motto

Modular otto

Motto provide a Nodejs like module environment to run javascript files in golang.

Installation

go get github.com/ddliu/motto

Usage

var _ = require('underscore');
var data = require('./data.json'); // [3, 2, 1, 4, 6]
module.exports = _.min(data);

package main

import (
    "github.com/ddliu/motto"
    _ "github.com/ddliu/motto/underscore"
)

func main() {
    motto.Run("path/to/index.js")
}

You can also install the motto command line tool to run it directly:

go install github.com/ddliu/motto/motto
motto path/to/index.js

Modules

The module environment is almost capable with Nodejs spec.

Some Nodejs modules(without core module dependencies) can be used directly in Motto.

Addons

Motto can be extended with addons, below is an example addon which implement part of the "fs" module of Nodejs:

package fs

import (
    "github.com/ddliu/motto"
    "github.com/robertkrimen/otto"
)

func fsModuleLoader(vm *motto.Motto) (otto.Value, error) {
    fs, _ := vm.Object(`({})`)
    fs.Set("readFileSync", func(call otto.FunctionCall) otto.Value {
        filename, _ := call.Argument(0).ToString()
        bytes, err := ioutil.ReadFile(filename)
        if err != nil {
            return otto.UndefinedValue()
        }

        v, _ := call.Otto.ToValue(string(bytes))
        return v
    })

    return vm.ToValue(fs)
}

func init() {
    motto.AddModule("fs", fsModuleLoader)
}

After import this package, you can require it directly in your js file:

var fs = require('fs');
var content = fs.readFileSync('/path/to/data');

Nodejs in Golang?

nodego implements some features and core modules of Nodejs.

Performance

Simple benchmark shows below for furthur performance optimize:

strace -c -Ttt motto tests/index.js
strace -c -Ttt node tests/index.js

Motto:

% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
 20.20    0.000144           2        59           rt_sigaction
 15.71    0.000112           7        15           mmap
 11.92    0.000085          11         8           futex
 10.10    0.000072           6        13         4 stat
  7.43    0.000053           7         8           read
  5.89    0.000042          21         2           clone
  5.75    0.000041          10         4           open
  4.77    0.000034           7         5           rt_sigprocmask
  4.63    0.000033          33         1           execve
  3.23    0.000023          12         2           write
  2.24    0.000016           4         4           fstat
  1.82    0.000013           3         4           close
  1.82    0.000013          13         1           sched_getaffinity
  1.68    0.000012          12         1           sched_yield
  0.98    0.000007           7         1           munmap
  0.98    0.000007           7         1           arch_prctl
  0.42    0.000003           3         1           getcwd
  0.42    0.000003           3         1           sigaltstack
------ ----------- ----------- --------- --------- ----------------
100.00    0.000713                   131         4 total

Nodejs:

% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
 20.15    0.000636           7        92           mmap
 17.78    0.000561          16        36           munmap
 13.97    0.000441          18        24           read
  7.73    0.000244           7        35           mprotect
  7.70    0.000243          15        16           brk
  7.32    0.000231           7        34         1 futex
  4.56    0.000144           7        22           open
  3.61    0.000114           5        22        15 ioctl
  2.15    0.000068           3        21           close
  2.03    0.000064           3        21           fstat
  2.00    0.000063           5        14        14 access
  1.58    0.000050           4        12           lstat
  1.24    0.000039           8         5           write
  1.24    0.000039           6         7           rt_sigaction
  1.05    0.000033           6         6         2 stat
  0.89    0.000028          28         1           readlink
  0.76    0.000024           5         5           rt_sigprocmask
  0.70    0.000022           6         4           getcwd
  0.67    0.000021          11         2           pipe2
  0.63    0.000020          20         1           clone
  0.38    0.000012           6         2           getrlimit
  0.29    0.000009           9         1           epoll_create1
  0.25    0.000008           8         1           eventfd2
  0.22    0.000007           7         1           clock_gettime
  0.22    0.000007           4         2           epoll_ctl
  0.19    0.000006           6         1           gettid
  0.19    0.000006           6         1           set_tid_address
  0.19    0.000006           6         1           set_robust_list
  0.13    0.000004           4         1           execve
  0.10    0.000003           3         1           arch_prctl
  0.10    0.000003           3         1           epoll_wait
------ ----------- ----------- --------- --------- ----------------
100.00    0.003156                   393        32 total

Changelog

v0.1.0 (2014-06-22)

Initial release

v0.2.0 (2014-06-24)

Make module capable with Nodejs

v0.3.0 (2014-06-26)

Rewrite module.

Make it easier to write addons.

Add underscore addon as an example.