klippy: Improve error reporting during connect

Catch exceptions during the connect phase and report them via the
gcode interface to the user.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

klippy/gcode.py

@@ -109,7 +109,7 @@ class GCodeParser:
             except:
                 logging.exception("Exception in command handler")
                 self.toolhead.force_shutdown()
-                self.respond('Error: Internal error on command:"%s"' % (cmd,))
+                self.respond_error('Internal error on command:"%s"' % (cmd,))
             # Check if machine can process next command or must stall input
             if self.busy_state is not None:
                 break
@@ -146,6 +146,11 @@ class GCodeParser:
         if self.is_fileinput:
             return
         os.write(self.fd, msg+"\n")
+    def respond_error(self, msg):
+        lines = msg.strip().split('\n')
+        for line in lines[:-1]:
+            self.respond('// %s' % (line.strip(),))
+        self.respond('!! %s' % (lines[-1].strip(),))
     # Busy handling
     def set_busy(self, busy_handler):
         self.busy_state = busy_handler
@@ -154,12 +159,12 @@ class GCodeParser:
         try:
             busy = self.busy_state.check_busy(eventtime)
         except homing.EndstopError, e:
-            self.respond("Error: %s" % (e,))
+            self.respond_error(str(e))
             busy = False
         except:
             logging.exception("Exception in busy handler")
             self.toolhead.force_shutdown()
-            self.respond('Error: Internal error in busy handler')
+            self.respond_error('Internal error in busy handler')
             busy = False
         if busy:
             self.toolhead.reset_motor_off_time(eventtime)
@@ -208,7 +213,7 @@ class GCodeParser:
     # Individual command handlers
     def cmd_default(self, params):
         if not self.is_printer_ready:
-            self.respond('Error: Printer is not ready')
+            self.respond_error(self.printer.get_state_message())
             return
         cmd = params.get('#command')
         if not cmd:
@@ -233,7 +238,7 @@ class GCodeParser:
         try:
             self.toolhead.move(self.last_position, self.speed, sloppy)
         except homing.EndstopError, e:
-            self.respond("Error: %s" % (e,))
+            self.respond_error(str(e))
             self.last_position = self.toolhead.get_position()
     def cmd_G4(self, params):
         # Dwell
@@ -244,7 +249,7 @@ class GCodeParser:
         self.toolhead.dwell(delay)
     def cmd_G20(self, params):
         # Set units to inches
-        self.respond('Error: Machine does not support G20 (inches) command')
+        self.respond_error('Machine does not support G20 (inches) command')
     def cmd_G21(self, params):
         # Set units to millimeters
         pass

klippy/klippy.py

@@ -7,6 +7,32 @@
 import sys, optparse, ConfigParser, logging, time, threading
 import gcode, toolhead, util, mcu, fan, heater, extruder, reactor, queuelogger
 
+message_startup = """
+The klippy host software is attempting to connect.  Please
+retry in a few moments.
+Printer is not ready
+"""
+
+message_restart = """
+This is an unrecoverable error.  Please correct the
+underlying issue and then manually restart the klippy host
+software.
+Printer is halted
+"""
+
+message_mcu_connect_error = """
+This is an unrecoverable error.  Please manually restart
+both the firmware and the host software.
+Error configuring printer
+"""
+
+message_shutdown = """
+This is an unrecoverable error.  Please correct the
+underlying issue and then manually restart both the
+firmware and the host software.
+Printer is shutdown
+"""
+
 class ConfigWrapper:
     def __init__(self, printer, section):
         self.printer = printer
@@ -38,6 +64,7 @@ class Printer:
         self.stats_timer = self.reactor.register_timer(self.stats)
         self.connect_timer = self.reactor.register_timer(
             self.connect, self.reactor.NOW)
+        self.state_message = message_startup
         self.debugoutput = self.dictionary = None
         self.fileconfig = None
         self.mcu = None
@@ -74,6 +101,7 @@ class Printer:
         self.gcode.build_config()
         self.mcu.build_config()
     def connect(self, eventtime):
+        try:
             self.load_config()
             if self.debugoutput is None:
                 self.reactor.update_timer(self.stats_timer, self.reactor.NOW)
@@ -82,15 +110,33 @@ class Printer:
             self.mcu.connect()
             self.build_config()
             self.gcode.set_printer_ready(True)
+            self.state_message = "Running"
+        except mcu.error, e:
+            logging.exception("MCU error during connect")
+            self.state_message = "%s%s" % (str(e), message_mcu_connect_error)
+            self.reactor.update_timer(self.stats_timer, self.reactor.NEVER)
+        except:
+            logging.exception("Unhandled exception during connect")
+            self.state_message = "Internal error during connect.%s" % (
+                message_restart)
+            self.reactor.update_timer(self.stats_timer, self.reactor.NEVER)
         self.reactor.unregister_timer(self.connect_timer)
         return self.reactor.NEVER
     def run(self):
+        try:
             self.reactor.run()
+        except:
+            logging.exception("Unhandled exception during run")
+            return
         # If gcode exits, then exit the MCU
         self.stats(time.time())
         self.mcu.disconnect()
         self.stats(time.time())
-    def note_shutdown(self):
+    def get_state_message(self):
+        return self.state_message
+    def note_shutdown(self, msg):
+        self.state_message = "Firmware shutdown: %s%s" % (
+            msg, message_shutdown)
         self.gcode.set_printer_ready(False)
 
 

klippy/mcu.py

@@ -336,7 +336,7 @@ class MCU:
         self.is_shutdown = True
         logging.info("%s: %s" % (params['#name'], params['#msg']))
         self.serial.dump_debug()
-        self._printer.note_shutdown()
+        self._printer.note_shutdown(params['#msg'])
     # Connection phase
     def connect(self):
         if not self._is_fileoutput:
@@ -421,8 +421,7 @@ class MCU:
             if not self._is_fileoutput:
                 config_params = self.serial.send_with_response(msg, 'config')
         if self._config_crc != config_params['crc']:
-            logging.error("Printer CRC does not match config")
+            raise error("Printer CRC does not match config")
-            sys.exit(1)
         logging.info("Configured")
         stepqueues = tuple(s._stepqueue for s in self._steppers)
         self._steppersync = self.ffi_lib.steppersync_alloc(