Tutorial: Full-stack JavaScript for the Enterprise. Getting started with: Ext JS, Node.js, Express, MongoDB and Docker. (5)

Posted on in Docker Environment Ext JS 6 MongoDB Node JS NoSQL

This is part V of the tutorial, and covers how the Ext JS client app can consume the server Node.js API

Let the Ext JS app consume your API

By now we have a working back-end with Node, and a working front-end with Sencha.
Now we are ready to modify our Sencha app, so we can consume our back-end data and see it all in action!

It’s a simple client application with CRUD functionality for the Users model. With other words, we can create (POST) new users, read users and user details (GET), update existing users (PUT), and remove a user (DELETE).

I’ve added the codebase to Github, so let’s go through it, file by file. We will focus on the Classic Desktop view first, later we will create a mobile phone view.

Classic

https://github.com/savelee/docker-ext-client/blob/master/classic/src/Application.js

The application doesn’t auto create a viewport. Instead I’ve created a custom launch function, which either creates a login view (with the viewport plugin enabled), or the main interface with the viewport plugin enabled. It depends on the authorization token, if you have one on the device, it will auto login.

Take a look into the following files:

Here you can see the login panel. It’s actually a non-closable, non-draggable window, locked in the middle of the screen. The user can enter the username and password, which will be posted to the Node Express server. In case the username and password match with what’s in the database, it will return a token. In the success callback, we will save the token to the browser local storage.

Notice that we created two ViewControllers. One which will be shared by the classic and modern view. (This one contains the functionality to communicate with the back-end, since that’s view irrelevant.) The other ViewController, extends from the shared VC. This is the VC that contains an alias, and is bound to the classic view.

Note that although we Bcrypt the passwords in the database. It’s not secure to send passwords over HTTP. An attacker could very easily sniff the username and password that will be in the POST. Therefore enter: https://letsencrypt.org/. You could very easily create a free SSL certificate. You can find a guide here: https://letsencrypt.org/getting-started/ so you could set this up in no time.
It’s actually very easy, as long as you have console access to your webserver.

Let's dive further into our Ext JS code:

That’s the main viewport. It’s pretty much the same as the generated one from Sencha Cmd. We’ve just added a logout button. (which will destroy the main viewport, and remove the token from the localstorage.)

This is just a view with a grid. It shows a grid column for the first_name, last_name, email and an action column to remove the user from the grid. The functionality for this can be found in:

onRemove makes an AJAX call with the DELETE method, it makes a call to a URL that contains a user id.

When you click on a row in the grid, it will open a popup window, which contains the form.
I’ve implemented a renderConfig, which will hold the selected record. That way, as soon as the window will be created, and you run setRecord() on the form, it will run updateRecord() and load the record in the form, since the model fields map the form fields.

When you submit the form, you will get into the beforeSubmit() method. Here we just determine if the form contains a hidden form field, which contains the user URL. If it does, it means, the form contains data, so every change made will be a PUT request. If the form is empty, we will add a new user, and therefore we POST to the /users overview URL. The AJAX request itself, can be found in the shared user VC.

And that’s it for the desktop view.

desktop

Modern

The mobile view re-uses most of the functionality that’s already there. What is new, are the mobile (phone) views:

If there’s a token available, it will add the main view to the viewport, else it adds a login view.

The login view is a container, which centers a login form in the middle of the screen.
It calls the login view controller, for the onLogin() method. This method uses the doLogin() method from the shared login view controller, which contains the AJAX POST call, to request a token. Once logged in, it will add the token to the local storage, and it will remove the login view from the viewport, and instead add the main view to the viewport.

The main view is just a tabpanel, with for now, just one tab. It contains a hidden back button, which will be enabled once you are in a form. And it contains a logout button, which calls the onLogout() method, which removes the token, and resets the views.
It contains a user tab, which has a card layout. It can switch between a grid view which list all the users, or a form, to edit one user.

This is the list view. It contains an itemTpl with the first_name, last_name, email, username and password. Once you tap an item, it slides in the userform.

This form contains also a toolbar with a Delete button. This toolbar will be hidden, when you open the form via the Add button. But when you tap an item, it’s visible, and the form will be prefilled with data. It contains similar functionality as in the classic toolkit. It holds a config with the record.
updateRecord() will be called, every time when you run setRecord().

Feel free to download the code base and play around with it.

mobile

By the end of this part of the tutorial, you will understand how the Sencha Ext JS client can consume the Node.js server API. In the next blog posts we will focus on getting familiar with Docker.

Read the next part

https://www.leeboonstra.com/developer/tutorial-full-stack-javascript-for-the-enterprise-getting-started-with-ext-js-node-js-express-mongodb-and-docker-6/

Tutorial: Full-stack JavaScript for the Enterprise. Getting started with: Ext JS, Node.js, Express, MongoDB and Docker. (3)

Posted on in Docker MongoDB Node JS Sencha

This is part III of the tutorial, and covers how to setup a MongoDB NoSQL database.

MongoDB & Mongoose

MongoDB is a cross-platform document-oriented database, also known as a NoSQL database, This is different compared to a traditional table-based relational database like MySQL. Instead, the structure are JSON-like documents with dynamic schemas (MongoDB calls the format BSON), making the integration of data in certain types of applications easier and faster. MongoDB is developed by MongoDB Inc. and is published as free and open-source software under a combination of the GNU Affero General Public License and the Apache License.

Mongoose is a MongoDB object modeling tool designed to work in an asynchronous environment. It provides a model layer for interacting with your MongoDB collections from Node. This model layer provides a common location for implementing document validation, persistence indirection, and other logic that should be abstracted from the business layer.

Let’s integrate this with our Node back-end. Make sure you have MongoDB installed on your machine.

Create in the root of your server folder, the following file:

After that, run from the server folder the following command on the command-line:

$ npm install

This will install MongoDb, Mongoose and Nodemon, and if you don’t have Express yet, also express.

You will have to manually start MongoDB. Open a new terminal, and use the following command on the command-line:

$ mongod

We will change our server/config/express.js, to make sure bodyParser and csrf security works for posting forms.

Let’s create a couple more routes, to create a CRUD application. We need a route for creating new users (POST), a route to read one user (GET), a route to update one user (PUT) and a route to remove (DELETE) a particular user.

We will also need a register and authenticate route, which you will need to check if the username and password are correct. If so, it will return a JWT key, which you can store on your (mobile) client app.

Open server/routes.js and change to:

I’ve created another JS file (server/config/local_settings.js), which contains all sensitive information, such as passwords, secrets and keys. Now that this is a separate file, I don’t need to check in this file into my versioning system.

It contains this:

module.exports = {
  "secret": "mysecret",
  "database": "mongodb://localhost:27017/dockerextnode"
}

Next, we will replace the server/libs/user/index.js with the below piece of code. Take a look into the comments, to figure out what I am doing.

Now run the server:

$ nodemon app.js

We don’t have data in our Mongo database yet, so we will use CURL on the command-line, to get this fixed:

$ curl -H "Content-Type: application/json" -X POST  -d '{ "username": "lee", "password": "mypassword"  }' http://127.0.0.1:9000/register

Instead of Curl, you can also use Postman. There’s a Postman extension available for Google Chrome: https://chrome.google.com/webstore/detail/postman/fhbjgbiflinjbdggehcddcbncdddomop?hl=en

Choose the method: POST
With the url: http://127.0.0.1:9000/register
Select the body tab, and create 2 x-www-form-urlencoded fields: username & password, also specify the values that belong to these fields.

See screenshot:

postman

Incase you want to test if all the values were correctly added to the database, you can run MongoDB from the command-line:

$ mongo dockerextnode
> db.users.find({}, function(err, users) { console.log(users) })

Want to checkout all my code? I hosted it on Github:
https://github.com/savelee/docker-node-server

By the end of this part of the tutorial, you will have a working JavaScript server, created with Node.js and Express. The next part of this tutorial will cover the setup of a MongoDB NoSQL database.

Read the next part

https://www.leeboonstra.com/developer/tutorial-full-stack-javascript-for-the-enterprise-getting-started-with-ext-js-node-js-express-mongodb-and-docker-4/