78 lines
2.3 KiB
Python
78 lines
2.3 KiB
Python
import paho.mqtt.client as mqtt
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import time
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import umsgpack
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class Commander:
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currentVote = None
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# Stores voters that connect to maintain a majority.
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# Voters who do not vote in latest round are removed.
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connectedVoters = {}
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votes = []
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taking_votes = False
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def __init__(self, timeout = 60):
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'''
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Initial/default waiting time is 1 minute for votes to come in.
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'''
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self.timeout = timeout
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self.client = mqtt.Client()
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self.client.connect('172.16.13.128')
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# Commander needs a will message too, for the decentralised version, so the
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# voters know to pick a new commander.
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def make_decision(self):
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# Could change this to be a strategy, for different implementations of making
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# a decision on the votes.
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votes = self._votes
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dif_votes = {}
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for vote in votes:
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# Get the average/max, etc.
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if str(vote) in dif_votes:
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dif_votes[str(vote)] = dif_votes[str(vote)] + 1
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else:
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dif_votes[str(vote)] = 1
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max_vote = None
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max_vote_num = 0
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for vote in dif_votes.keys():
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if dif_votes[vote] > max_vote_num:
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max_vote = vote
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max_vote_num = dif_votes[vote]
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return max_vote
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def get_votes():
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message = {"type": "voteRequest"}
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message_packed = umsgpack.packb(message)
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# Publish a message that votes are needed.
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ms.client.publish("swarm1/voters", message_packed, qos)
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time.sleep(self.timeout)
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self.make_decision()
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def add_subscription(self, topic, callback=None, qos=0):
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ms.client.subscribe(topic)
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if callback is not None:
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ms.client.message_callback_add(topic, callback)
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def on_message(self, client, userdata, message):
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messageDict = umsgpack.unpackb()
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if "type" in messageDict.keys:
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if messageDict["type"] == "connect":
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# Voter just connected/reconnnected.
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elif messageDict["type"] == "vote":
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# Voter is sending in their vote.
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if messageDict[""]
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else:
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# Not a message we should be using.
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NotImplementedError
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def on_connect(client, userdata, flags, rc):
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self.client.subscribe("swarm1/commander") |