trackdirect2/server/trackdirect/websocket/queries/MostRecentPacketsQuery.py

60 lines
2.4 KiB
Python

import datetime, time, calendar
from trackdirect.repositories.PacketRepository import PacketRepository
from trackdirect.websocket.queries.MissingPacketsQuery import MissingPacketsQuery
class MostRecentPacketsQuery() :
"""This query class returnes the latest packet for moving stations and the latest packet for every uniqe position for stationary stations.
Note:
If no packet are found we will simulate them
"""
def __init__(self, state, db) :
"""The __init__ method.
Args:
state (WebsocketConnectionState): The current state for a websocket connection
db (psycopg2.Connection): Database connection
"""
self.state = state
self.db = db
self.packetRepository = PacketRepository(db)
self.simulateEmptyStation = False
def enableSimulateEmptyStation(self) :
"""Enable simulation even if we have no packet from station at all
"""
self.simulateEmptyStation = True
def getPackets(self, stationIds) :
"""Fetch the most recent packets for the specified stations.
Returns the latest packet for moving stations and the latest packet for every uniqe position for stationary stations.
Args:
stationIds (array): An array of all stations we want packets for
Returns:
array
"""
if (self.state.latestTimeTravelRequest is not None) :
timestamp = int(self.state.latestTimeTravelRequest) - (int(self.state.latestMinutesRequest)*60)
packets = self.packetRepository.getMostRecentConfirmedObjectListByStationIdListAndTimeInterval(stationIds, timestamp, self.state.latestTimeTravelRequest)
else :
timestamp = int(time.time()) - (int(self.state.latestMinutesRequest)*60)
packets = self.packetRepository.getMostRecentConfirmedObjectListByStationIdList(stationIds, timestamp)
if (len(packets) < len(stationIds)) :
# If we have no recent markers we just send the latest that we have
query = MissingPacketsQuery(self.state, self.db)
if (self.simulateEmptyStation) :
query.enableSimulateEmptyStation()
foundMissingPackets = query.getMissingPackets(stationIds, packets)
if (foundMissingPackets) :
foundMissingPackets.extend(packets)
packets = foundMissingPackets
return packets