Serverless IOT Offline

Serverless plugin that emulates AWS IoT service

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Serverless plugin that emulates AWS IoT service. Manages topic subscriptions, lifecycle events, thing shadow management and rule engine with limited SQL syntax support.


Redis installed.
Serverless framework 1.x


Add serverless-iot-offline to your project:
npm install --save-dev serverless-iot-offline
Then inside yur serverless.yml file add following entry to the plugins section: serverless-iot-offline. If there is no plugin section you will need to add it to the file.

  - serverless-iot-offline

or if you are using serverless-offline plugin:

  - serverless-iot-offline
  - serverless-offline

If you are using serverless-offline v5.12.1 and below, use serverless-iot-offline@0.1.4 for comaptibility.

Usage and command line options

Make sure redis-server is started.
If you are using serverless-offline you can run:
sls offline start
Otherwise run:
sls iot start

CLI options:

--port                -p  # Port to listen on. Default: 1883
--httpPort            -h  # Port for WebSocket connections. Default: 1884
--noStart             -n  # Prevent Iot broker (Mosca MQTT brorker) from being started (if you already have one)
--skipCacheValidation -c  # Tells the plugin to skip require cache invalidation. A script reloading tool like Nodemon might then be needed (same as serverless-offline)

Above options could be added through serverless.yml file:

      port: 1880
      host: 'localhost'
      port: 6379
      db: 12
    # path to initial shadows
    # it is used to seed redis database with preconfigured shadows
    seedShadows: ./shadows.json
    # optional seedPolicies path
    seedPolicies: ./policy.json

Example of shadows.json file which will seed redis with 2 shadows:

  "thingName1": {
    "state": {
      "reported": {
        "some_prop": "hello"
  "thingName2": {
    "state": {
      "reported": {}


Local implementation of AWS IoT service has a minimum of SQL syntax support and primarily we need help with that.
To get a better understanding of what SQL syntax we are supporting see documentation and testData.js file.
Checkout contributing guidelines.

Credits and inspiration

This plugin was inspired by Tradle's serverless-iot-local project