@droneblocks/node-red-dexi/src/servo.js

You want to make sure you don't lose any of your flow development. Make sure to map the host "flows" directory to the container directory as shown below. This will store the flow on your host machine if/when the container is destroyed.

module.exports = function(RED) {
    function ServoNode(config) {
        RED.nodes.createNode(this, config);
        var node = this;
        node.name = config.name;
        node.servoId = parseInt(config.servoId);
        node.angle = parseInt(config.angle);

        node.on('input', function(msg) {
            var servoId = node.servoId;
            var angle = node.angle;

            // Check if angle was passed as a simple number (e.g., from a slider)
            // Only accept numbers in valid servo range (0-180)
            if (typeof msg.payload === 'number' && msg.payload >= 0 && msg.payload <= 180) {
                angle = parseInt(msg.payload);
            }
            // Check if servo parameters were passed as an object
            else if (typeof msg.payload === 'object') {
                if (typeof msg.payload.servoId !== 'undefined') {
                    servoId = parseInt(msg.payload.servoId);
                }
                if (typeof msg.payload.angle !== 'undefined') {
                    angle = parseInt(msg.payload.angle);
                }
            }
            // Otherwise use configured values (handles inject timestamps, etc.)

            msg.payload = {
                "serviceName": "/dexi/servo_control",
                "serviceType": "dexi_interfaces/srv/ServoControl",
                "serviceRequest": {
                    "pin": servoId,
                    "angle": angle
                }
            }
            node.send(msg);
        });
    }

    RED.nodes.registerType("servo", ServoNode);
}