power: printer power on/off control plugin

Sign-off-by: Jordan Ruthe <jordanruthe@gmail.com>

docs/installation.md

@@ -174,8 +174,9 @@ batch subscription updates together.
 
 ## Plugin Configuration
 The core plugins are configured via the primary configuration above.  Optional
-plugins each need their own configuration.  Currently the only optional plugin
+plugins each need their own configuration as outlined below.
-available is the `paneldue` plugin, which can be configured as follows:
+
+### PanelDue Plugin
 
 ```
 [moonraker_plugin paneldue]
@@ -206,4 +207,31 @@ gcode:
   { printer.moonraker.action_call_remote_method(
 		"paneldue_beep", frequency=FREQUENCY|int,
 		duration=DURATION|float) }
-```
+```
+
+### Power Control Plugin
+```
+[moonraker_plugin power]
+devices: printer, led           
+#  A comma separated list of devices you wish to control. Do not use spaces in
+#  the device's name here
+#{dev}_name: Friendly Name
+#  This is the friendly name for the device. {dev} must be swapped for the name
+#  of the device used under devices, as an example:
+#  printer_name: My Printer
+{dev}_pin: 23
+#  This option is required.
+#  The GPIO Pin number you wish to control
+#{dev}_active_low: False
+#  If you have a device that needs a low or 0 signal to be turned on, set this
+#  option to True.
+```
+
+Define the devices you wish to control under _devices_ with a comma separated
+list. For device specific configrations, swap {dev} for the name of the device
+that you listed under devices.
+
+Each device can have a Friendly Name, pin, and activehigh set. Pin is the only
+required option. For devices that should be active when the signal is 0 or low,
+set {dev}_activehigh to False, otherwise don't put the option in the
+configuration.

moonraker/plugins/power.py

@@ -0,0 +1,167 @@
+# Raspberry Pi Power Control
+#
+# Copyright (C) 2020 Jordan Ruthe <jordanruthe@gmail.com>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+
+import logging
+import os
+import time
+
+class PrinterPower:
+    def __init__(self, server):
+        self.server = server
+        self.server.register_endpoint(
+            "/printer/power/devices", "power_devices", ['GET'],
+            self._handle_list_devices)
+        self.server.register_endpoint(
+            "/printer/power/status", "power_status", ['GET'],
+            self._handle_power_request)
+        self.server.register_endpoint(
+            "/printer/power/on", "power_on", ['POST'],
+            self._handle_power_request)
+        self.server.register_endpoint(
+            "/printer/power/off", "power_off", ['POST'],
+            self._handle_power_request)
+
+        self.current_dev = None
+        self.devices = {}
+
+    async def _handle_list_devices(self, path, method, args):
+        output = {"devices": []}
+        for dev in self.devices:
+            output['devices'].append({
+                "name": self.devices[dev]["name"],
+                "id": dev
+            })
+        return output
+
+    async def _handle_power_request(self, path, method, args):
+        if len(args) == 0:
+            if path == "/printer/power/status":
+                args = self.devices
+            else:
+                return "no_devices"
+
+        result = {}
+        for dev in args:
+            if dev not in self.devices:
+                result[dev] = "device_not_found"
+                continue
+
+            GPIO.verify_pin(self.devices[dev]["pin"], self.devices[dev]["active_low"])
+            if path == "/printer/power/on":
+                GPIO.set_pin_value(self.devices[dev]["pin"], 1)
+            elif path == "/printer/power/off":
+                GPIO.set_pin_value(self.devices[dev]["pin"], 0)
+            elif path != "/printer/power/status":
+                raise self.server.error("Unsupported power request")
+
+            self.devices[dev]["status"] = GPIO.is_pin_on(self.devices[dev]["pin"])
+
+            result[dev] = self.devices[dev]["status"]
+        return result
+
+    def load_config(self, config):
+        if "devices" not in config.keys():
+            return
+
+        devices = config["devices"].split(',')
+        logging.info("Power plugin loading devices: " + str(devices))
+
+        for dev in devices:
+            dev = dev.strip()
+            if dev + "_pin" not in config.keys():
+                logging.info("Power plugin: ERR " + dev + " does not have a pin defined")
+                continue
+
+            self.devices[dev] = {
+                "name": config[dev + "_name"] if dev + "_name" in config.keys() else dev,
+                "pin": int(config[dev + "_pin"]),
+                "active_low": 1 if dev+"_active_low" in config.keys() and config[dev+"_active_low"] == "True" else 0,
+                "status": None
+            }
+
+            try:
+                logging.debug("Attempting to configure pin GPIO" + str(self.devices[dev]["pin"]))
+                GPIO.setup_pin(self.devices[dev]["pin"], self.devices[dev]["active_low"])
+                self.devices[dev]["status"] = GPIO.is_pin_on(self.devices[dev]["pin"])
+            except:
+                logging.info("Power plugin: ERR Problem configuring the output pin for device " + dev + ". Removing device")
+                self.devices.pop(dev, None)
+                continue
+
+class GPIO:
+    gpio_root = "/sys/class/gpio"
+
+    @staticmethod
+    def _set_gpio_option(gpio, option, value):
+        GPIO._write(
+            os.path.join(GPIO.gpio_root, "gpio"+str(gpio), option),
+            value
+        )
+
+    def _get_gpio_option(pin, option):
+        return GPIO._read(
+            os.path.join(GPIO.gpio_root, "gpio"+str(pin), option)
+        )
+
+    @staticmethod
+    def _write(file, data):
+        with open(file, 'w') as f:
+            f.write(str(data))
+            f.flush()
+
+    @staticmethod
+    def _read(file):
+        with open(file, 'r') as f:
+            f.seek(0)
+            return f.read().strip()
+
+    @staticmethod
+    def verify_pin(pin, active_low=1):
+        gpiopath = os.path.join(GPIO.gpio_root, "gpio"+str(pin))
+        if not os.path.exists(gpiopath):
+            logging.info("Re-intializing GPIO"+str(pin))
+            GPIO.setup_pin(pin, active_low)
+            return
+
+        if GPIO._get_gpio_option(pin, "active_low").strip() != str(active_low):
+            GPIO._set_gpio_option(pin, "active_low", active_low)
+
+        if GPIO._get_gpio_option(pin, "direction").strip() != "out":
+            GPIO._set_gpio_option(pin, "direction", "out")
+
+    @staticmethod
+    def setup_pin(pin, active_low=1):
+        pin = int(pin)
+        active_low = 1 if active_low == 1 else 0
+
+        gpiopath = os.path.join(GPIO.gpio_root, "gpio"+str(pin))
+        if not os.path.exists(gpiopath):
+            GPIO._write(
+                os.path.join(GPIO.gpio_root, "export"),
+                pin)
+            logging.info("Waiting for GPIO"+str(pin)+" to initialize")
+            while os.stat(os.path.join(GPIO.gpio_root, "gpio"+str(pin),"active_low")).st_gid == 0:
+                time.sleep(.1)
+
+        if GPIO._get_gpio_option(pin, "active_low").strip() != str(active_low):
+            GPIO._set_gpio_option(pin, "active_low", active_low)
+            
+        if GPIO._get_gpio_option(pin, "direction").strip() != "out":
+            GPIO._set_gpio_option(pin, "direction", "out")
+
+
+    @staticmethod
+    def is_pin_on(pin):
+        return "on" if int(GPIO._get_gpio_option(pin, "value")) else "off"
+
+    @staticmethod
+    def set_pin_value(pin, active):
+        value = 1 if (active == 1) else 0
+        GPIO._set_gpio_option(pin, "value", value)
+
+
+def load_plugin(server):
+    return PrinterPower(server)