class IoTInterface():
def __init__(self, componentID, mqttProvider):
self.componentID = componentID
self.mqtt = mqttProvider
self.em = EventsManager()
#subscribe to external/MQTT events to send in
self.mqtt.subscribe("roll-call/who-there", self.announce)
#receive commands addressed to this component
topic = "%s/command" % self.componentID
self.mqtt.subscribe(topic, self.processIncomingMessage)
#subscribe to internal updates to send out
topic = "%s/update" % self.componentID
self.em.subscribe(topic, self.processOutgoingMessage)
#subscribe to internal info to send out
topic = "%s/info" % self.componentID
self.em.subscribe(topic, self.processOutgoingMessage)
#announce yourself
msg = {"name": self.componentID}
self.mqtt.publish("roll-call/hello", msg)
#tell device to send its info
self.em.publish("%s/info-request" % self.componentID, {})
def destroy(self):
#unsubscribe before I get destroyed.
self.em.unsubscribe(self.processOutgoingMessage)
msg = {"name": self.componentID}
self.mqtt.publish("roll-call/goodbye", msg)
self.mqtt.unsubscribe(self.announce)
self.mqtt.unsubscribe(self.processIncomingMessage)
def announce(self, message):
msg = {"name": self.componentID}
self.mqtt.publish("roll-call/response", msg)
self.em.publish("%s/info-request" % self.componentID, {})
def processOutgoingMessage(self, message):
topic = message.pop(
"topic") #Separate the message and topic to format for MQTT server
self.mqtt.publish(topic, message)
def processIncomingMessage(self, message):
topic = message.pop("topic")
self.em.publish(topic, message)
#acknowledge
topic = "%s/response" % message["topic"]
msg = {"response": "ack"}
self.mqtt.publish(topic, msg)
class RhizoDevice():
def __init__(self, port):
print("Device: Initializing myself as a new device on port %s..." %
port)
self.port = port
self.em = EventsManager()
self.components = {} #Dict componentID:component
self.abort = False
self.deviceMessageQueue = []
self.serialConnection = SerialConnection(port, self.addToMessageQueue)
self.processMessageQueue()
self.sendCommand({
"command": "devices",
"params": None
}) #request info about what components are on the device
self.sendCommand({
"command": "interval",
"params": 2
}) #sets the data-sending rate to 1 second
print("Device: Done Initializing.")
def destroy(self):
for componentID in self.components:
self.em.unsubscribe(self.sendCommand)
self.em.publish("component-removed", {"componentID": componentID})
self.serialConnection.closeConnection()
self.serialConnection = False
self.abort = True
def addComponent(self, component_name):
componentID = "%s/%s" % (self.port, component_name)
if not componentID in self.components:
self.components[componentID] = Component(componentID)
self.em.publish("component-added", {"componentID": componentID})
self.em.subscribe("%s/command" % componentID, self.sendCommand)
self.sendCommand({
"command": "%s: info" % component_name,
"params": None
}) #request info about this component
def updateComponents(self, component_name, key, value):
componentID = "%s/%s" % (self.port, component_name)
if componentID in self.components:
self.components[componentID].updateInfo(key, value)
else:
self.addComponent(component_name)
#messaging related methods
def sendCommand(self, message):
command = message["command"]
params = message["params"]
try:
if params is not None:
msg = "%s %s" % (command, params)
self.serialConnection.writeMessage(msg)
else:
msg = command
self.serialConnection.writeMessage(msg)
except:
print("Device: Error sending command over serial connection.")
# collect messages from the SerialConnection
def addToMessageQueue(self, message):
self.deviceMessageQueue.append(message)
# process incoming serial message queue
def _processMessageQueue(self):
while True:
if not self.abort:
if len(self.deviceMessageQueue) > 0:
msg = self.deviceMessageQueue.pop(0)
msg_array = msg.decode('utf-8').split("|")[0].split(
" "
) # Ugly, but this is just how the messages seem to be formatted: "c:v 492|69100"
cmd = msg_array.pop(0).split(":")
#Decide what kind of message it was-- either meta:devices [components], or componentId:info_type [value]
if cmd[0] == "meta":
if cmd[1] == "devices":
for component in msg_array:
self.addComponent(component)
else:
if cmd[0] == "nack":
print("Device not acknowledging messages")
pass
if len(cmd) > 1:
if cmd[1] == "nack" or cmd[1] == "ack":
pass
else:
comp = cmd[0]
key = cmd[1]
value = msg_array
if key == "v":
key = "state"
self.updateComponents(comp, key, value)
else:
pass
else:
break
def processMessageQueue(self):
t = threading.Thread(target=self._processMessageQueue)
t.start()