@dojot/iotagent-nodejs
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    3.0.3 • Public • Published

    dojot IoT agent base library npm version

    This library contains all common operations that a IoT agent might need from dojot. This includes receiving notifications related to device operations, such as creation, deletion and updates, as well as methods for sending device data to other components.

    Attention: As of version v3.0, this library no longer has integration with the old "auth" service, but with the "keycloak" service. Be aware that the environment variables KEYCLOAK_USER and KEYCLOAK_PASSWORD will probably have to be passed to services that use this library. This user should be able to get the existing realm lists from keycloak.

    How to install

    Just execute

    npm install @dojot/iotagent-nodejs

    How to use

    This library has one main function, which is updateAttrs. Furthermore, it also generated events "device.create", "device.remove", "device.update", and "device.configure" in "iotagent.device" subject. The updateAttrs function and all events are shown in the folloing code.

    var iotagentLib = require('@dojot/iotagent-nodejs');
    var logger = require("@dojot/dojot-module-logger").logger;
    var util = require("util");
    
    logger.debug("Initializing IoT agent...");
    var iotagent = new iotagentLib.IoTAgent();
    iotagent.init().then(() => {
        logger.debug("... IoT agent was initialized");
    
        logger.debug("Registering callbacks for device events...");
        let deviceId = undefined;
        iotagent.on('iotagent.device', 'device.create', (tenant, event) => {
            logger.debug(`Got device creation message. Tenant is ${tenant}.`);
            logger.debug(`Data is: ${util.inspect(event)}`);
            logger.debug('Got configure event from Device Manager', event)
            // This is just to get one valid device ID to be used in
            // updateAttrs sample.
            deviceId = event.data.id;
        });
    
        iotagent.on('iotagent.device', 'device.configure', (tenant, event) => {
            logger.debug(`Got device actuation message. Tenant is ${tenant}.`);
            logger.debug(`Data is: ${util.inspect(event)}`);
            logger.debug('Got configure event from Device Manager', event)
        });
    
        iotagent.on('iotagent.device', 'device.remove', (tenant, event) => {
            logger.debug(`Got device removal message. Tenant is ${tenant}.`);
            logger.debug(`Data is: ${util.inspect(event)}`);
            logger.debug('Got configure event from Device Manager', event)
        });
    
        iotagent.on('iotagent.device', 'device.update', (tenant, event) => {
            logger.debug(`Got device update message. Tenant is ${tenant}.`);
            logger.debug(`Data is: ${util.inspect(event)}`);
            logger.debug('Got configure event from Device Manager')
        });
    
        logger.debug("... callbacks for device events were registered.")
    
        // If there is any configured device, the callback associated to "device.create"
        // event will be called.
        logger.debug("Requesting library to generate event for each device...")
        iotagent.messenger.generateDeviceCreateEventForActiveDevices();
        logger.debug("... event generation was requested.")
    
        let i = 0;
        const sendMessage = () => {
          i++;
          let msg = {
              "attr1": `this is a sample reading: ${i}`,
          };
          let metadata = {
    
          };
          if (deviceId != undefined) {
            iotagent.updateAttrs(deviceId, "admin", msg, metadata);
          }
          setTimeout(() => {
            sendMessage();
          }, 2000);
        };
    
        sendMessage();
    });

    Device events have the following format:

    • device.create:
    {
      "event": "create",
      "meta": {
        "service": "admin"
      },
      "data": {
        "id": "efac",
        "label" : "Device 1",
        "templates" : [ 1, 2, 3],
        "attrs" : {
    
        },
        "created" : "2018-02-06T10:43:40.890330+00:00"
      }
    }
    • device.update:
    {
      "event": "update",
      "meta": {
        "service": "admin"
      },
      "data": {
        "id": "efac",
        "label" : "Device 1",
        "templates" : [ 1, 2, 3],
        "attrs" : {
    
        },
        "created" : "2018-02-06T10:43:40.890330+00:00"
      }
    }
    • device.remove:
    {
      "event": "remove",
      "meta": {
        "service": "admin"
      },
      "data": {
        "id": "efac"
      }
    }
    • device.configure:
    {
      "event": "configure",
      "meta": {
        "service": "admin"
      },
      "data" : {
        "id" : "efac",
        "attrs": {
          "reset" : 1,
          "step-motor" : "+45"
        }
      }
    }

    In order to execute this code, the following environment variables can be set:

    # These are the default values
    export KAFKA_HOSTS="kafka:9092"
    export KAFKA_GROUP_ID="iotagent"
    export DATA_BROKER_URL="http://data-broker"
    export KEYCLOAK_URL="http://keycloak:8080/auth"
    export DEVICE_MANAGER_URL="http://device-manager:5000"

    It is important to notice that KAFKA_GROUP_ID variable must be set to something different, as this is used by Kafka to select which clients will receive messages from a particular topic. If not set, all services that uses the same ID will be selected at random to receive messages, which is probably not what you want.

    Keywords

    Install

    npm i @dojot/iotagent-nodejs

    DownloadsWeekly Downloads

    5

    Version

    3.0.3

    License

    Apache-2.0

    Unpacked Size

    60.5 kB

    Total Files

    13

    Last publish

    Collaborators

    • thiagodpf
    • manuel.gavidia
    • giovannicuriel
    • mprevide
    • scaraficci
    • timedojot