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Syncing files from one directory to another in Node?

I was using cpy with a globbing pattern to find and copy all the files in src/main/css and place them in ./dist.
However now I also have sub directories below src/main/css (For example src/main/css/margins/index.css) and cpy does not include these when copying the files.
Is there an API in Node (fs or path?) that handles this case, or anyone know of a handy package?

Try this.
const fs = require('fs');
const path = require('path');
var mkdir = function (dir) {
// making directory without exception if exists
try {
fs.mkdirSync(dir, 0755);
} catch (e) {
if (e.code != "EEXIST") {
throw e;
}
}
};
var copy = function (src, dest) {
var readS = fs.createReadStream(src);
var writeS = fs.createWriteStream(dest);
readS.pipe(writeS);
readS.on("end", function () {
// Operation done
});
};
var copyDir = function (src, dest) {
mkdir(dest);
var files = fs.readdirSync(src);
for (var i = 0; i < files.length; i++) {
var current = fs.lstatSync(path.join(src, files[i]));
if (current.isDirectory()) {
copyDir(path.join(src, files[i]), path.join(dest, files[i]));
} else if (current.isSymbolicLink()) {
var symlink = fs.readlinkSync(path.join(src, files[i]));
fs.symlinkSync(symlink, path.join(dest, files[i]));
} else {
copy(path.join(src, files[i]), path.join(dest, files[i]));
}
}
};
copyDir('./src', './dest');
This piece of code is inspired from https://gist.github.com/tkihira/3014700. I have made some modifications in the original code to get it working as util.pump is obsolete now.

I ended up using using copy-dir
require('copy-dir').sync(PLI.src.main.css, PLI.DIST);
If anyone has a way to do the same thing with the Node and avoiding dependencies please do tell.

DocumentDB connection in js: "require is not defined"

I've been able to create the database and query it. Using Microsoft's tutorial on using node.js to query, I have been able to accomplish this with this code:
// Simple Query
"use strict";
var documentClient = require("documentdb").DocumentClient;
var config = require("./config");
var url = require('url');
// use the previously saved config.endpoint and config.primaryKey to create a new DocumentClient
var client = new documentClient(config.endpoint, { "masterKey": config.primaryKey });
// These urls are how the DocumentDB client will find the right database and collection.
var HttpStatusCodes = { NOTFOUND: 404 };
var databaseUrl = `dbs/${config.database.id}`;
var collectionUrl = `${databaseUrl}/colls/${config.collection.id}`;
// Query JSON document collection
function queryCollection() {
console.log(`Querying collection through index:\n${config.collection.id}`);
return new Promise((resolve, reject) => {
client.queryDocuments(
collectionUrl,
'SELECT VALUE gd.NFL FROM GamblersDenDB gd WHERE gd.id = "SanDiego"'
).toArray((err, results) => {
if (err) reject(err)
else {
for (var queryResult of results) {
let resultString = JSON.stringify(queryResult);
console.log(`\tQuery returned ${resultString}`);
}
console.log();
resolve(results);
}
});
});
};
queryCollection()
Running that js file in my command prompt works! It results in the output:
C:\Users\kenv\Desktop\DocDB Test>node SimpleQuery.js
Querying collection through index:
GamblersDenColl
Query returned {"ID":"SDC","name":"Chargers"}
Great. So now I've transferred my code to my project's folder and try to run in the app with
taco run android --device
When I pull up the console, the first error that sticks out to me is
Uncaught ReferenceError: require is not defined(…)
It's pointing to the line var documentClient = require("documentdb").DocumentClient; in my code.
Here is my complete js file code that's throwing the error:
(function () {
"use strict";
document.addEventListener( 'deviceready', onDeviceReady.bind( this ), false );
function onDeviceReady() {
navigator.splashscreen.hide();
console.log("Cordova is READY!");
// Handle the Cordova pause and resume events
document.addEventListener( 'pause', onPause.bind( this ), false );
document.addEventListener( 'resume', onResume.bind( this ), false );
$(".btnURL").on("click", function(){loadURL($(this))});
function loadURL(theObj) {
cordova.InAppBrowser.open(theObj.data("url"), "_blank", "location=yes");
}
//********* jQuery VARIABLES ***************//
var $elBtnSaveName= $("#btnSaveName"),
$elShowClients= $("#btnShowClients"),
$elDivShow= $("#divShow"),
$elFormClient= $("#formClient");
//********** EVENT HANDLERS *****************//
$elShowClients.on("click", queryCollection);
//********************* DOCUMENT DB SECTION *********************************************************/
var documentClient = require("documentdb").DocumentClient;
var config = require("./config");
var url = require('url');
// use the previously saved config.endpoint and config.primaryKey to create a new DocumentClient
var client = new documentClient(config.endpoint, { "masterKey": config.primaryKey });
// These urls are how the DocumentDB client will find the right database and collection.
var HttpStatusCodes = { NOTFOUND: 404 };
var databaseUrl = `dbs/${config.database.id}`;
var collectionUrl = `${databaseUrl}/colls/${config.collection.id}`;
// Query JSON document collection
function queryCollection() {
console.log(`Querying collection through index:\n${config.collection.id}`);
return new Promise((resolve, reject) => {
client.queryDocuments(
collectionUrl,
'SELECT VALUE gd.NFL FROM GamblersDenDB gd WHERE gd.id = "SanDiego"'
).toArray((err, results) => {
if (err) reject(err)
else {
for (var queryResult of results) {
let resultString = JSON.stringify(queryResult);
console.log(`\tQuery returned ${resultString}`);
}
console.log();
resolve(results);
fnShowClientsTable(result.rows);
}
});
});
};
function fnShowClientsTable(data){
var str = "<p><table id='tableResults'";
str += "<tr><th>ID</th><th>Name</th><th class='thEmpty'> </th></tr>" //added class to <th> for formatting
for(var i = 0; i < data.length; i++) { // For X number of times worth of data...
str += "<tr><td>" + data[i].doc.ID +
"</td><td>" + data[i].doc.name +
"</td><td class='btnPencil'>✎</td></tr>";
}
str += "</table></p>"; // END table
$elDivShow.html(str); //Show string as HTML on screen
} // END fnShowClientsTable
//************************* END DOCUMENT DB SECTION ******************************************************/
}; // END onDeviceReady()
function onPause() {
// TODO: This application has been suspended. Save application state here.
};
function onResume() {
// TODO: This application has been reactivated. Restore application state here.
};
} )();
I realize my other function to push it to a string for display in HTML is probably wrong (which I will most certainly have another post about that one :)) but right now I'm trying to determine how I can get past this first error.

Programmatically stopping MongoDB

I am working on an application using Node.JS, Electron. This application will run its own instance of MongoDB. The start up of Mongo is working using the following code:
child = childProcess.exec(`mongod --dbpath ${appConfig.dbConfigPath}`);
However, when the user exits the program, I want to stop mongo. I have tried the following, all taken from MongoDB Documentation
child = childProcess.exec('mongod --shutdown');
and
child = childProcess.exec(`kill -2 ${child.pid}`);
yet neither of these are shutting down the process.
This application is being developed to run on the windows platform.
For clarity, here is my app configuration file. The init() function is executed from within my main.js. The shutdown() is executed in the windowMain.on('close').
calibration.js
'use strict';
const childProcess = require('child_process');
const fileUtils = require('./lib/utils/fileUtils');
const appConfig = require('./config/appConfig');
let child;
class Calibration {
constructor() {}
init() {
createAppConfigDir();
createAppDataDir();
startMongo();
}
shutdown() {
shutdownMongo();
}
}
function createAppConfigDir() {
fileUtils.createDirSync(appConfig.appConfigDir);
}
function createAppDataDir() {
fileUtils.createDirSync(appConfig.dbConfigPath);
}
function startMongo() {
child = childProcess.exec(`mongod --dbpath ${appConfig.dbConfigPath}`);
console.log(child.pid);
}
function shutdownMongo() {
console.log('inside shutdownMongo');
//This is where I want to shutdown Mongo
}
module.exports = new Calibration();
main.js
'use strict'
const { app, BrowserWindow, crashReporter, ipcMain: ipc } = require('electron');
const path = require('path');
const appCalibration = require('../calibration');
appCalibration.init();
const appConfig = require('../config/appConfig');
let mainWindow = null;
ipc.on('set-title', (event, title) => {
mainWindow.setTitle(title || appconfig.name);
})
ipc.on('quit', () => {
app.quit();
})
// Quit when all windows are closed.
app.on('window-all-closed', function() {
if (process.platform != 'darwin') {
app.quit();
}
});
// This method will be called when Electron has finished
// initialization and is ready to create browser windows.
app.on('ready', function() {
// Create the browser window.
mainWindow = new BrowserWindow({ center: true });
mainWindow.maximize();
mainWindow.setMinimumSize(770, 400);
mainWindow.loadURL(path.join(`file://${__dirname}`, '../ui/index.html'));
mainWindow.on('close', () => {
console.log('Inside quit')
appCalibration.shutdown();
app.quit();
});
mainWindow.on('closed', function() {
mainWindow = null;
});
});
Any assistance is greatly appreciated.

You can use Ipc to send orders through your js files.
In your main.js where you defined your electron, you can put this:
ipcMain.on("shutDownDatabase", function (event, content) {
// shutdown operations.
});
Then in some part of your application code, you can put a function like this:
function sendShutdownOrder (content){
var ipcRenderer = require("electron").ipcRenderer;
// the content can be a parameter or whatever you want that should be required for the operation.
ipcRenderer.send("shutDownDatabase", content);
}
Also I think you can use the events of Electron to shut down your db, this listens to the events of your mainWindow created when you start electron
mainWindow.on('closed', function () {
// here you command to shutdowm your data base.
mainWindow = null;
});
For more information about IPC you can see here and information about the events of your window here.

With Paulo Galdo Sandoval's suggestion, I was able to get this to work. However, I needed to get the PID for mongod from Windows Task manager. To do that I added the following function to the application configuration js file
function getTaskList() {
let pgm = 'mongod';
exec('tasklist', function(err, stdout, stderr) {
var lines = stdout.toString().split('\n');
var results = new Array();
lines.forEach(function(line) {
var parts = line.split('=');
parts.forEach(function(items) {
if (items.toString().indexOf(pgm) > -1) {
taskList.push(items.toString().replace(/\s+/g, '|').split('|')[1])
}
});
});
});
}
I also declared an array variable to place the located PID in. Then I updated my shutdown function
function shutdownMongo() {
var pgm = 'mongod';
console.log('inside shutdownMongo');
taskList.forEach(function(item) {
console.log('Killing process ' + item);
process.kill(item);
});
}
With this I am now able to start and stop Mongo as my application starts up and closes.
Thanks all

Mocha test is failing but implementation works

I am trying to write a newer watch module that uses the fs.watch method instead of the watchFile approach.
So far, it works beautifully, but only when I run it outside of mocha. I can't figure out why my unit test is throwing a tantrum, maybe someone here can?
Here is my class code:
/**
* requirements
*/
var fs, path, events;
fs = require('fs');
path = require('path');
events = require('events');
/**
* private
*/
var Monitor = function(directory, options) {
this.directory = directory;
this.options = options || {};
(this.options.lazy && this.empty()) || this.walk(this.directory);
this.watch(this.directory);
};
Monitor.prototype = new events.EventEmitter();
Monitor.prototype.watch = function(directory, stats) {
var stats = stats || {};
if (!this.directories[directory]) {
var w = fs.watch(directory, this.options, this.justlookatit.bind(this));
}
this.directories[directory] = { 'stats': stats, 'w': w };
};
Monitor.prototype.directories = function() {
if (!Object.keys(this.directories).length) {
this.walk(this.directory);
}
return this.directories;
};
Monitor.prototype.files = function() {
if (!Object.keys(this.files).length) {
this.walk(this.directory);
}
return this.files;
};
Monitor.prototype.unwatch = function() {
if (!Object.keys(this.directories).length) {
for (var dir in this.directories) {
dir.w.close();
}
}
};
Monitor.prototype.empty = function() {
this.unwatch();
this.files = {};
this.directories = {};
};
Monitor.prototype.walk = function(directory) {
var monitor = this;
this.empty();
fs.readdir(directory, function(err, files) {
if (err) return;
for (var file in files) {
var fullname = path.resolve(files[file]);
if (!monitor.options.filter || monitor.options.filter(fullname)) {
fs.stat(fullname, function(err, stats) {
if (err) return;
if (stats.isDirectory()) {
monitor.walk(fullname);
monitor.watch(fullname, stats);
} else {
monitor.files[fullname] = stats;
}
});
}
}
});
};
Monitor.prototype.justlookatit = function(action, file) {
var monitor = this;
var fullname = path.resolve(file);
if (this.options.filter && !this.options.filer(fullname)) return;
fs.exists(fullname, function(exists) {
if (exists) {
fs.stat(fullname, function(err, stats) {
if (stats.isDirectory()) {
monitor.watch(fullname, stats);
} else {
if (monitor.files[fullname]) {
if (stats.mtime.getTime() > monitor.files[fullname].mtime.getTime()) {
monitor.emit('modified', fullname, stats);
}
} else {
monitor.emit('added', fullname, stats);
}
monitor.files[fullname] = stats;
}
});
} else {
if (monitor.files[fullname]) {
delete monitor.files[fullname];
monitor.emit('deleted', fullname);
} else if (monitor.directories[fullname]) {
monitor.directories[fullname].w.close();
delete monitor.directories[fullname];
}
}
});
};
/**
* exports
*/
exports.start = function(directory, options) {
return new Monitor(directory, options);
};
Here is my Working external test code:
var watch = require("./watch.js");
var fs = require('fs');
monitor = watch.start(__dirname);
monitor.on('added', function(file, stats) {
console.log("Caught Added: " + file);
});
monitor.on('modified', function(file, stats) {
console.log("Caught Modified: " + file);
});
monitor.on('deleted', function(file) {
console.log("Caught deleted: " + file);
});
// try creating a file immediately
fs.openSync('v.md', 'w');
The first test file runs perfectly fine, and I've tried both openSync and open. Finally, here is a version of the same test code, wrapped in a mocha unit test which is timing out:
/**
* requirements
*/
var watch, Q, fs, path, mocha, chai, assert;
watch = require('../lib/watch.js');
Q = require('q');
fs = require('fs');
path = require('path');
mocha = require('mocha');
chai = require('chai');
assert = chai.assert;
/**
* variables
*/
var watch_directory = path.join(__dirname, './watch');
/**
* tests
*/
describe('test watch', function() {
it('should create a monitor and run callbacks after fs changes', function(done) {
// I had planned to implement promises that chained the three callbacks
// but couldn't get one of them working in general
var added = function(file, stats) {
console.log("added");
done();
};
var modified = function(file, stats) {
console.log("modified");
};
var deleted = function(file, stats) {
console.log("deleted");
};
// create our service
var monitor = watch.start(watch_directory);
// assert it is defined
assert.isDefined(monitor);
// establish a listener
monitor.on('added', added);
monitor.on('modified', modified);
monitor.on('deleted', deleted);
// here is a file name using the current date to prevent duplication during tests
var file = path.join(watch_directory, (new Date()).getTime() + '.md');
// let's create the file, then delete it
fs.open(file, 'w+', function(err, fileDescriptor) {
// this prints before console output from the watch.js's `justlookatit` method
console.log(err);
console.log("writing to file");
// we probably don't want to try closing the fileDescriptor if the open failed
if (err) return;
// close the file descriptor
fs.close(fileDescriptor, function() {
// delete the file we just created
// fs.unlink(file, function() { /* not a big deal */ });
});
});
// modify a known-existing test file
fs.open('test.md', 'w+', function() {/* we don't care about this */});
})
});
I checked with console.log(fullname) inside the justlookatit method on the watch code, and it spits out the correct file name, matching the one generated by the unit test.
However, it then proceeds to return false when I run fs.exists. As I undestand it, that means the file system is notifying me that a file exists before it exists, which doesn't make sense really. So I tried adding an additional delay by wrapping my fs.exists method in a setTimeout, and that didn't change the results. I have also tried using both openSync and existsSync, and that made no difference.
I'm stumped, does anyone have any ideas why the mocha code isn't working?

So, the solution was to go for a walk. I came back, looked at the code again and figured out the cause of the problem with mocha, and also identified many other bugs.
The problem was the lack of context. The justlookatit method does not have a context, and in the test.js scenario it is watching the current directory, while the mocha test is watching a sub-directory.
The path.resolve was receiving only the file name, not the directory, and therefore merged it with the default (executables) directory, so the level of test.js, or watch_test.js for mocha. It proceeded to fail to locate any of the files in the mocha test case because they were all one level below the executable.
I won't go into detail about all the other bugs, but I may come back and post the repository link when I get to a point that I want to push it online.

You're missing the callback return(done); at the end of your test. Unless you call that callback, Mocha will time out every time.

Using importsScripts within Blob in a karma environment

I am working on a small project of mine using karma, and jasmine. My targeted browser is chrome 32.
I am trying to import scripts within a web worker whom I have instanciated through a blob as follows :
describeAsyncAppliPersephone("When the application project to DOM", function()
{
it("it should call the function of DomProjection in the project associated with its event", function()
{
var eventSentBack = {
eventType: 'testReceived',
headers: { id: 14, version: 4 },
payLoad: { textChanged: 'newText' }
};
var isRendered = false;
var fnProjection = function(event, payload)
{
isRendered = true;
}
var bootstrap = [
{ eventType: 'testReceived', projection: fnProjection },
{ eventType: 'test2Received', projection: function() { } }
];
runs(function()
{
var factory = new WorkerFactory();
var worker = factory.CreateByScripts('importScripts("/base/SiteWeb/project/js/app/application.js"); var app = new application(self); app.projectOnDOM(' + JSON.stringify(eventSentBack) + '); ');
console.log(worker.WorkerLocation);
var applicationQueue = new queueAsync(worker);
var projectQueue = new queueSync(worker);
var p = new project(applicationQueue, persephoneQueue, bootstrap);
applicationQueue.publish(eventSentBack);
});
waitsFor(function() { return isRendered }, "Projection called", 500);
runs(function()
{
expect(isRendered).toBe(true);
});
});
});
workerFactory is as follows :
this.CreateByScripts = function(scripts, fDefListener, fOnError)
{
var arrayScripts = scripts;
if (!arrayScripts)
throw "unable to load worker for undefined scripts";
if (Object.prototype.toString.call(arrayScripts) !== '[object Array]')
arrayScripts = [arrayScripts];
var blob = new Blob(arrayScripts, { type: "text/javascript" });
var w = createWorker(window.URL.createObjectURL(blob));
return new QueryableWorker(w, fDefListener, fOnError);
}
where createWorker is :
createWorker = function(sUrl)
{
return new Worker(sUrl);
}
But the importScripts throws me the following error :
Uncaught SyntaxError: Failed to execute 'importScripts': the URL
'/base/SiteWeb/project/js/app/application.js' is invalid.
I have tried with the path within the browser :
http://mylocalhost:9876/base/SiteWeb/project/js/app/application.js
and it does work well.
What is the path I should use to make importScripts working successfully ?
Thanks,

You can't use relative path in worker created with Blob.
Had this problem today. Solution is explained in "The Basics of Web Workers", but a little hidden in length of the article:
The reason being: the worker (now created from a blob URL) will be resolved with a blob: prefix, while your app will be running from a different (presumably http://) scheme. Hence, the failure will be due to cross origin restrictions.
If you are determined to avoid hardcoding domain name in your workers the article has also a solution for this. Import your scripts on receiving a message with URL as one of its parameters:
self.onmessage = function(e) {
importScripts(e.data.url + 'yourscript.js');
};
and start your worker with sending that url
worker.postMessage({url: document.location.protocol + '//' + document.location.host});
The code above is simplified for clarity.