fix: remove RPi.GPIO usage. Check for command existance and ignore if not available

Author: AlvinSchiller

src/jukebox/components/hostif/linux/__init__.py

@@ -10,27 +10,12 @@
 import jukebox.publishing
 import jukebox.speaking_text
 from jukebox.multitimer import GenericEndlessTimerClass
-import socket
 
 logger = logging.getLogger('jb.host.lnx')
 cfg = jukebox.cfghandler.get_handler('jukebox')
 # Get the main Thread Publisher
 publisher = jukebox.publishing.get_publisher()
 
-# This is a slightly dirty way of checking if we are on an RPi
-# JukeBox installs the dependency RPI which has no meaning on other machines
-# If it does not exist all is clear
-# It could still be installed, which results in a RuntimeError when loaded on a PC
-try:
-    import RPi.GPIO as gpio  # noqa: F401
-
-    IS_RPI = True
-except ModuleNotFoundError:
-    IS_RPI = False
-except RuntimeError as e:
-    logger.info(f"You don't seem to be on a PI, because loading 'RPi.GPIO' failed: {e.__class__.__name__}: {e}")
-    IS_RPI = False
-
 # In debug mode, shutdown and reboot command are not actually executed
 IS_DEBUG = False
 try:
@@ -302,73 +287,60 @@ def start_autohotspot():
         return 'not-installed'
 
 
-@plugin.initialize
-def initialize():
-    wlan_power = cfg.setndefault('host', 'wlan_power', 'disable_power_down', value=True)
-    card = cfg.setndefault('host', 'wlan_power', 'card', value='wlan0')
-    if wlan_power:
-        wlan_disable_power_down(card)
+# ---------------------------------------------------------------------------
+# RPi-only stuff
+# ---------------------------------------------------------------------------
+THROTTLE_CODES = {
+    0x1: "under-voltage detected",
+    0x2: "ARM frequency capped",
+    0x4: "currently throttled",
+    0x8: "soft temperature limit active",
+    0x10000: "under-voltage has occurred",
+    0x20000: "ARM frequency capped has occurred",
+    0x40000: "throttling has occurred",
+    0x80000: "soft temperature limit has occurred"
+}
 
 
-@plugin.finalize
-def finalize():
-    global timer_temperature
-    enabled = cfg.setndefault('host', 'publish_temperature', 'enabled', value=True)
-    wait_time = cfg.setndefault('host', 'publish_temperature', 'timer_interval_sec', value=5)
-    timer_temperature = GenericEndlessTimerClass('host.timer.cputemp', wait_time, publish_cpu_temperature)
-    timer_temperature.__doc__ = "Endless timer for publishing CPU temperature"
-    # Note: Since timer_temperature is an instance of a class from a different module,
-    # auto-registration would register it with that module. Manually set package to this plugin module
-    plugin.register(timer_temperature, name='timer_temperature', package=plugin.loaded_as(__name__))
-    if enabled:
-        publish_cpu_temperature()
-        timer_temperature.start()
-
+def command_exists(command):
+    ret = shutil.which(command)
+    return ret is not None
 
-@plugin.atexit
-def atexit(**ignored_kwargs):
-    global timer_temperature
-    timer_temperature.cancel()
-    return timer_temperature.timer_thread
 
+@plugin.register
+def hdmi_power_down():
+    """Power down HDMI circuits to save power if no display is connected
 
-# ---------------------------------------------------------------------------
-# RPi-only stuff
-# ---------------------------------------------------------------------------
-if IS_RPI:  # noqa: C901
-
-    THROTTLE_CODES = {
-        0x1: "under-voltage detected",
-        0x2: "ARM frequency capped",
-        0x4: "currently throttled",
-        0x8: "soft temperature limit active",
-        0x10000: "under-voltage has occurred",
-        0x20000: "ARM frequency capped has occurred",
-        0x40000: "throttling has occurred",
-        0x80000: "soft temperature limit has occurred"
-    }
-
-    @plugin.register
-    def hdmi_power_down():
-        """Power down HDMI circuits to save power if no display is connected
-
-        This must be done after every reboot"""
+    This must be done after every reboot"""
+    success = False
+    commandname = "tvservice"
+    if command_exists(commandname):
         logger.info('Power down HDMI circuits')
-        ret = subprocess.run(['sudo', '/usr/bin/tvservice', '-o'],
-                             stdout=subprocess.PIPE, stderr=subprocess.STDOUT, check=False)
+        ret = subprocess.run(['sudo', commandname, '-o'],
+                            stdout=subprocess.PIPE, stderr=subprocess.STDOUT, check=False)
         if ret.returncode != 0:
             logger.error(f"{ret.stdout}")
+        else:
+            success = True
+    else:
+        logger.info('Power down HDMI not available on this system')
 
-    def filter_throttle_codes(code):
-        for error, msg in THROTTLE_CODES.items():
-            if code & error > 0:
-                yield msg
+    return success
 
-    @plugin.register
-    def get_throttled():
+
+def filter_throttle_codes(code):
+    for error, msg in THROTTLE_CODES.items():
+        if code & error > 0:
+            yield msg
+
+
+@plugin.register
+def get_throttled():
+    commandname = "vcgencmd"
+    if command_exists(commandname):
         # https://www.raspberrypi.org/documentation/computers/os.html#get_throttled
-        ret = subprocess.run(['sudo', 'vcgencmd', 'get_throttled'],
-                             stdout=subprocess.PIPE, check=False)
+        ret = subprocess.run(['sudo', commandname, 'get_throttled'],
+                            stdout=subprocess.PIPE, check=False)
         if ret.returncode != 0:
             status_string = f"Error in subprocess with code: {ret.returncode}"
             logger.error(status_string)
@@ -384,11 +356,44 @@ def get_throttled():
                 else:
                     # Decode the bit array after we have handled all the possible exceptions
                     status_string = "Warning: " + ', '.join(filter_throttle_codes(status_code))
+    else:
+        logger.info('Throttled state not available on this system')
+        status_string = "Not available"
+
+    return status_string
+
+
+# ---------------------------------------------------------------------------
+# Init
+# ---------------------------------------------------------------------------
+@plugin.initialize
+def initialize():
+    wlan_power = cfg.setndefault('host', 'wlan_power', 'disable_power_down', value=True)
+    card = cfg.setndefault('host', 'wlan_power', 'card', value='wlan0')
+    if wlan_power:
+        wlan_disable_power_down(card)
+    hdmi_off = cfg.setndefault('host', 'rpi', 'hdmi_power_down', value=False)
+    if hdmi_off:
+        hdmi_power_down()
+
+
+@plugin.finalize
+def finalize():
+    global timer_temperature
+    enabled = cfg.setndefault('host', 'publish_temperature', 'enabled', value=True)
+    wait_time = cfg.setndefault('host', 'publish_temperature', 'timer_interval_sec', value=5)
+    timer_temperature = GenericEndlessTimerClass('host.timer.cputemp', wait_time, publish_cpu_temperature)
+    timer_temperature.__doc__ = "Endless timer for publishing CPU temperature"
+    # Note: Since timer_temperature is an instance of a class from a different module,
+    # auto-registration would register it with that module. Manually set package to this plugin module
+    plugin.register(timer_temperature, name='timer_temperature', package=plugin.loaded_as(__name__))
+    if enabled:
+        publish_cpu_temperature()
+        timer_temperature.start()
 
-        return status_string
 
-    @plugin.initialize
-    def rpi_initialize():
-        hdmi_off = cfg.setndefault('host', 'rpi', 'hdmi_power_down', value=False)
-        if hdmi_off:
-            hdmi_power_down()
+@plugin.atexit
+def atexit(**ignored_kwargs):
+    global timer_temperature
+    timer_temperature.cancel()
+    return timer_temperature.timer_thread