scicam_camd

#!/usr/bin/env python3
#
# This file is part of the Robotic Observatory Control Kit (rockit)
#
# rockit is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# rockit is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with rockit.  If not, see <http://www.gnu.org/licenses/>.

"""Daemon for controlling a Princeton IR SciCam 1280 via Pyro"""

# pylint: disable=too-many-arguments
# pylint: disable=too-many-return-statements
# pylint: disable=too-many-instance-attributes
# pylint: disable=too-many-lines
# pylint: disable=too-many-branches
# pylint: disable=too-many-statements

import argparse
from ctypes import c_bool
from multiprocessing import Process, Queue, Value, Pipe
from multiprocessing.sharedctypes import RawArray
import queue
import threading
import Pyro4
from rockit.common import TryLock
from rockit.common.helpers import pyro_client_matches
from rockit.camera.scicam import Config, CommandStatus, CameraStatus, output_process, scicam_process


class CameraDaemon:
    """Daemon interface for andor camera"""
    def __init__(self, config):
        self._config = config
        self._command_lock = threading.Lock()

        self._cam_process = self._cam_pipe = None
        self._cam_lock = threading.Lock()

        # Subprocesses for processing acquired frames
        self._processing_queue = Queue()
        self._processing_framebuffer = RawArray('B', config.framebuffer_bytes)
        self._processing_framebuffer_offsets = Queue()
        self._processing_stop_signal = Value(c_bool, False)

        for _ in range(config.worker_processes):
            Process(target=output_process, daemon=True, args=(
                self._processing_queue, self._processing_framebuffer, self._processing_framebuffer_offsets,
                self._processing_stop_signal, config.camera_id,
                config.header_card_capacity, config.output_path, config.log_name,
                config.pipeline_daemon_name, config.pipeline_handover_timeout)).start()

    def cam_command(self, command, oneway=False, **kwargs):
        """Send a command to the camera process and return the response"""
        with self._cam_lock:
            if self._cam_process is None or not self._cam_process.is_alive():
                return CommandStatus.CameraNotInitialized

            self._cam_pipe.send({
                'command': command,
                'args': kwargs
            })

            if oneway:
                return CommandStatus.Succeeded

            return self._cam_pipe.recv()

    @Pyro4.expose
    def initialize(self):
        """Connects to the camera driver"""
        if not pyro_client_matches(self._config.control_ips):
            return CommandStatus.InvalidControlIP

        with TryLock(self._command_lock) as success:
            if not success:
                return CommandStatus.Blocked

            with self._cam_lock:
                if self._cam_process is not None and self._cam_process.is_alive():
                    return CommandStatus.CameraNotUninitialized

                self._cam_pipe, camd_pipe = Pipe()
                self._cam_process = Process(target=scicam_process, args=(
                    camd_pipe, self._config,
                    self._processing_queue,
                    self._processing_framebuffer, self._processing_framebuffer_offsets,
                    self._processing_stop_signal
                ), daemon=True)

                self._cam_process.start()
                return self._cam_pipe.recv()

    @Pyro4.expose
    def shutdown(self):
        """Disconnects from the camera driver"""
        if not pyro_client_matches(self._config.control_ips):
            return CommandStatus.InvalidControlIP

        with TryLock(self._command_lock) as success:
            if not success:
                return CommandStatus.Blocked

            if self._cam_process is None:
                return CommandStatus.CameraNotInitialized

            self.cam_command('shutdown', oneway=True)

            with self._cam_lock:
                # The pyro timeout is usually set to 5s,
                # so allow a little time to terminate the process if needed
                self._cam_process.join(4.5)
                if self._cam_process.exitcode is None:
                    print('force-terminating Raptor process')
                    self._cam_process.terminate()

                    # Clean up dirty state
                    while not self._processing_queue.empty():
                        try:
                            self._processing_queue.get(block=False)
                        except queue.Empty:
                            continue

                    while not self._processing_framebuffer_offsets.empty():
                        try:
                            self._processing_framebuffer_offsets.get(block=False)
                        except queue.Empty:
                            continue

            return CommandStatus.Succeeded

    @Pyro4.expose
    def report_status(self):
        """Returns a dictionary containing the current camera state"""
        data = self.cam_command('status')
        if isinstance(data, dict):
            return data

        return {'state': CameraStatus.Disabled}

    @Pyro4.expose
    def set_target_temperature(self, temperature, quiet=False):
        """Set the target camera temperature"""
        if not pyro_client_matches(self._config.control_ips):
            return CommandStatus.InvalidControlIP

        with TryLock(self._command_lock) as success:
            if not success:
                return CommandStatus.Blocked

            return self.cam_command('temperature', temperature=temperature, quiet=quiet)

    @Pyro4.expose
    def set_exposure(self, seconds, quiet=False):
        """Set the exposure time in seconds"""
        if not pyro_client_matches(self._config.control_ips):
            return CommandStatus.InvalidControlIP

        with TryLock(self._command_lock) as success:
            if not success:
                return CommandStatus.Blocked

            return self.cam_command('exposure', exposure=seconds, quiet=quiet)

    @Pyro4.expose
    def configure(self, params, quiet=False):
        """Set camera configuration to the requested state
           params should be a dictionary with the following keys:
              temperature: Temperature set point
              exposure: Exposure time in seconds
           Any properties not specified in params will be reset to its default

           The params dictionary should be validated using the
           schema returned by the configure_validation_schema helper

            Set quiet=True to disable log messages
        """
        if not pyro_client_matches(self._config.control_ips):
            return CommandStatus.InvalidControlIP

        with TryLock(self._command_lock) as success:
            if not success:
                return CommandStatus.Blocked

            temperature = params.get('temperature', self._config.cooler_setpoint)
            self.cam_command('temperature', temperature=temperature, quiet=quiet)

            exposure = params.get('exposure', 1)
            self.cam_command('exposure', exposure=exposure, quiet=quiet)

            return CommandStatus.Succeeded

    @Pyro4.expose
    def start_sequence(self, count, quiet=False):
        """Starts an exposure sequence with a set number of frames, or 0 to run until stopped"""
        if not pyro_client_matches(self._config.control_ips):
            return CommandStatus.InvalidControlIP

        with TryLock(self._command_lock) as success:
            if not success:
                return CommandStatus.Blocked

            return self.cam_command('start', count=count, quiet=quiet)

    @Pyro4.expose
    def stop_sequence(self, quiet=False):
        """Stops any active exposure sequence"""
        if not pyro_client_matches(self._config.control_ips):
            return CommandStatus.InvalidControlIP

        return self.cam_command('stop', quiet=quiet)


if __name__ == '__main__':
    parser = argparse.ArgumentParser(description='Camera control daemon')
    parser.add_argument('config', help='Path to configuration json file')
    args = parser.parse_args()
    c = Config(args.config)
    c.daemon.launch(CameraDaemon(c))