new function: install shell command extension by Arksine

docs/Shell Command Extension.md

@@ -0,0 +1,46 @@
+# Shell Command Extension
+
+### Creator of this extension is [Arksine](https://github.com/Arksine).
+
+This is a brief explanation of how to use the shell command extension for Klipper, which you can install with KIAUH.
+
+After installing the extension you can execute linux commands or even scripts from within Klipper with custom commands defined in your printer.cfg.
+
+#### How to configure a shell command:
+
+```shell
+# Runs a linux command or script from within klipper.  Note that sudo commands
+# that require password authentication are disallowed. All executable scripts
+# should include a shebang.
+# [shell_command my_shell_cmd]
+#command:
+#  The linux shell command/script to be executed.  This parameter must be
+#  provided
+#timeout: 2.
+#  The timeout in seconds until the command is forcably terminated.  Default
+#  is 2 seconds.
+#verbose: True
+#  If enabled, the command's output will be forwarded to the terminal.  Its
+#  recommended to set this to false for commands that my run in quick
+#  succession.  Default is True.
+```
+
+Once you have set up a shell command with the given parameters from above in your printer.cfg you can run the command as follows:
+`RUN_SHELL_COMMAND CMD=name`
+
+Example:
+
+```
+[shell_command hello_world]
+command: echo hello world
+timeout: 2.
+verbose: True
+```
+
+Execute with:
+`RUN_SHELL_COMMAND CMD=hello_world`
+
+## Warning
+
+This extension may have a high potential for abuse if not used carefully! Also, depending on the command you execute, high system loads may occur and can cause system instabilities.
+Use this extension at your own risk and only if you know what you are doing!

resources/shell_command.py

@@ -0,0 +1,83 @@
+# Run a shell command via gcode
+#
+# Copyright (C) 2019  Eric Callahan <arksine.code@gmail.com>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import os
+import shlex
+import subprocess
+import logging
+
+class ShellCommand:
+    def __init__(self, config):
+        self.name = config.get_name().split()[-1]
+        self.printer = config.get_printer()
+        self.gcode = self.printer.lookup_object('gcode')
+        cmd = config.get('command')
+        cmd = os.path.expanduser(cmd)
+        self.command = shlex.split(cmd)
+        self.timeout = config.getfloat('timeout', 2., above=0.)
+        self.verbose = config.getboolean('verbose', True)
+        self.proc_fd = None
+        self.partial_output = ""
+        self.gcode.register_mux_command(
+            "RUN_SHELL_COMMAND", "CMD", self.name,
+            self.cmd_RUN_SHELL_COMMAND,
+            desc=self.cmd_RUN_SHELL_COMMAND_help)
+
+    def _process_output(self, eventime):
+        if self.proc_fd is None:
+            return
+        try:
+            data = os.read(self.proc_fd, 4096)
+        except Exception:
+            pass
+        data = self.partial_output + data
+        if '\n' not in data:
+            self.partial_output = data
+            return
+        elif data[-1] != '\n':
+            split = data.rfind('\n') + 1
+            self.partial_output = data[split:]
+            data = data[:split]
+        self.gcode.respond_info(data)
+
+    cmd_RUN_SHELL_COMMAND_help = "Run a linux shell command"
+    def cmd_RUN_SHELL_COMMAND(self, params):
+        reactor = self.printer.get_reactor()
+        try:
+            proc = subprocess.Popen(
+                self.command, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+        except Exception:
+            logging.exception(
+                "shell_command: Command {%s} failed" % (self.name))
+            raise self.gcode.error("Error running command {%s}" % (self.name))
+        if self.verbose:
+            self.proc_fd = proc.stdout.fileno()
+            self.gcode.respond_info("Running Command {%s}...:" % (self.name))
+            hdl = reactor.register_fd(self.proc_fd, self._process_output)
+        eventtime = reactor.monotonic()
+        endtime = eventtime + self.timeout
+        complete = False
+        while eventtime < endtime:
+            eventtime = reactor.pause(eventtime + .05)
+            if proc.poll() is not None:
+                complete = True
+                break
+        if not complete:
+            proc.terminate()
+        if self.verbose:
+            if self.partial_output:
+                self.gcode.respond_info(self.partial_output)
+                self.partial_output = ""
+            if complete:
+                msg = "Command {%s} finished\n" % (self.name)
+            else:
+                msg = "Command {%s} timed out" % (self.name)
+            self.gcode.respond_info(msg)
+            reactor.unregister_fd(hdl)
+            self.proc_fd = None
+
+
+def load_config_prefix(config):
+    return ShellCommand(config)

scripts/functions.sh

@@ -331,3 +331,76 @@ remove_branding(){
     esac
   done
 }
+
+install_extension_shell_command(){
+  echo
+  top_border
+  echo -e "| You are about to install the shell command extension. |"
+  echo -e "| Please make sure to read the instructions before you  |"
+  echo -e "| continue and remember that there are potential risks! |"
+  bottom_border
+  while true; do
+    read -p "${cyan}###### Do you want to continue? (Y/n):${default} " yn
+    case "$yn" in
+      Y|y|Yes|yes|"")
+        if [ -d $KLIPPER_DIR/klippy/extras ] && [ ! -f $KLIPPER_DIR/klippy/extras/shell_command.py ] ; then
+          status_msg "Installing shell command extension ..."
+          stop_klipper
+          cp ${HOME}/kiauh/resources/shell_command.py $KLIPPER_DIR/klippy/extras
+          status_msg "Creating example macro ..."
+          create_shell_command_example
+          ok_msg "Example macro created!"
+          ok_msg "Shell command extension installed!"
+          restart_klipper
+        else
+          if [ ! -d $KLIPPER_DIR/klippy/extras ]; then
+            ERROR_MSG="Folder ~/klipper/klippy/extras not found!"
+          fi
+          if [ -f $KLIPPER_DIR/klippy/extras/shell_command.py ]; then
+            ERROR_MSG="Extension already installed!"
+          fi
+        fi
+        break;;
+      N|n|No|no)
+        break;;
+    esac
+  done
+}
+
+create_shell_command_example(){
+  unset SC_ENTRY
+  unset write_entries
+  #check for a SAVE_CONFIG entry
+  SC="#*# <---------------------- SAVE_CONFIG ---------------------->"
+  if [[ $(grep "$SC" ${HOME}/printer.cfg) ]]; then
+    SC_LINE=$(grep -n "$SC" $PRINTER_CFG | cut -d ":" -f1)
+    PRE_SC_LINE=$(expr $SC_LINE - 1)
+    SC_ENTRY="true"
+  else
+    SC_ENTRY="false"
+  fi
+  #example shell command
+  write_entries+=("[shell_command hello_world]\ncommand: echo hello world\ntimeout: 2.\nverbose: True")
+  #example macro
+  write_entries+=("[gcode_macro HELLO_WORLD]\ngcode:\n    RUN_SHELL_COMMAND CMD=hello_world")
+  if [ "${#write_entries[@]}" != "0" ]; then
+    write_entries+=("\\\n############################\n##### CREATED BY KIAUH #####\n############################")
+    write_entries=("############################\n" "${write_entries[@]}")
+  fi
+  #execute writing
+  status_msg "Writing to printer.cfg ..."
+  if [ "$SC_ENTRY" = "true" ]; then
+    PRE_SC_LINE="$(expr $SC_LINE - 1)a"
+    for entry in "${write_entries[@]}"
+    do
+      sed -i "$PRE_SC_LINE $entry" $PRINTER_CFG
+    done
+  fi
+  if [ "$SC_ENTRY" = "false" ]; then
+    LINE_COUNT="$(wc -l < $PRINTER_CFG)a"
+    for entry in "${write_entries[@]}"
+    do
+      sed -i "$LINE_COUNT $entry" $PRINTER_CFG
+    done
+  fi
+}