Adds MQTT_controller and MQTT_interface implementing tcp interface for interaction through MQTT

mqtt_controller.py

+import json
+
+import paho.mqtt.client as mqtt
+import paho.mqtt.publish as publish
+from config import MQTT_CONTROL_CONFIG, OHMPI_CONFIG
+import time
+import uuid
+
+client = mqtt.Client(f'ohmpi_{OHMPI_CONFIG["id"]}_controller')  # create new instance
+print('connecting to broker')
+client.connect(MQTT_CONTROL_CONFIG['hostname'])
+client.loop_start()
+publisher_config = MQTT_CONTROL_CONFIG.copy()
+publisher_config['topic'] = MQTT_CONTROL_CONFIG['ctrl_topic']
+publisher_config.pop('ctrl_topic')
+settings = {
+            'injection_duration': 0.2,
+            'nbr_meas': 100,
+            'sequence_delay': 1,
+            'nb_stack': 1,
+            'export_path': 'data/measurement.csv'
+        }
+
+cmd_id = uuid.uuid4().hex
+payload = json.dumps({'cmd_id': cmd_id, 'cmd': 'update_settings', 'args': settings})
+print(f'Update settings setup message: {payload} to {publisher_config["topic"]} with config {publisher_config}')
+publish.single(payload=payload, **publisher_config)
+
+sequence = [[1, 2, 3, 4]]
+cmd_id = uuid.uuid4().hex
+payload = json.dumps({'cmd_id': cmd_id, 'cmd': 'set_sequence', 'args': sequence})
+print(f'Set sequence message: {payload} to {publisher_config["topic"]} with config {publisher_config}')
+publish.single(payload=payload, **publisher_config)
+for i in range(4):
+    cmd_id = uuid.uuid4().hex
+    payload = json.dumps({'cmd_id': cmd_id, 'cmd': 'start'})
+    print(f'Publishing message {i}: {payload} to {publisher_config["topic"]} with config {publisher_config}')
+    publish.single(payload=payload, **publisher_config)
+    time.sleep(1)
+client.loop_stop()

mqtt_interface.py

+import paho.mqtt.client as mqtt
+from config import MQTT_CONTROL_CONFIG, CONTROL_CONFIG, OHMPI_CONFIG
+import time
+from queue import Queue
+import zmq
+
+ctrl_queue = Queue()
+
+
+def on_message(client, userdata, message):
+    global socket
+
+    # Send the command
+    print(f'Sending command {message.payload.decode("utf-8")}')
+    socket.send_string(message.payload.decode("utf-8"))
+
+    #  Get the reply.
+    reply = socket.recv()
+    print(f'Received reply {message.payload.decode("utf-8")}: {reply}')
+
+
+mqtt_client = mqtt.Client(f'ohmpi_{OHMPI_CONFIG["id"]}_listener')  # create new instance
+print('connecting to broker')
+mqtt_client.connect(MQTT_CONTROL_CONFIG['hostname'])
+print('Subscribing to topic', MQTT_CONTROL_CONFIG['ctrl_topic'])
+mqtt_client.subscribe(MQTT_CONTROL_CONFIG['ctrl_topic'], MQTT_CONTROL_CONFIG['qos'])
+mqtt_client.on_message = on_message
+mqtt_client.loop_start()
+context = zmq.Context()
+
+#  Socket to talk to server
+print("Connecting to ohmpi control server")
+socket = context.socket(zmq.REQ)
+socket.connect(f'tcp://localhost:{CONTROL_CONFIG["tcp_port"]}')
+
+while True:
+    time.sleep(.1)