Node Js Visual Studio

Node.js Tools for Visual Studio (NTVS) is a free, open-source plug-in that turns Visual Studio into a Node.js Integrated Development Environment (IDE). It supports a broad range of features including editing, IntelliSense, cross platform and remote debugging, edit and continue, npm integration, profiling, TypeScript, and an integrated REPL window. Tag: Node.js from Visual Studio Blog. Visual Studio Code Docker extension 1.0 – Better than Ever! Mike Morton March 16, 2020 Mar 16, 2020 03/16/20 We recently released the 1.0 version of our Visual Studio Code Docker extension, which is the first general availability (GA) release. The Docker extension makes it easier to build apps that.

-->

In this tutorial for Visual Studio development using Node.js and Express, you create a simple Node.js web application, add some code, explore some features of the IDE, and run the app.

If you haven't already installed Visual Studio, go to the Visual Studio downloads page to install it for free.

In this tutorial, you learn how to:

Create a Node.js project
Add some code
Use IntelliSense to edit code
Run the app
Hit a breakpoint in the debugger

Before you begin

Here's a quick FAQ to introduce you to some key concepts.

What is Node.js?

Node.js is a server-side JavaScript runtime environment that executes JavaScript server-side.

What is npm?

npm is the default package manager for the Node.js. The package manager makes it easier for programmers to publish and share source code of Node.js libraries and is designed to simplify installation, updating, and uninstallation of libraries.

What is express?

Express is a web application framework, used as a server framework for Node.js to build web applications. Express allows you to choose different front-end frameworks to create a UI, such as Pug (formerly called Jade). Pug is used in this tutorial.

Prerequisites

You must have Visual Studio installed and the Node.js development workload.
If you haven't already installed Visual Studio 2019, go to the Visual Studio downloads page to install it for free.
If you haven't already installed Visual Studio 2017, go to the Visual Studio downloads page to install it for free.
If you need to install the workload but already have Visual Studio, go to Tools > Get Tools and Features..., which opens the Visual Studio Installer. Choose the Node.js development workload, then choose Modify.
You must have the Node.js runtime installed.
If you don't have it installed, we recommend you install the LTS version from the Node.js website for best compatibility with outside frameworks and libraries. Node.js is built for 32-bit and 64-bit architectures. The Node.js tools in Visual Studio, included in the Node.js workload, support both versions. Only one is required and the Node.js installer only supports one being installed at a time.
In general, Visual Studio automatically detects the installed Node.js runtime. If it does not detect an installed runtime, you can configure your project to reference the installed runtime in the properties page (after you create a project, right-click the project node, choose Properties, and set the Node.exe path). You can use a global installation of Node.js or you can specify the path to a local interpreter in each of your Node.js projects.
This tutorial was tested with Node.js 8.10.0.

Create a new Node.js project

Visual Studio manages files for a single application in a project. The project includes source code, resources, and configuration files.

In this tutorial, you begin with a simple project containing code for a Node.js and express app.

Open Visual Studio.
Create a new project.
Press Esc to close the start window. Type Ctrl + Q to open the search box, type Node.js, then choose Create a new Basic Azure Node.js Express 4 application (JavaScript). In the dialog box that appears, choose Create.
From the top menu bar, choose File > New > Project. In the left pane of the New Project dialog box, expand JavaScript, then choose Node.js. In the middle pane, choose Basic Azure Node.js Express 4 application, then choose OK.
If you don't see the Basic Azure Node.js Express 4 application project template, you must add the Node.js development workload. For detailed instructions, see the Prerequisites.
Visual Studio creates the new solution and opens your project in the right pane. The app.js project file opens in the editor (left pane).
(1) Highlighted in bold is your project, using the name you gave in the New Project dialog box. In the file system, this project is represented by a .njsproj file in your project folder. You can set properties and environment variables associated with the project by right-clicking the project and choosing Properties. You can do round-tripping with other development tools, because the project file does not make custom changes to the Node.js project source.
(2) At the top level is a solution, which by default has the same name as your project. A solution, represented by a .sln file on disk, is a container for one or more related projects.
(3) The npm node shows any installed npm packages. You can right-click the npm node to search for and install npm packages using a dialog box or install and update packages using the settings in package.json and right-click options in the npm node.
(4) package.json is a file used by npm to manage package dependencies and package versions for locally-installed packages. For more information, see Manage npm packages.
(5) Project files such as app.js show up under the project node. app.js is the project startup file and that is why it shows up in bold. You can set the startup file by right-clicking a file in the project and selecting Set as Node.js startup file.
Open the npm node and make sure that all the required npm packages are present.
If any packages are missing (exclamation point icon), you can right-click the npm node and choose Install npm Packages.

Add some code

The application uses Pug for the front-end JavaScript framework. Pug uses simple markup code that compiles to HTML. (Pug is set as the view engine in app.js. The code that sets the view engine in app.js is app.set('view engine', 'pug');.)

In Solution Explorer (right pane), open the views folder, then open index.pug.
Replace the content with the following markup.
The preceding code is used to dynamically generate an HTML page with a title and welcome message. The page also includes code to display an image that changes whenever you press a button.
In the routes folder, open index.js.
Add the following code before the call to router.get:
This code creates a data object that you pass to the dynamically generated HTML page.
Replace the router.get function call with the following code:
The preceding code sets the current page using the Express router object and renders the page, passing the title and data object to the page. The index.pug file is specified here as the page to load when index.js runs. index.js is configured as the default route in app.js code (not shown).
To demonstrate several features of Visual Studio, there's a deliberate error in the line of code containing res.render. You need to fix the error before the app can run, which you do in the next section.

Use IntelliSense

IntelliSense is a Visual Studio tool that assists you as you write code.

In index.js, go to the line of code containing res.render.
Put your cursor after the data string, type : get and IntelliSense will show you the getData function defined earlier in the code. Select getData.
Add the parentheses to make it a function call, getData().
Remove the comma (,) before 'data' and you see green syntax highlighting on the expression. Hover over the syntax highlighting.
The last line of this message tells you that the JavaScript interpreter expected a comma (,).
In the lower pane, click the Error List tab and select Build + IntelliSense for the type of issues reported.
You see the warning and description along with the filename and line number.
Fix the code by adding the comma (,) before 'data'.
When corrected, line of code should look like this: res.render('index', { title: 'Express', 'data': getData() });

Set a breakpoint

You're next going to run the app with the Visual Studio debugger attached. Before doing that, you need to set a breakpoint.

In index.js, click in the left gutter before the following line of code to set a breakpoint:
res.render('index', { title: 'Express', 'data': getData() });
Breakpoints are the most basic and essential feature of reliable debugging. A breakpoint indicates where Visual Studio should suspend your running code so you can take a look at the values of variables, or the behavior of memory, or whether or not a branch of code is getting run.

Run the application

Select the debug target in the Debug toolbar, such as Web Server (Google Chrome) or Web Server (Microsoft Edge).
If Chrome is available on your machine, but does not show up as an option, choose Browse With from the debug target dropdown list, and select Chrome as the default browser target (choose Set as Default).
Press F5 (Debug > Start Debugging) to run the application.
The debugger pauses at the breakpoint you set. Now, you can inspect your app state.
Hover over getData to see its properties in a DataTip
Press F5 (Debug > Continue) to continue.
The app opens in a browser.
In the browser window, you will see 'Express' as the title and 'Welcome to Express' in the first paragraph.
Click the buttons to display different images.
Close the web browser.

(Optional) Publish to Azure App Service

In Solution Explorer, right-click the project and choose Publish.
Choose Microsoft Azure App Service.
In the App Service dialog box, you can sign into your Azure account and connect to existing Azure subscriptions.
Follow the remaining steps to select a subscription, choose or create a resource group, choose or create an app service plane, and then follow the steps when prompted to publish to Azure. For more detailed instructions, see Publish to Azure website using web deploy.
The Output window shows progress on deploying to Azure.
On successful deployment, your app opens in a browser running in Azure App Service. Click a button to display an image.

Congratulations on completing this tutorial!

Next steps

React is a popular JavaScript library developed by Facebook for building web application user interfaces. The Visual Studio Code editor supports React.js IntelliSense and code navigation out of the box.

Welcome to React

We'll be using the create-react-appgenerator for this tutorial. To use the generator as well as run the React application server, you'll need Node.js JavaScript runtime and npm (Node.js package manager) installed. npm is included with Node.js which you can download and install from Node.js downloads.

Tip: To test that you have Node.js and npm correctly installed on your machine, you can type node --version and npm --version in a terminal or command prompt.

You can now create a new React application by typing:

where my-app is the name of the folder for your application. This may take a few minutes to create the React application and install its dependencies.

Note: If you've previously installed create-react-app globally via npm install -g create-react-app, we recommend you uninstall the package using npm uninstall -g create-react-app to ensure that npx always uses the latest version.

Let's quickly run our React application by navigating to the new folder and typing npm start to start the web server and open the application in a browser:

You should see the React logo and a link to 'Learn React' on http://localhost:3000 in your browser. We'll leave the web server running while we look at the application with VS Code.

To open your React application in VS Code, open another terminal or command prompt window, navigate to the my-app folder and type code .:

Markdown preview

In the File Explorer, one file you'll see is the application README.md Markdown file. This has lots of great information about the application and React in general. A nice way to review the README is by using the VS Code Markdown Preview. You can open the preview in either the current editor group (Markdown: Open Preview⇧⌘V (Windows, Linux Ctrl+Shift+V)) or in a new editor group to the side (Markdown: Open Preview to the Side⌘K V (Windows, Linux Ctrl+K V)). You'll get nice formatting, hyperlink navigation to headers, and syntax highlighting in code blocks.

Syntax highlighting and bracket matching

Now expand the src folder and select the index.js file. You'll notice that VS Code has syntax highlighting for the various source code elements and, if you put the cursor on a parenthesis, the matching bracket is also selected.

IntelliSense

As you start typing in index.js, you'll see smart suggestions or completions.

After you select a suggestion and type ., you see the types and methods on the object through IntelliSense.

VS Code uses the TypeScript language service for its JavaScript code intelligence and it has a feature called Automatic Type Acquisition (ATA). ATA pulls down the npm Type Declaration files (*.d.ts) for the npm modules referenced in the package.json.

If you select a method, you'll also get parameter help:

Go to Definition, Peek definition

Through the TypeScript language service, VS Code can also provide type definition information in the editor through Go to Definition (F12) or Peek Definition (⌥F12 (Windows Alt+F12, Linux Ctrl+Shift+F10)). Put the cursor over the App, right click and select Peek Definition. A Peek window will open showing the App definition from App.js.

Press Escape to close the Peek window.

Hello World!

Let's update the sample application to 'Hello World!'. Create a new H1 header with 'Hello, world!' and replace the <App /> tag in ReactDOM.render with element.

Once you save the index.js file, the running instance of the server will update the web page and you'll see 'Hello World!' when you refresh your browser.

Tip: VS Code supports Auto Save, which by default saves your files after a delay. Check the Auto Save option in the File menu to turn on Auto Save or directly configure the files.autoSave user setting.

Debugging React

To debug the client side React code, we'll need to install the Debugger for Chrome extension.

Node Js Visual Studio Code

Note: This tutorial assumes you have the Chrome browser installed. There are also debugger extensions for the Edge and Firefox browsers.

Open the Extensions view (⇧⌘X (Windows, Linux Ctrl+Shift+X)) and type 'chrome' in the search box. You'll see several extensions which reference Chrome.

Press the Install button for Debugger for Chrome.

Set a breakpoint

To set a breakpoint in index.js, click on the gutter to the left of the line numbers. This will set a breakpoint which will be visible as a red circle.

Configure the Chrome debugger

We need to initially configure the debugger. To do so, go to the Run view (⇧⌘D (Windows, Linux Ctrl+Shift+D)) and click create a launch.json file to customize Run and Debug. Choose Chrome from the Select Environment dropdown list. This will create a launch.json file in a new .vscode folder in your project which includes a configuration to launch the website.

We need to make one change for our example: change the port of the url from 8080 to 3000. Your launch.json should look like this:

Ensure that your development server is running (npm start). Then press F5 or the green arrow to launch the debugger and open a new browser instance. The source code where the breakpoint is set runs on startup before the debugger was attached, so we won't hit the breakpoint until we refresh the web page. Refresh the page and you should hit your breakpoint.

You can step through your source code (F10), inspect variables such as element, and see the call stack of the client side React application.

The Debugger for Chrome extension README has lots of information on other configurations, working with sourcemaps, and troubleshooting. You can review it directly within VS Code from the Extensions view by clicking on the extension item and opening the Details view.

Live editing and debugging

If you are using webpack together with your React app, you can have a more efficient workflow by taking advantage of webpack's HMR mechanism which enables you to have live editing and debugging directly from VS Code. You can learn more in this Live edit and debug your React apps directly from VS Code blog post and the webpack Hot Module Replacement documentation.

Linting

Linters analyze your source code and can warn you about potential problems before you run your application. The JavaScript language services included with VS Code has syntax error checking support by default, which you can see in action in the Problems panel (View > Problems⇧⌘M (Windows, Linux Ctrl+Shift+M)).

Node Js Visual Studio Code Extension

Try making a small error in your React source code and you'll see a red squiggle and an error in the Problems panel.

Linters can provide more sophisticated analysis, enforcing coding conventions and detecting anti-patterns. A popular JavaScript linter is ESLint. ESLint, when combined with the ESLint VS Code extension, provides a great in-product linting experience.

First, install the ESLint command-line tool:

Then install the ESLint extension by going to the Extensions view and typing 'eslint'.

Once the ESLint extension is installed and VS Code reloaded, you'll want to create an ESLint configuration file, .eslintrc.js. You can create one using the extension's ESLint: Create ESLint configuration command from the Command Palette (⇧⌘P (Windows, Linux Ctrl+Shift+P)).

The command will prompt you to answer a series of questions in the Terminal panel. Take the defaults, and it will create a .eslintrc.js file in your project root that looks something like this:

ESLint will now analyze open files and shows a warning in index.js about 'App' being defined but never used.

You can modify the ESLint rules in the .eslintrc.js file.

Let's add an error rule for extra semi-colons:

Now when you mistakenly have multiple semicolons on a line, you'll see an error (red squiggle) in the editor and error entry in the Problems panel.

Popular Starter Kits

In this tutorial, we used the create-react-app generator to create a simple React application. There are lots of great samples and starter kits available to help build your first React application.

VS Code React Sample

This is a sample React application used for a demo at the 2016 //Build conference. The sample creates a simple TODO application and includes the source code for a Node.js Express server. It also shows how to use the Babel ES6 transpiler and then use webpack to bundle the site assets.

TypeScript React

If you're curious about TypeScript and React, you can also create a TypeScript version of the create-react-app application by specifying that you want to use the TypeScript template:

See the details at Adding TypeScript on the Create React App site.

Angular

Angular is another popular web framework. If you'd like to see an example of Angular working with VS Code, check out the Chrome Debugging with Angular CLI recipe. It will walk you through creating an Angular application and configuring the launch.json file for the Debugger for Chrome extension.

Common questions

Can I get IntelliSense within declarative JSX?

Yes. For example, if you open the create-react-app project's App.js file, you can see IntelliSense within the React JSX in the render() method.