find protractor selenium jar

gulpfile.js

var gulp = require('gulp');
var lib = require('./lib');
var protractor = require("gulp-protractor").protractor;

var jarPath = lib.getProtractorSeleniumJarPath();

gulp.task('default', function(){
    gulp.src(["./spec/*.js"])
        .pipe(protractor({
            configFile: "protractor.config.js",
            args: [
                '--seleniumServerJar', jarPath
            ]
        }))
        .on('error', function(e) { throw e })
});

lib.index.js

var glob = require('glob');

module.exports = {

    getProtractorSeleniumJarPath: function() {
        var jarPath = glob.sync('node_modules/protractor/selenium/selenium-server-standalone-*.jar')[0];
        console.log(jarPath);
        return jarPath;
    }
};

npmrc.sh

npm config set http_proxy test
npm config set https_proxy test