Mastering Node.js Applications with EJS Templating
When building a Node.js backend application, sending HTML responses to clients can be a daunting task. One effective way to tackle this is by leveraging template engines like EJS (Embedded JavaScript Templating). In this comprehensive guide, we’ll delve into the world of EJS templating, exploring its features, benefits, and best practices for integrating it into your Node.js applications.
Understanding Template Engines
A template engine is a software designed to combine templates with a data model to produce real HTML code. These engines handle data interpolation, providing features like partials that would be difficult to replicate by concatenating strings. EJS is one of the most popular template engines for JavaScript, known for its simplicity and flexibility.
Getting Started with EJS
EJS files are saved with the .ejs
file extension and retain the syntax of HTML while allowing data interpolation. To set up EJS in a Node.js application using Express, create a new project folder, initialize a new Node project, and install Express and EJS. Create an app.js
file and a views
folder, with subfolders for pages
and partials
.
Setting Up EJS with Express
In app.js
, set EJS as the Express app view engine using app.set('view engine', 'ejs')
. Create an index.ejs
file in the views/pages
folder and update app.js
to render the view. Run the application and visit localhost:3000
to see the rendered HTML.
Passing Data to Templates
To combine data with templates, pass a second argument to res.render
, which must be an object accessible in the EJS template file. Update app.js
and index.ejs
to pass data and display it in the template.
EJS Syntax and Logic
EJS syntax follows the pattern of <%= %>
for escaped output and <% %>
for scriptlets. Scriptlets can contain any valid JavaScript code, allowing for conditional logic and looping through data. Update app.js
and index.ejs
to demonstrate EJS syntax and logic.
Looping Through Data
Create an articles.ejs
file and update app.js
to pass an array of post objects to the template. Use a forEach
loop to render each post object as a list item.
EJS Partials
EJS partials enable code reuse across different pages. Create head.ejs
and footer.ejs
files in the views/partials
folder and update articles.ejs
to include these partials using the include
function. Pass data to partials by including them in the parent view or during the call to include
.
Best Practices and Next Steps
In this article, we’ve covered the basics of template engines, setting up EJS, and using it in Node.js applications. We’ve also explored EJS syntax, logic, and partials. To take your skills to the next level, try creating an About page that looks like the example provided. You can also check out the code for this article on GitHub.
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