Merge deltas from the GTFS-R feed into the estimations

gtfs_client.py

@@ -3,6 +3,7 @@ import refresh_feed
 from arrival_times import ArrivalTime
 import datetime
 import gtfs_kit as gk
+import json
 import os
 import pandas as pd
 import queue
@@ -192,22 +193,46 @@ class GTFSClient():
 
         return joined_data 
 
-    def _time_to_seconds(self, s: str) -> int:
+    def __time_to_seconds(self, s: str) -> int:
         sx = s.split(":")
         if len(sx) != 3: 
             print("Malformed timestamp:", s)
             return 0
         return int(sx[0]) * 3600 + int(sx[1]) * 60 + int (sx[2])
 
-    def _due_in_seconds(self, time_str: str) -> int:
+    def __due_in_seconds(self, time_str: str) -> int:
         """
         Returns the number of seconds in the future that the time_str (format hh:mm:ss) is
         """
         now = datetime.datetime.now().strftime("%H:%M:%S")
-        tnow = self._time_to_seconds(now)
-        tstop = self._time_to_seconds(time_str)
+        tnow = self.__time_to_seconds(now)
+        tstop = self.__time_to_seconds(time_str)
         return tstop - tnow
 
+    def __poll_gtfsr_deltas(self) -> list[map, set]:
+        deltas_json = json.load(open("example.json"))
+
+        deltas = {}
+        canceled_trips = set()
+
+        for e in deltas_json.get("Entity"):
+            is_deleted = e.get("IsDeleted") or False
+            try:
+                trip_id = e.get("TripUpdate").get("Trip").get("TripId")
+                if e.get("TripUpdate").get("Trip").get("ScheduleRelationship") == "Scheduled":
+                    for u in e.get("TripUpdate").get("StopTimeUpdate"): 
+                        delay = u.get("Arrival", u.get("Departure", {})).get("Delay", 0)
+                        deltas_for_trip = (deltas.get(trip_id) or {})
+                        deltas_for_trip[u.get("StopId")] = delay
+                        deltas[trip_id] = deltas_for_trip
+                else:
+                    canceled_trips.add(trip_id)
+            except Exception as x:
+                print("Error parsing GTFS-R entry:", str(e))
+                raise(x)
+            
+        return deltas, canceled_trips
+
 
     def get_next_n_buses(self, num_entries: int) -> pd.core.frame.DataFrame:
         """
@@ -230,18 +255,29 @@ class GTFSClient():
         """
         Create and enqueue the refreshed stop data
         """
-        
-        arrivals = []
+        # Retrieve the GTFS-R deltas
+        deltas, canceled_trips = self.__poll_gtfsr_deltas()
 
-        buses = self.get_next_n_buses(5)
+        # 
+        arrivals = []
+        # take more entries than we need in case there are cancelations 
+        buses = self.get_next_n_buses(10) 
         
         for index, bus in buses.iterrows():
-            arrival = ArrivalTime(stop_id = bus["stop_id"], 
-                                  route_id = bus["route_short_name"],
-                                  destination= bus["route_long_name"].split(" - ")[1].strip(),
-                                  due_in_seconds = self._due_in_seconds(bus["arrival_time"])
-            )
-            arrivals.append(arrival)
+            if not bus["trip_id"] in canceled_trips:
+                delta = deltas.get(bus["trip_id"], {}).get(bus["stop_id"], 0)
+                if delta != 0:
+                    print("Delta for route {} stop {} is {}".format(bus["route_short_name"], bus["stop_id"], delta))
+
+                arrival = ArrivalTime(stop_id = bus["stop_id"], 
+                                    route_id = bus["route_short_name"],
+                                    destination= bus["route_long_name"].split(" - ")[1].strip(),
+                                    due_in_seconds = self.__due_in_seconds(bus["arrival_time"]) + delta
+                )
+                arrivals.append(arrival)
+
+        # Select the first 5 of what remains
+        arrivals = arrivals[0:5]
 
         if self._update_queue:
             self._update_queue.put(arrivals)
@@ -267,4 +303,4 @@ def every(delay, task) -> None:
 if __name__ == "__main__":
     c = GTFSClient('https://www.transportforireland.ie/transitData/google_transit_combined.zip', 
                    ['College Drive, stop 2410', 'Priory Walk, stop 1114'], None, None)
-    print(c.refresh())
+    print(c.refresh())