5.1.1.3. incoming_order_handler

This node is used to handle the job of processing the new order placed.

Node to handle any new order placed on MQTT topic. This node process the order and add details like priority, cost, team ID and unique ID to the JSON object and sends it to UR5_1 arm for use via ROS topic. This node subscribes to ROS topic ‘/ros_iot_bridge/mqtt/sub’ where anything published on MQTT topic is published to get the details of the new order placed. After this a callback new_order_callback() do the processing of the order and send it to UR5_1 arm for use.

class incoming_order_handler.RosIotBridgeActionClient

Action Client to act as a bridge between ROS Nodes and IOT to update google spreadsheets

on_transition(goal_handle)

This function will be called when there is change of state in the Action Client State Machine

Parameters:goal_handle – unique id of goal Returns:None

send_goal(arg_protocol, arg_mode, arg_topic, arg_message)

This function is used to send Goals to Action Server

Parameters:

• arg_protocol (str) – IoT protocol to follow (HTTP, MQTT, etc.)
• arg_mode (str) – Mode whether to publish or subscribe
• arg_topic (str) – Topic to subscribe or publish to
• arg_message (str) – Message to push or publish

Returns:

goal handle

incoming_order_handler.main()

Main function to initialize nodes, action client, subscriber and publisher to handle new order placed on MQTT topic

incoming_order_handler.new_order_callback(msg, args)

Whenever a new order is placed on MQTT topic, this function is called to process the order details and send it to UR5_1 arm via ROS topic.

Parameters:

• msg (msgMqttSub) – Contains the details of new order.
• args (list) – list of Action Client and New order publisher.