query_endstops: Add get_status() method that reports the last query state

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

docs/Command_Templates.md

@@ -175,6 +175,11 @@ The following are common printer attributes:
   available temperature sensors by their full config section names,
   e.g. `["extruder", "heater_bed", "heater_generic my_custom_heater",
   "temperature_sensor electronics_temp"]`.
+- `printer.query_endstops.last_query["<endstop>"]`: Returns True if
+  the given endstop was reported as "triggered" during the last
+  QUERY_ENDSTOP command. Note, due to the order of template expansion
+  (see above), the QUERY_STATUS command must be run prior to the macro
+  containing this reference.
 
 The above list is subject to change - if using an attribute be sure to
 review the [Config Changes document](Config_Changes.md) when upgrading

klippy/extras/query_endstops.py

@@ -8,21 +8,24 @@ class QueryEndstops:
     def __init__(self, config):
         self.printer = config.get_printer()
         self.endstops = []
+        self.last_state = {}
         gcode = self.printer.lookup_object('gcode')
         gcode.register_command("QUERY_ENDSTOPS", self.cmd_QUERY_ENDSTOPS,
                                desc=self.cmd_QUERY_ENDSTOPS_help)
         gcode.register_command("M119", self.cmd_QUERY_ENDSTOPS)
     def register_endstop(self, mcu_endstop, name):
         self.endstops.append((mcu_endstop, name))
+    def get_status(self, eventtime):
+        return {'last_query': {name: value for name, value in self.last_state}}
     cmd_QUERY_ENDSTOPS_help = "Report on the status of each endstop"
     def cmd_QUERY_ENDSTOPS(self, params):
         # Query the endstops
         print_time = self.printer.lookup_object('toolhead').get_last_move_time()
-        out = [(name, mcu_endstop.query_endstop(print_time))
-               for mcu_endstop, name in self.endstops]
+        self.last_state = [(name, mcu_endstop.query_endstop(print_time))
+                           for mcu_endstop, name in self.endstops]
         # Report results
         msg = " ".join(["%s:%s" % (name, ["open", "TRIGGERED"][not not t])
-                        for name, t in out])
+                        for name, t in self.last_state])
         gcode = self.printer.lookup_object('gcode')
         gcode.respond(msg)