Implement MQTT protocol

Dockerfile_Publisher

@@ -0,0 +1,7 @@
+FROM python:3.6.9
+
+COPY ./MassRobotics-AMR-MQTT-Client /app
+WORKDIR /app
+RUN pip install paho-mqtt
+
+ENTRYPOINT python publisher.py mqtt

MassRobotics-AMR-MQTT-Client/publisher.py

@@ -0,0 +1,98 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+import asyncio
+
+import paho.mqtt.client as mqtt
+import hashlib
+import uuid
+from datetime import datetime, timezone, timedelta
+import json
+import random
+import math
+import time
+import sys
+
+OPERATIONAL_STATES = ["navigating", "idle", "disabled", "offline", "charging",
+  "waitingHumanEvent", "waitingExternalEvent", "waitingInternalEvent", "manualOverride"]
+
+async def sendMessage(host, port, keepalive):
+    mqtt_client = mqtt.Client()
+    mqtt_client.connect(host, port, keepalive)
+    mqtt_client.loop_start()
+
+    # These could come from a configuration file or environment variables or any other source, but they are assumed not to change!
+    identity = {"manufacturerName": "Mass Robotics AMR", "robotModel": "AMR-01", "robotSerialNumber": "0000001", "baseRobotEnvelope": {"x": 0.5, "y": 1}}
+
+    # Generate a uuid that will be consistent for this robot
+    m = hashlib.md5()
+    seed = identity["manufacturerName"] + identity["robotSerialNumber"]
+    m.update(seed.encode('utf-8'))
+    uid = uuid.UUID(m.hexdigest())
+    identity["uuid"] = str(uid)
+
+    # Attach a timestamp
+    identity["timestamp"] = datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%S%z")
+
+    mqtt_client.publish("identityReport", json.dumps(identity))
+
+    status = {"uuid": str(uid)}
+    # status = {}
+    while True:
+      nowDt = datetime.now(timezone.utc)
+      now = nowDt.timestamp()
+      status["timestamp"] = nowDt.strftime("%Y-%m-%dT%H:%M:%S%z")
+
+      # The following information would need to be pulled out in a vendor-specific way,
+      # for this example it is just randomly generated
+
+      # Get the current operational state and put it in the status message
+      status["operationalState"] = random.choice(OPERATIONAL_STATES)
+
+      # Generate a battery percentage that goes between 20 and 100
+      status["batteryPercentage"] = 20 + now % 81
+
+      # Pick a random velocity
+      status["velocity"] = random.choice([
+        # deviating 10 degrees to the left
+        { "linear": 3, "angular": { "x": 0., "y": 0., "z": 0.087, "w": 0.996 } },
+        # deviating 15 degrees to the right
+        { "linear": 1, "angular": { "x": 0., "y": 0., "z": -0.131, "w": 0.991 } }
+      ])
+
+      # Generate a random location, simulating that the AMR moves in circles
+      r = 20
+      angle = random.choice([
+        { "x": 0., "y": 0., "z": 0.087, "w": 0.996 },
+        { "x": 0., "y": 0., "z": -0.131, "w": 0.991 }
+      ])
+      status["location"] = {"x":  math.cos(now) * r, "y": math.sin(now) * r, "z": 0, "angle": angle, "planarDatum": "4B8302DA-21AD-401F-AF45-1DFD956B80B5"}
+
+      # Generate random paths and destinations
+      side = random.choice([10, 20, 30])
+      status["path"] = [
+        {"timestamp": (nowDt+timedelta(seconds=10)).strftime("%Y-%m-%dT%H:%M:%S%z"), "x": 0, "y": 0, "angle": { "x": 0., "y": 0., "z": 0., "w": 1 }, "planarDatumUUID": "4B8302DA-21AD-401F-AF45-1DFD956B80B5"},
+        {"timestamp": (nowDt+timedelta(seconds=20)).strftime("%Y-%m-%dT%H:%M:%S%z"), "x": 0, "y": side, "angle": { "x": 0., "y": 0., "z": 0., "w": 1 }, "planarDatumUUID": "4B8302DA-21AD-401F-AF45-1DFD956B80B5"},
+        {"timestamp": (nowDt+timedelta(seconds=30)).strftime("%Y-%m-%dT%H:%M:%S%z"), "x": side, "y": side, "angle": { "x": 0., "y": 0., "z": 0., "w": 1 }, "planarDatumUUID": "4B8302DA-21AD-401F-AF45-1DFD956B80B5"},
+        {"timestamp": (nowDt+timedelta(seconds=40)).strftime("%Y-%m-%dT%H:%M:%S%z"), "x": side, "y": 0, "angle": { "x": 0., "y": 0., "z": 0., "w": 1 }, "planarDatumUUID": "4B8302DA-21AD-401F-AF45-1DFD956B80B5"},
+        {"timestamp": (nowDt+timedelta(seconds=50)).strftime("%Y-%m-%dT%H:%M:%S%z"), "x": 0, "y": 0, "angle": { "x": 0., "y": 0., "z": 0., "w": 1 }, "planarDatumUUID": "4B8302DA-21AD-401F-AF45-1DFD956B80B5"}
+      ]
+      status["destinations"] = [
+        {"timestamp": (nowDt+timedelta(seconds=30)).strftime("%Y-%m-%dT%H:%M:%S%z"), "x": side, "y": side, "angle": { "x": 0., "y": 0., "z": 0., "w": 1 }, "planarDatumUUID": "4B8302DA-21AD-401F-AF45-1DFD956B80B5"},
+        {"timestamp": (nowDt+timedelta(seconds=50)).strftime("%Y-%m-%dT%H:%M:%S%z"), "x": 0, "y": 0, "angle": { "x": 0., "y": 0., "z": 0., "w": 1 }, "planarDatumUUID": "4B8302DA-21AD-401F-AF45-1DFD956B80B5"}
+      ]
+
+      # Publish the report message
+      mqtt_client.publish("statusReport", json.dumps(status))
+      # mqtt_client.publish("identityReport", json.dumps(status))
+
+      # Wait for 1 second
+      time.sleep(1)
+
+if __name__ == '__main__':
+    host = "localhost"
+    if len(sys.argv) > 1:
+        host = sys.argv[1]
+    port = 1883
+    keepalive = 60
+    asyncio.get_event_loop().run_until_complete(sendMessage(host, port, keepalive))

MassRobotics-AMR-MQTT-Client/subscriber.py

@@ -0,0 +1,31 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+import paho.mqtt.client as mqtt
+import json
+from jsonschema import validate, ValidationError
+
+host = "localhost"
+port = 1883
+keepalive = 60
+
+with open('../AMR_Interop_Standard.json') as file_obj:
+    json_schema = json.load(file_obj)
+
+def on_message(mqttc, obj, msg):
+    print(msg.topic)
+    json_dict = json.loads(msg.payload)
+    try:
+        validate(json_dict, json_schema)
+        print(json_dict)
+    except ValidationError as e:
+        print(e.message)
+
+mqtt_client = mqtt.Client()
+mqtt_client.on_message = on_message
+mqtt_client.connect(host, port, keepalive)
+
+mqtt_client.subscribe("identityReport")
+mqtt_client.subscribe("statusReport")
+
+mqtt_client.loop_forever()

MassRobotics-AMR-Receiver/package.json

@@ -1,7 +1,7 @@
 {
   "name": "MassRobotics-AMR-Receiver",
-  "version": "0.1.0",
-  "description": "Application to validate the schema of websocket messages",
+  "version": "0.2.0",
+  "description": "Application to validate the schema of websocket messages and mqtt messages",
   "scripts": {
     "install-all": "npm install; gulp build;",
     "install-server": "npm install --only=prod",
@@ -48,6 +48,7 @@
     "body-parser": "1.18.0",
     "express": "4.15.4",
     "express-ws": "4.0.0",
+    "mqtt": "4.2.8",
     "underscore": "1.12.0"
   }
 }

MassRobotics-AMR-Receiver/server/services/server.js

@@ -6,8 +6,10 @@ const Ajv = require("ajv");
 const ajv = new Ajv({strictSchema: false});
 let validate = ajv.compile(schema);
 let UIsockets = {};
+const mqtt = require('mqtt');
+var mqtt_client;
 
-module.exports = function(app) {
+module.exports = function(app, mqtt_broker = "mosquitto") {
   app.use(bodyParser.json());
 
   app.ws('/ui', function(ws, req) {
@@ -43,6 +45,25 @@ module.exports = function(app) {
   app.get('/test-message', function(req, res) {
     res.send(testMessage);
   });
+
+  mqtt_client = mqtt.connect('mqtt://' + mqtt_broker);
+  mqtt_client.on('connect', function() {
+    mqtt_client.subscribe('identityReport', function (err) {
+      if (err) {
+	console.log("Error: identityReport subscribe");
+      }
+    });
+    mqtt_client.subscribe('statusReport', function (err) {
+      if (err) {
+	console.log("Error: statusReport subscribe");
+      }
+    });
+  });
+
+  mqtt_client.on('message', function (topic, message) {
+    console.log("subscribe : " + topic);
+    processMessage(message);
+  })
 };
 
 function processMessage(msg) {
@@ -75,6 +96,8 @@ function processMessage(msg) {
       errors: errors
     });
   });
+  // Issuing mqtt protocol is not necessary,
+  // because it is publish/subscribe type.
 }
 
 function sendMessage(ws, data = {}) {

docker-compose.yml

@@ -7,6 +7,8 @@ services:
       context: .
       dockerfile: Dockerfile_Receiver
     container_name: receiver
+    depends_on:
+      - "mqtt"
     ports:
       - "3000:3000"
     volumes:
@@ -21,5 +23,20 @@ services:
     depends_on:
       - "receiver"
     tty: true
+  mqtt:
+    build: ./mosquitto
+    hostname: mosquitto
+    container_name: mqtt
+    ports:
+      - "1883:1883"
+  publisher:
+    image: publisher
+    build:
+      context: .
+      dockerfile: Dockerfile_Publisher
+    container_name: publisher
+    depends_on:
+      - "receiver"
+    tty: true
 volumes:
   node_modules:

mosquitto/Dockerfile

@@ -0,0 +1,3 @@
+FROM eclipse-mosquitto
+
+COPY ./mosquitto.conf /mosquitto/config

mosquitto/mosquitto.conf

@@ -0,0 +1,6 @@
+allow_anonymous true
+
+persistence true
+persistence_location /mosquitto/data/
+
+listener 1883