README.md

duktape-node

Simple Duktape Javascript engine integration for node.js.

This package provides facilities for running a single script on an isolated Duktape virtual machine.

Package has been tested on linux and should be compatible with node.js versions: 0.10.x, 0.11.x, 0.12.x and 4.x.

Installing

npm install duktape

Building manually and running tests

git clone https://github.com/ndob/duktape-node.git
cd duktape-node
git submodule init
git submodule update
npm install
npm test

API

run(functionName, parameter, script, apiObject, callback)

Description

Runs a single script on duktape and returns error status and return value to callback.

Parameters

• functionName: function to run (string)
• parameter: parameter for function (string)
• script: whole javascript source of script (string)
• apiObject: API for script (object)
  • properties:
    • key: name for function
    • value: function to call
• callback: function with signature function(error, returnValue)
  • error: error status (boolean)
  • returnValue: return value from script (string) or error string in case of an error

Example

var duktape = require('duktape');

var apiFunction = function(name) {
    return "hello " + name;
}

var script = " \
  function helloFun(parameterString) { \
    return { \
      value: hello(parameterString), \
      extra: 'bye ' + parameterString \
    }; \
  }";

var apiObject = {
    hello: apiFunction
};
  
duktape.run("helloFun", "world", script, apiObject, function(error, ret) {
  if(error) {
    console.log("got error: " + ret);
  } else {
    var retVal = JSON.parse(ret);
    console.log(retVal.value);
    console.log(retVal.extra);
  }
});

runSync(functionName, parameter, script, apiObject)

Description

Runs a single script on duktape and returns script's return value. Errors are handled by exceptions. Otherwise functionality is the same as in async-version.

Parameters

• functionName: function to run (string)
• parameter: parameter for function (string)
• script: whole javascript source of script (string)
• apiObject: API for script (object)
  • properties:
    • key: name for function
    • value: function to call

Example

var duktape = require('duktape');

var apiFunction = function(name) {
    return "hello " + name;
}

var apiObject = {
    hello: apiFunction
};

var script = " \
  function helloFun(parameterString) { \
    return { \
      value: hello(parameterString), \
      extra: 'bye ' + parameterString \
    }; \
  }";
  
try {
  var ret = duktape.runSync("helloFun", "world", script, apiObject);
  var retVal = JSON.parse(ret);
  console.log(retVal.value);
  console.log(retVal.extra);
} catch(error) {
  console.log("got error" + error);
}

What this package doesn't do

This package just runs scripts on duktape VM without doing much else. Everything listed here is left for host programs responsibility.

• Limit resources (memory, cpu time, etc.)
• Input parameters and return values
  • Sanity checks
  • Formatting

Known issues

• To use this package with node 4.0.0 you should build with gcc version >= 4.8 or clang >= 3.4.
• No async support from defined API-functions back to duktape (ie. no callbacks).