Moved to procedural style, using Events to sync

ksp_client.py

 import krpc
 import zmq
 import argparse
+from threading import Lock, Event
 
 
-class ModelRocket:
-    socket = None
-    realRocket = None 
+def main():
+    parser = argparse.ArgumentParser(description='')
+    parser.add_argument('addr', type=str, default="localhost:5556", nargs="?")
+    args = parser.parse_args()
+    host = "*"
+    port = "5556"
     topic = "events"
-    states = { -1:"abort", 0:"pre_launch",1:"liftoff", 2:"stage_1_separation", 3:"stage_2_separation"}
-    stage_map = {0:0,1:1,2:2,3:3}
-
-    def send(self,stage):
-        self.socket.send("%d %d" % (self.topic, self.stage_map[stage]))
-
-    def __init__(self,addr="localhost:5556"):
-        context = zmq.Context()
-        self.socket = context.socket(zmq.PUB)
-        self.socket.bind("tcp://%s" % addr)
+    states = {-1: "abort",
+              0: "pre_launch",
+              1: "liftoff",
+              2: "stage_1_separation",
+              3: "stage_2_separation"}
+    stage_map = dict([(i,i) for i in range(10)])
 
+    context = zmq.Context()
+    socket = context.socket(zmq.PUB)
+    socket.bind(f"tcp://{host}:{port}")
 
+    conn = krpc.connect()
 
+    running = Event()
+    stopping = Event()
 
-if __name__ == "__main__":
-    parser = argparse.ArgumentParser(description='')
-    parser.add_argument('addr', type=str, default="localhost:5556", nargs="?")
-    args = parser.parse_args()
+    def unlock(scene):
+        print(f"In GameScene {scene.name}")
+        if (scene == conn.krpc.GameScene.flight):
+            running.set()
+            stopping.clear()
+        else:
+            running.clear()
+            stopping.set()
 
-    conn = krpc.connect()
-    vessel = conn.space_center.active_vessel
-    control = vessel.control
-    rocket = ModelRocket(args.addr)
+    def stage_changed(new_stage):
+        try:
+            socket.send_string(f"{topic} {stage_map[new_stage]}")
+            print(f"Sending event {topic} {new_stage}")
+        except Exception as e:
+            pass
 
+    scene = conn.add_stream(getattr, conn.krpc, 'current_game_scene')
+    scene.add_callback(unlock)
+    scene.start()
 
+    while True:
+        running.wait()
+        running.clear()
+        vessel = conn.space_center.active_vessel
+        control = vessel.control
+        stage = conn.add_stream(getattr, control, 'current_stage', scene)
 
-    stage = conn.add_stream(getattr, control, 'current_stage')
-    stage.add_callback(rocket.send)
+        stage.add_callback(stage_changed)
+        stage.start()
 
-    def activate_callback(scene):
-        if(scene == conn.krpc.GameScene.flight):
-            stage.start()
-        else:
-            stage.wait()
+        stopping.wait()
+        stopping.clear()
+        print("Removing callback...")
+        stage.remove_callback(stage_changed)
+        stage.remove()
 
-    scene = conn.add_stream(getattr, conn.krpc, 'current_game_scene')
-    scene.add_callback(activate_callback)
 
-    while 42:
-        pass
+if __name__ == "__main__":
+    main()