muscle_node/getMuscle.js

node.js wrapper for MUSCLE alignment

/*
****Usage 
    node getMuscle.js 
    
    node will check your OS (Win or Mac) and download the correct binary; in the case of MacOS, node will unzip. Finally, node will rename the executable 'muscle' for simplicity 
  ***************************************************************  
*/

//require the following modules
var fs = require('fs');
var download = require('download');
var exec = require('child_process').exec;
//check if user is using Windows 
var isWin = /^win/.test(process.platform);
//build a commandline for unzipping the MacOS download
var unzipCommand = 'tar -zxvf muscle3.8.31_i86darwin64.tar.gz';

//function for Windows download that takes callback
function musclePC(Windows) {
    download('http://www.drive5.com/muscle/downloads3.8.31/muscle3.8.31_i86win32.exe', './').then(() => {
        console.log('\n' + ' downloaded executable');
        Windows();
    });
}

//function for MacOS download that takes 
//two functions to unzip and rename
function muscleMac(Mac, callback) {
    download('http://www.drive5.com/muscle/downloads3.8.31/muscle3.8.31_i86darwin64.tar.gz', './').then(() => {
        console.log('\n' + ' downloaded zipped executable');
        Mac(callback);
    });
}


if (isWin == true) {
    musclePC(function () {
        fs.rename('muscle3.8.31_i86win32.exe', 'muscle.exe', function (err) {
            if (err) throw err;
            fs.stat('muscle.exe', function (err, stats) {
                if (err) throw err;
                console.log('\n' + ' truncated executable filename to muscle');
            });
        });
    });
} else {

    muscleMac(function (callback) {
        exec(unzipCommand, function (error, stdout, stderr) {
            if (error != null) {
                console.log(stderr);
            }
            callback();
        });
        console.log('\n' + ' unzipped file...TODO add it to your PATH');

    }, function () {
        fs.renameSync('muscle3.8.31_i86darwin64', 'muscle');
        console.log('\n' + ' truncated executable filename to muscle' + '\n');
    });
}