Further cleanup

src/camera/camera/roscamera.py

@@ -1,5 +1,3 @@
-from pathlib import Path
-
 import cv2  # OpenCV library
 import rclpy  # Python Client Library for ROS 2
 from cv_bridge import CvBridge  # Package to convert between ROS and OpenCV Images
@@ -8,30 +6,30 @@
 from sensor_msgs.msg import CompressedImage  # Image is the message type
 from std_msgs.msg import String
 
-"""
-Function returns a list of working camera IDs to capture every camera connected to the robot
-"""
-
 
 def getCameras() -> list[int]:
-    nonWorkingPorts = 0
-    devPort = 0
-    workingPorts = []
+    """
+    Function returns a list of working camera IDs to capture every camera connected to the robot
+    """
 
-    while nonWorkingPorts < 6:
-        camera = cv2.VideoCapture(devPort)
+    non_working_ports = 0
+    dev_port = 0
+    working_ports = []
+
+    while non_working_ports < 6:
+        camera = cv2.VideoCapture(dev_port)
         if not camera.isOpened():
-            nonWorkingPorts += 1
+            non_working_ports += 1
         else:
-            isReading, img = camera.read()
+            is_reading, img = camera.read()
             _ = camera.get(3)
             _ = camera.get(4)
-            if isReading:
-                workingPorts.append(devPort)
+            if is_reading:
+                working_ports.append(dev_port)
 
-        devPort += 1
+        dev_port += 1
 
-    return workingPorts
+    return working_ports
 
 
 class RosCamera(Node):
@@ -50,10 +48,11 @@ def __init__(self, topicName: str, camera: int):
         #        ex. topic message: "0 off", "0 on"
         # The topic message should always have the corresponding camera number
         # at the first index of each message.
-        subTopicName = "camera_control"
-        self.subscription = self.create_subscription(String, subTopicName, self.setCameraState, 10)
-        self.subscription
-        self.get_logger().info("Created Subscription to" + subTopicName)
+        sub_topic_name = "camera_control"
+        self.subscription = self.create_subscription(
+            String, sub_topic_name, self.setCameraState, 10
+        )
+        self.get_logger().info("Created Subscription to" + sub_topic_name)
 
         # We will publish a message every 0.1 seconds
         # timer_period = 0.1  # seconds
@@ -76,49 +75,49 @@ def __init__(self, topicName: str, camera: int):
         self.declare_parameter("cameraNumber", camera)
         self.declare_parameter("isOn", True)
 
-    """
-    Callback function publishes a frame captured from a camera to /video_framesX (X is specific
-    camera ID) every 0.1 seconds
-    """
+    def publishCameraFrame(self) -> None:
+        """
+        Callback function publishes a frame captured from a camera to /video_framesX (X is specific
+        camera ID) every 0.1 seconds
+        """
 
-    def publishCameraFrame(self):
         # Capture frame-by-frame
         # This method returns True/False as well as the video frame.
         ret, frame = self.cap.read()
 
         # Get bool parameter, isOn, and check the state of the camera to publish frame or not
         # Value of isOn is controlled by setCameraState()
-        isOn = bool(self.get_parameter("isOn")._value)
-        if ret and isOn:
+        is_on = bool(self.get_parameter("isOn")._value)
+        if ret and is_on:
             # Publish the image.
             self._publisher.publish(self.br.cv2_to_compressed_imgmsg(frame))
 
-    """
-    Function reads str msgs from topic, 'camera_control' (published by mission control), and
-    turns on/off the periodic publishing of frames by a certain camera
-    
-    Function is called whenever a msg is published to 'camera_control'
-    
-    Function assumes str msgs sent to 'camera_control' begin with a number and ends with an 'f'
-    (meaning off) or 'n' (meaning on)
-        ex.
-            "0 off" -> to turn off camera with id=0
-            "2 on" -> to turn on camera with id=2
-    """
+    def setCameraState(self, msg: String) -> None:
+        """
+        Function reads str msgs from topic, 'camera_control' (published by mission control), and
+        turns on/off the periodic publishing of frames by a certain camera
+
+        Function is called whenever a msg is published to 'camera_control'
+
+        Function assumes str msgs sent to 'camera_control' begin with a number and ends with an 'f'
+        (meaning off) or 'n' (meaning on)
+            ex.
+                "0 off" -> to turn off camera with id=0
+                "2 on" -> to turn on camera with id=2
+        """
 
-    def setCameraState(self, msg) -> None:
         # Check if this specific camera is targeted by mission control, stop the function otherwise
-        cameraNumber = int(self.get_parameter("cameraNumber")._value)
-        if int(msg.data[0]) != cameraNumber:
+        camera_number = int(self.get_parameter("cameraNumber")._value)
+        if int(msg.data[0]) != camera_number:
             return
 
         # Check if the desired camera state is already fulfilled, print and stop the function if so
-        cameraOn = bool(self.get_parameter("isOn")._value)
-        if str(msg.data[-1]) == "f" and not cameraOn:
-            self.get_logger().info("camera" + str(cameraNumber) + " is already off!")
+        camera_on = bool(self.get_parameter("isOn")._value)
+        if str(msg.data[-1]) == "f" and not camera_on:
+            self.get_logger().info("camera" + str(camera_number) + " is already off!")
             return
-        elif str(msg.data[-1]) == "n" and cameraOn:
-            self.get_logger().info("camera" + str(cameraNumber) + " is already on!")
+        elif str(msg.data[-1]) == "n" and camera_on:
+            self.get_logger().info("camera" + str(camera_number) + " is already on!")
             return
 
         # Set isOn bool parameter to either stop or restart the publishing of frames
@@ -131,20 +130,24 @@ def setCameraState(self, msg) -> None:
             self.declare_parameter("isOn", True)
 
 
-def main(args=None):
+def main(args: list[str] | None = None) -> None:
+    """
+    The entry point of the node.
+    """
+
     rclpy.init(args=args)
     try:
         # We need an executor because running .spin() is a blocking function.
         # using the MultiThreadedExecutor, we can control multiple nodes
         executor = MultiThreadedExecutor()
         nodes = []
-        cameraNum = 0
+        camera_num = 0
 
-        for cameraID in getCameras():
-            node = RosCamera("video_frames" + str(cameraNum), cameraID)
+        for camera_id in getCameras():
+            node = RosCamera("video_frames" + str(camera_num), camera_id)
             nodes.append(node)
             executor.add_node(node)
-            cameraNum += 1
+            camera_num += 1
 
         try:
             executor.spin()