small refactorings;

added comments;

components/i_feed/traffic_light.py

@@ -7,7 +7,7 @@ from circuitbreaker import circuit
 
 # Default switching time in seconds
 from shared import TrafficLightColor
-from shared.TrafficLightColor import Color
+from shared.TrafficLightColor import TrafficLightColor
 from shared.message_broker_wrapper import MBWrapper
 
 SWITCHING_TIME = 120
@@ -23,11 +23,11 @@ class TrafficLight:
     # timestamp of last switch
     last_switch: datetime
     # currently lit color
-    current_color: Color
+    current_color: TrafficLightColor
     # marks if traffic light started
     running: bool = False
     # stores starting color
-    _starting_color: Color
+    _starting_color: TrafficLightColor
     # stores runner thread
     _t: threading.Thread
 
@@ -37,7 +37,7 @@ class TrafficLight:
     def __init__(self,
                  tlid: str,
                  switching_time: int = SWITCHING_TIME,
-                 starting_color: Color = Color.RED):
+                 starting_color: TrafficLightColor = TrafficLightColor.RED):
         self.tlid = tlid
         self.switching_time = switching_time
         self._starting_color = starting_color
@@ -49,12 +49,12 @@ class TrafficLight:
         self.running = True
 
         def switcher():
-            num_colors = len(TrafficLightColor.Color)
+            num_colors = len(TrafficLightColor)
             # set current color to the one before starting color, because switch immediately happens in loop
             # therefore it sleeps on the end of the loop and first status is immediately sent to msg broker
-            self.current_color = Color((self._starting_color.value - 1) % num_colors)
+            self.current_color = TrafficLightColor((self._starting_color.value - 1) % num_colors)
             while self.running:
-                self.current_color = Color((self.current_color.value + 1) % num_colors)
+                self.current_color = TrafficLightColor((self.current_color.value + 1) % num_colors)
                 self.last_switch = datetime.now()
                 self.send_status_update()
                 time.sleep(self.switching_time / SCALING)

components/orchestration/orchestrator.py

@@ -1,20 +1,25 @@
 import pickle
 import sys
 from random import randrange
+from typing import List, Dict
 
 from shared import daf
-from shared.TrafficLightColor import Color
+from shared.TrafficLightColor import TrafficLightColor
 from shared.message_broker_wrapper import MBWrapper
 
+# necessary to unpickle daf object
 sys.modules['daf'] = daf
 
 
 class Orchestrator:
-    vins = []
-    tls = {}
+    # vehicle ids
+    vins: List[str] = []
+    # traffic lights {tlid: {color: color, switching_time: in_seconds}}
+    tls: Dict[str, Dict] = {}
 
-    _daf_mbs = {}
-    _velocity_mbs = {}
+    # cache all active incoming daf connections
+    _daf_mbs: Dict[str, MBWrapper] = {}
+    _velocity_mbs: Dict[str, MBWrapper] = {}
 
     def __init__(self):
         # TODO fetch available car VINs from Entity Ident
@@ -24,12 +29,13 @@ class Orchestrator:
         print('vins', self.vins)
 
         # TODO fetch available TLs from Entity Ident
-        self.tls['traffic-light-1'] = {'color': Color.RED, 'switching_time': 120}
-        self.tls['traffic-light-2'] = {'color': Color.GREEN, 'switching_time': 240}
-        self.tls['traffic-light-3'] = {'color': Color.RED, 'switching_time': 360}
+        self.tls['traffic-light-1'] = {'color': TrafficLightColor.RED, 'switching_time': 120}
+        self.tls['traffic-light-2'] = {'color': TrafficLightColor.GREEN, 'switching_time': 240}
+        self.tls['traffic-light-3'] = {'color': TrafficLightColor.RED, 'switching_time': 360}
         print('tls', self.tls)
 
     def setup_msg_queues(self):
+        # spawn the vehicle related message broker channels
         for vin in self.vins:
             daf_channel = MBWrapper(exchange_name='vehicle_daf_{}'.format(vin), callback=self.handle_daf_receive)
             daf_channel.setup_receiver()
@@ -39,20 +45,37 @@ class Orchestrator:
             velocity_channel.setup_sender()
             self._velocity_mbs[vin] = velocity_channel
 
+        # spawn the traffic light related mb channels
         for tl in self.tls:
             tl_channel = MBWrapper(exchange_name='traffic_light_state_{}'.format(tl), callback=self.handle_tl_state_receive)
             tl_channel.setup_receiver()
 
-    def handle_daf_receive(self, msg):
-        received_daf_object = pickle.loads(msg)
+    def handle_daf_receive(self, pickle_binary):
+        """
+        Gets the daf object's pickle binary dump.
+        Unpickle, calculate new target velocity based on daf and current tl data and
+        respond new target velicity for this vehicle.
+
+        :param pickle_binary: daf object pickle binary dump
+        """
+        received_daf_object = pickle.loads(pickle_binary)
         print(received_daf_object)
 
         # TODO use the data from the traffic lights (self.tls)
         #  to transmit a new target velocity for this vehicle to achieve a green wave
         response_channel = self._velocity_mbs[received_daf_object.vehicle_identification_number]
-        response_channel.send(randrange(0, 130))
+        response_channel.send(str(randrange(0, 130)).encode())
 
     def handle_tl_state_receive(self, msg):
+        """
+        Gets a dict full of traffic light state information:
+        {
+            'tlid': str,
+            'color': TrafficLightColor,
+            'last_switch': datetime
+        }
+        Updates internal information about available TLs
+        """
         tl_state = pickle.loads(msg)
         self.tls[tl_state['tlid']]['color'] = tl_state['color']
         print(tl_state)

components/shared/TrafficLightColor.py

@@ -1,6 +1,6 @@
 from enum import Enum
 
 
-class Color(Enum):
+class TrafficLightColor(Enum):
     GREEN = 0
     RED = 1