Support for arbitrary power devices via shell commands

docs/configuration.md

@@ -1460,6 +1460,49 @@ location: 1-1
 port: 2
 ```
 
+#### Arbitrary devices via Shell commands
+
+Control any device as long as you can come up with a way to control it with a shell command.
+
+The most practical way of doing it will likely be with a short Python script, although it doesn't have to be.
+
+```ini {title="Moonraker Config Specification"}
+# moonraker.conf
+
+on_cmd:
+#   Command to be ran to switch the device on. This parameter must be provided.
+off_cmd:
+#   Command to be ran to switch the device off. This parameter must be provided.
+timeout:
+#   Number of seconds after which the subprocess spawned by the command will be 
+#   forcefully terminated. It should not need to be increased in most cases. Default is 1 second.
+```
+
+/// Warning
+These commands will not recognize the tilde (`~`) shorthand for your home directory, and as such, you must always use full paths when referring to files.
+
+`python3 /home/<user>/printer_data/psuctrl.py on` will work
+
+`python3 ~/printer_data/psuctrl.py on` will not.
+///
+
+
+Example:
+
+```ini {title="Moonraker Config Example"}
+# moonraker.conf
+
+#   This assumes the presence of a Python script in the path /home/nyan/printer_data/psuctrl.py,
+#   that recieves an 'on' or 'off' argument and controls the power supply accordingly.
+#   (eg. by sending a command via serial to an Arduino, which in turn controls the 
+#   PSU directly or via a relay)
+
+[power atx_psu]
+type: shell_cmd
+on_cmd: python3 /home/nyan/printer_data/psuctrl.py on
+off_cmd: python3 /home/nyan/printer_data/psuctrl.py off
+```
+
 #### Generic HTTP Devices
 
 Support for configurable HTTP switches.  This device type may be used when

moonraker/components/power.py

@@ -60,7 +60,8 @@ def __init__(self, config: ConfigHelper) -> None:
             "smartthings": SmartThings,
             "hue": HueDevice,
             "http": GenericHTTP,
-            "uhubctl": UHubCtl
+            "uhubctl": UHubCtl,
+            "shell_cmd": ShellCmd
         }
 
         for section in prefix_sections:
@@ -1585,6 +1586,32 @@ async def _run_uhubctl(self, action: str) -> Dict[str, Any]:
             f"port {self.port}, "
         )
 
+class ShellCmd(PowerDevice):
+    def __init__(self,
+                 config: ConfigHelper,
+                 initial_val: Optional[int] = None
+                 ) -> None:
+        super().__init__(config)
+        self.scmd: ShellCommand = self.server.load_component(config, "shell_command")
+        self.on_cmd = config.get('on_cmd')
+        self.off_cmd = config.get('off_cmd')
+        self.timeout = config.getfloat('timeout', 1.0)
+
+    async def init_state(self) -> None:
+        if self.initial_state is None:
+            self.set_power("off")
+        else:
+            self.set_power("on" if self.initial_state else "off")
+
+    def refresh_status(self) -> None:
+        pass
+
+    def set_power(self, state) -> None:
+        if state == "on":
+            self.scmd.exec_cmd(cmd=self.on_cmd, timeout=self.timeout)
+        else:
+            self.scmd.exec_cmd(cmd=self.off_cmd, timeout=self.timeout)
+        self.state = state
 
 # The power component has multiple configuration sections
 def load_component(config: ConfigHelper) -> PrinterPower: