pelioniot / devicejs-examples

Examples for DeviceJS

DeviceJS Examples

Auto Increment Example

We will start a DeviceJS instance with an "ExampleDiscoverer" which will discover three "ExampleDeviceThatEmits" devices.

1. Install DeviceJS if you have not already done so.
   This example
2. start DeviceJS using the ExampleDeviceThatEmits.conf.json config file. In the newly cloned directory of devicejs-example, run:

   sudo [devicejs-location]/bin/devjs -vvvv --start --id test -c conf/ExampleDeviceThatEmits.conf.json

where [devicejs-location] is where DeviceJS is installed.

This will start DeviceJS with a large amount of debugging output, running under the instance name "test". You can verify the instance is running from another terminal by typing:

$ sudo ~/work/devicejs/bin/devjs --show
DeviceJS running instances:
  ID						State
  test	S

3. Now we can connect to this running instance over a shell. The shell is useful for trying out commands and debugging applications. It uses the same node.js REPL facilities just like [this](http://blog.modulus.io/absolute-beginners-guide-to-nodejs), when you type node at the prompt. To shell in you need to specify the DeviceJS instance:

$ sudo ~/work/devicejs/bin/devjs --shell --id test
2014-12-28T02:14:50.241Z  exec/runtimeIpc.js:239 (sendControlResponseCB) res is { r: 'ready',
  p: '/home/ed/work/devicejs/var/1141127-11329-p576wq_repl' }
Shell into DevJS instance /home/ed/work/devicejs/var/1141127-11329-p576wq_repl
2014-12-28T02:14:50.245Z  exec/devjsREPL.js:61 (clientConnect) path: /home/ed/work/devicejs/var/1141127-11329-p576wq_repl
2014-12-28T02:14:50.248Z  exec/devjsREPL.js:79 (Socket.) connected.
devjs[test]> 

The DeviceJS devjs[test]> prompt tells you that you are shelled into the DeviceJS instance "test". Notice if you type dev$ and *enter* the DeviceJS global selector will be dumped to the console. 4. Now we can test out the example code.

devjs[test]> dev$.selectByFacade("ExampleHappened")

The function returns an object which can act on devices with the Facade "ExampleHappened". Notice the deviceMap area - which will have three unique IDs:

     ...
     deviceMap: 
      { 'b5b1f308-cacc-4d70-8f0b-b5c437f00a20': [Object],     
        '82bad9ef-094e-416b-9493-ab7c0a73c1de': [Object],
        '55d3bb83-5ecf-4ea2-8b0c-6e6bbb12b342': [Object] },
     ...

These are the three UUID of the devices created by the ExampleDiscoverer class.
The example device class ExampleDeviceThatEmits implements a Facade ExampleHappened.

devjs[test]> dev$.selectByID("b5b1f308-cacc-4d70-8f0b-b5c437f00a20").device().special();
100  (or some other number if you have ran the example before)

This is the value 'special' for the device. 5. Now let's run a method of the ExampleDeviceThatEmits class. This method will start making the device changing the special value periodically:

devjs[test]> dev$.selectByID("b5b1f308-cacc-4d70-8f0b-b5c437f00a20").device().autoIncrementSpecial();
undefined

Now look at the *special* value change over time. Note: this value is being stored automatically to the database... so if you kill DeviceJS and restart, the value will be where it was.

devjs[test]> dev$.selectByID("b5b1f308-cacc-4d70-8f0b-b5c437f00a20").device().special()
1415
devjs[test]> dev$.selectByID("b5b1f308-cacc-4d70-8f0b-b5c437f00a20").device().special()
1415
devjs[test]> dev$.selectByID("b5b1f308-cacc-4d70-8f0b-b5c437f00a20").device().special()
1415
devjs[test]> dev$.selectByID("b5b1f308-cacc-4d70-8f0b-b5c437f00a20").device().special()
1416
devjs[test]> dev$.selectByID("b5b1f308-cacc-4d70-8f0b-b5c437f00a20").device().special()
1416
devjs[test]> dev$.selectByID("b5b1f308-cacc-4d70-8f0b-b5c437f00a20").device().special()
1416
devjs[test]> dev$.selectByID("b5b1f308-cacc-4d70-8f0b-b5c437f00a20").device().special()
1418