IOT IO Library

A unified Javascript IO library for IOT device(Galileo/Edison), companion device(phone/tablet) and XDK.

Components

• Two libraries: iot-io, iot-io-companion
• A server: iot-io-server
• An automation tool: autogen

iot-io

A Javascript based IO library which provides Arduino like APIs.

The target execution environment is IOT devices including Galileo and Edison

iot-io-companion

Remotely call iot-io built-in Arduino like functions and user-defined functions. The function call will be translated to a JSON-RPC request and the iot-io-server will receive the request then call iot-io library natively.

The target execution environment is companion devices including phone/tablet/pc/etc. This library can run in Nodejs or browser.

iot-io-server

A JSON-RPC server can expose iot-io's Arduino like APIs and even user defined functions to remote companion devices.

Basically its target execution environment is IOT device.

autogen

It is a Python tool. Its input is standard C header file and its output is the main skeleton of iot-io/iot-io-companion/iot-io-server. When user wants to add C/C++ functions as new interfaces to io-js software stack he doesn't need to learn any C to JS binding. This tool can help this javascript library adapt to the changes of C/C++ library.

Prebuild

If you only want to build some of components, please go to the corresponding directory and read the README. Below instruction is about how to build the whole software stack.

• Please follow the document Intel Galileo Getting Started to install Yocto on Galileo and boot your board from a SD card

• Because SD card image does not contain development tools such as gcc, g++ etc, then we have to do cross build. Then please prepare a Linux machine and install below tools.

• Install node-gyp. Please notice node-gyp will detect the version of local nodejs and automatically download some header files and libraries for compilation. Then please make sure the version of nodejs on host machine is the same as which of nodejs on Galileo. If you do not want to the keep the nodejs version. You can manually open target/device/Makefile and added the version of target nodejs on Galileo.

rebuild:
    node-gyp rebuild --arch=ia32 --target=0.x.x

configure:
    node-gyp configure  --arch=ia32 --target=0.x.x

• Install cross compiler

  • The Galileo Arduino IDE has contained a cross compiler, please download the Linux version from https://communities.intel.com/docs/DOC-22226 to your host Linux machine

  • Edit target/device/set_cross_compiler.sh and set ARDUINO_PATH to the right path

  • run the script to set environment values

source target/device/set_cross_compiler.sh

• Optionally install uglify for Javascript library compressing and mangling

sudo npm install -g uglify-js

• Optionally install jsdoc for document generation

sudo npm install -g jsdoc

Build

Build with npm and install dependent libraries

npm install

Quick Start

Control IO with Javascript on IOT device

With iot-io library programmer can develop the program with Javascript to control IO. The API is Arduino like and easy to understand.

For example we can turn on a LED on digital pin 13 with below file

var IOLIB = require('iot-io');
var io = new IOLIB.IO({
  log: true
});

io.pinMode(13, io.OUTPUT);
io.digitalWrite(13, io.HIGH);

Or you can use high level APIs which have hidden some hardware details. For above example, you can use API of Led

var IOLIB = require('iot-io');
var io = new IOLIB.IO({
  log: true
});

var led = new IOLIB.Led({
  io: io,
  pin: 13
});

led.on();

Remote IO Control

We can use all of iot-io APIs as RPC(Remote Procdure call) functions with iot-io-companion. The below code can remotely turn on the LED from another machine. The only difference to above example is we must set extra options to tell where remote RPC server is. Please save below codes to file led_rpc.js on remote PC. The first line is to make sure this library can be loaded in nodejs and browser.

var IOLIB = (typeof require === 'function') ?
            require('iot-io-companion'): this.IOLIB;

var io = new IOLIB.IO({
  log: true,
  rpc: true,  // turn on rpc call
  port: 2000, // port of RPC server
  hostname: '192.168.2.11', //address or machine name of RPC server
});

var led = new IOLIB.Led({
  io: io,
  pin: 13
});

led.on();

On IOT device please install and run iot-io-server to expose built-in APIs

npm install -g iot-io-server
iot-io-server

Back to your remote machine and run led_rpc.js to turn on the LED on IOT device.

node led_rpc.js

Run in Browser

The remote control codes can run in browser & nodejs. Because iot-io-companion library for browser is based on jQuery please load jQuery firstly. You can create a HTML file led_rpc.html and put it in the directory in which led_rpc.js is.

<script src='http://code.jquery.com/jquery-1.11.0.min.js'> </script>
<script src='./iot-io-browser-general.js'></script>
<script src='./led_rpc.js'></script>

Then you can open led_rpc.html in browser and LED on IOT device will be turned on

Pack it to mobile APP

The above HTML page can be packed to an Android/iOS/WP/Tizen/... application with Intel XDK. You can create a project in XDK and import above index.html with libraries. You can also debug the application with XDK.

Expose user defined function

The iot-io-server can expose not only built-in APIs but also user defined functions.

Prepare the file which contains expose candidate. User defined functions are saved in global variable expose's member: RPC. A global variable isRpcServer can help determine whether this file is opened by iot-io-server.

var Foo = function(s) {
  console.log('hello ' + s);
};

if(isRpcServer) {
  exports.RPC = {
    'myFun': Foo
  };
}

Load it with iot-io-server

iot-io-server extra.js

The client side can use exposed function myFun in nodejs or browser after called io.addRpc.

var IOLIB = (typeof require === 'function') ? 
            require('iot-io-companion'): this.IOLIB;

var io = new IOLIB.IO({
  rpc: true,
  port: 2000,
  hostname: 'localhost',
});

io.addRpc('myFun');

myFun('world'); //will output 'hello world'

Add C/C++ function with autogen

With autogen tool programmer can easily translate C/C++ function to Javascript functions. Suppose user has a new function myPrint in my_print.cpp

void myPrint(char *s) {
  printf("hello %s\n", s);
}

In my_print.h the function myPrint is declared as extern

extern void myPrint(char *s);

Go to target/device/libio and put these two files under directory src, then add .cpp file to libio.gyp

      'extra_srcs' : [
        '<(extra_dir)/my_print.cpp',
      ],

add .h file to export.gyp

      'export_headers' : [
        '<(extra_dir)/my_print.h',
      ],

Finally go to the root directory and rebuild the whole software stack

cd io-js
make

Arduino like APIs

Currently there are more than 100 APIs which are translated from the Intel Galileo Arduino SW with autogen tool. Please read the [API document] (http://ilc-opensource.github.io/io-js/doc) to know more details

Test

• Test functionality with buster.js

make test

• Test autogen parser

./test_autogen

Directories

Directory	Description
/target/device	iot-io
/target/device/libio	Arduino library
/target/companion	iot-io-companion
/target/server	iot-io-server
/target/extension	high level APIs for iot-io & iot-io-companion
/util/autogen	autogen tool
/doc	documents. This directory will be created by jsdoc

License

All of components use the BSD license