
+GCODE_HOMING_STATUS = GCODES['HOMING_STATUS']
+GCODE_ACCELERATION = GCODES['ACCELERATION']
+GCODE_WAIT = GCODES['WAIT']
+GCODE_retract = 'M365.3'
+GCODE_debounce = 'M365.2'
+GCODE_max_travel = 'M365.1'
+GCODE_home = 'M365.0'
+GCODE_version = 'version'
+
+v = """Build version: EMULATOR, Build date: CURRENT, MCU: NONE, System Clock: NONE"""
+
+
+class SmoothieEmulator(CommandProcessor):
+    """Smoothie emulator"""
+
+    def __init__(self) -> None:
+        self.x = self.y = self.z = self.a = self.b = self.c = 0.00
+
+    def handle(self, cmd: str, payload: str) -> Optional[str]:
+        """Handle a command."""
+        logger.info(f"Got command {cmd}")
+        if GCODE_HOMING_STATUS == cmd:
+            return "X:0 Y:0 Z:0 A:0 B:0 C:0"
+        elif GCODE_CURRENT_POSITION == cmd:
+            return f"{cmd}\r\n\r\nok MCS: X:{self.x} Y:{self.y} " \
+                   f"Z:{self.z} A:{self.a} B:{self.b} C:{self.c}"
+        elif GCODE_version == cmd:
+            return v
+        return None

api/src/opentrons/hardware_control/emulation/tempdeck.py

@@ -0,0 +1,41 @@
+import logging
+from typing import Optional
+
+from opentrons.drivers.temp_deck.driver import GCODES
+
+from .command_processor import CommandProcessor
+
+logger = logging.getLogger(__name__)
+
+GCODE_GET_TEMP = GCODES['GET_TEMP']
+GCODE_SET_TEMP = GCODES['SET_TEMP']
+GCODE_DEVICE_INFO = GCODES['DEVICE_INFO']
+GCODE_DISENGAGE = GCODES['DISENGAGE']
+GCODE_DFU = GCODES['PROGRAMMING_MODE']
+
+SERIAL = "fake_serial"
+MODEL = "temp_emulator"
+VERSION = 1
+
+
+class TempDeckEmulator(CommandProcessor):
+    """TempDeck emulator"""
+
+    def __init__(self) -> None:
+        self.target_temp = 0
+        self.current_temp = 0
+
+    def handle(self, cmd: str, payload: str) -> Optional[str]:
+        """Handle a command."""
+        logger.info(f"Got command {cmd}")
+        if cmd == GCODE_GET_TEMP:
+            return f"T:{self.target_temp} C:{self.current_temp}"
+        elif cmd == GCODE_SET_TEMP:
+            pass
+        elif cmd == GCODE_DISENGAGE:
+            pass
+        elif cmd == GCODE_DEVICE_INFO:
+            return f"serial:{SERIAL} model:{MODEL} version:{VERSION}"
+        elif cmd == GCODE_DFU:
+            pass
+        return None