implementation of an example jsonSocketServer

- jsonSocketServer for receive alarm-messages from BOSWatch.
- jsonSocketServer controlls an pibrella-bord in case of received POCSAG-RIC

serverExamples/jsonSocketServer.py

@@ -0,0 +1,148 @@
+#!/usr/bin/python
+# -*- coding: cp1252 -*-
+#
+
+"""
+jsonSocketServer
+This is a small example of an jsonSocketServer for receive alarm-messages from BOSWatch.
+The jsonSocketServer controlls an pibrella-bord in case of received POCSAG-RIC
+
+Implemented functions:
+- asynchronous service for alarm-sound
+- green LED if jsonSocketServer is running
+- green LED is blinking if Dau-Test-RIC was received
+- yellow LED is blinking if our RICs is reveived with functioncode "a"
+- red LED is blinking in case of an alarm (our RICs with functioncode "b")
+- siren will run with the pack
+- press Pibrella button to stop alarm and reset the LEDs
+
+@author: Jens Herrmann	
+
+BOSWatch: https://github.com/Schrolli91/BOSWatch
+Pibrella: https://github.com/pimoroni/pibrella
+"""
+
+# no IP for server necessary
+IP = ""
+# listen on port
+PORT = 8112
+
+
+import logging
+import logging.handlers
+
+import socket # for udp-socket
+import pibrella # for pi-board
+import json # for data
+
+
+#
+# Eventhandler for button
+# will stop the alarm and reset the LEDs
+# 
+def button_pressed(pin):
+	global siren_stopped
+	import pibrella
+	pibrella.light.off()
+	pibrella.light.green.on()
+	siren_stopped = True
+# load Eventhandler
+pibrella.button.pressed(button_pressed)
+
+#
+# Siren-control
+#
+
+# normally we have no alarm, siren-control-var is True
+siren_stopped = True
+
+# asynchronous siren:
+def siren():
+	import time
+	if siren_stopped == True:
+		pibrella.buzzer.stop()
+		return True
+	for x in xrange(-30,30,2):
+		pibrella.buzzer.note(x)
+		time.sleep(0.01)
+	for x in reversed(xrange(-30,30,2)):
+		pibrella.buzzer.note(x)
+		time.sleep(0.01)
+# start asynchronous siren
+pibrella.async_start('siren',siren)
+
+
+#
+# Main Program
+#
+try: 
+	# Logging
+	myLogger = logging.getLogger()
+	myLogger.setLevel(logging.DEBUG)
+	formatter = logging.Formatter('%(asctime)s [%(levelname)-8s] %(message)s', '%d.%m.%Y %H:%M:%S')
+	ch = logging.StreamHandler()
+	ch.setLevel(logging.DEBUG) 
+	ch.setFormatter(formatter)
+	myLogger.addHandler(ch)		
+
+	# Start TCP socket:
+	logging.debug("Start jsonSocketServer")
+	sock = socket.socket()
+	sock.bind((IP,PORT))
+	sock.listen(2)
+	logging.info("jsonSocketServer runs")
+	pibrella.light.green.on() 
+
+	# our Alarm-RICs:
+	ric_alarm = [12345677, 12345676, 12345675]
+
+	while True:
+		# accept connections from outside
+		(clientsocket, address) = sock.accept()
+		logging.debug("connected client: %s", address)
+
+		# receive message as json string
+		json_string = clientsocket.recv( 4096 ) # buffer size is 4096 bytes
+		try:
+			# parse json
+			parsed_json = json.loads(json_string)
+			logging.debug("parsed message: %s", parsed_json)
+		except ValueError:
+			# parsing error is foolish, but we don't have to exit
+			logging.warning("No JSON object could be decoded: %s", json_string)
+			pass
+		else:
+			# DAU-Test-RIC received
+			if parsed_json['ric'] == "1234567":
+				logging.debug("POCSAG is alive")
+				pibrella.light.green.blink(1, 1)
+			
+			elif int(parsed_json['ric']) in ric_alarm:
+				logging.debug("We have do to something")
+				if parsed_json['functionChar'] == "a":
+					logging.info("-> Probealarm: %", parsed_json['ric'])
+					pibrella.light.yellow.blink(1, 1)
+				elif parsed_json['functionChar'] == "b":
+					logging.info("-> Alarm: %", parsed_json['ric'])
+					pibrella.light.red.blink(1, 1)
+					# change variable to False to start the siren
+					siren_stopped = False
+				
+except KeyboardInterrupt:
+	logging.warning("Keyboard Interrupt")	
+except:
+	logging.exception("unknown error")
+finally:
+	try:
+		logging.debug("socketServer shuting down")
+		sock.close()
+		logging.debug("socket closed") 
+		logging.debug("exiting socketServer")		
+	except:
+		logging.warning("failed in clean-up routine")	
+	finally:	
+		logging.debug("close Logging")	
+		logging.info("socketServer exit()")
+		logging.shutdown()
+		ch.close()
+		exit(0)