bonnet

bonnet

Bonnet is a simple tool for distributing your long running blocking tasks in time using ES6 generators in node.

Using Bonnet you are able to split your computation into pieces with yield and in the end return your result. Bonnet returns a promise and resolves it, if your function finished or rejects it, if you throw an error. The benefit of this is that you won't block your event loop if you are working on small fast parts.

Installation

$ npm install bonnet

And after:

var bonnet = require('bonnet');
bonnet(myGenerator);

How to use

Simple example

var bonnet = require('bonnet');
bonnet(function* () {
     var sum = 0;
     for (var i = 0; i <= 10000; i++) {
            yield sum = sum + i;
     }
     return sum;
}).then(function (data) {
    console.log(data);
}, function (error) {
    console.log(error);
});

Combine with promises

var bonnet = require('bonnet');
var Promise = require('promise');


function myAsynchronousTask() {
    return new Promise(function (resolve, reject) {
        setTimeout(function () {
            resolve("bar");
        }, 10);
    });
}

bonnet(function* () {
    var result = "foo";
    result += yield myAsynchronousTask();
    result += yield "foo";
    return result;
}).then(function (data) {
    console.log(data); //foobarfoo
});

Error handling

var bonnet = require('bonnet');
bonnet(function* () {
    var somethingWrong = true;
    if(somethingWrong){
       throw new Error("ERROR");
    }  
}).then(null, function (error) {
    console.log(error);
});

Wrapper

var wrap = require('bonnet').wrap;
var wrappedFunction = wrap(function* (a,b) {
      var str = "";
      for (var i=0; i<=10000; i++){
        str =  yield (new Array(5)).join(b);
      }
      return a+str;
});

wrappedFunction("foo","bar").then(function(data){
    console.log(data);  //foobarbarbarbar
});

Test

  $ npm test