What is ejs?
EJS, or Embedded JavaScript templating, is a templating language that lets you generate HTML markup with plain JavaScript. It is primarily used for server-side rendering of web pages, allowing developers to create HTML templates with dynamic content.
What are ejs's main functionalities?
Interpolation
EJS allows interpolation of variables into HTML. The above code will output the value of `user.name` into the template.
<%= user.name %>
Conditionals
You can use standard JavaScript conditionals to conditionally output HTML. This code checks if `user.isAdmin` is true and outputs a paragraph if it is.
<% if (user.isAdmin) { %> <p>Admin</p> <% } %>
Loops
EJS supports JavaScript loops to iterate over arrays. This code will output each `user.name` in a list item.
<% users.forEach(function(user) { %> <li><%= user.name %></li> <% }); %>
Includes
EJS allows inclusion of other templates, which is useful for reusing common parts of your website like headers and footers. This code includes the 'user/show' template and passes the `user` object to it.
<%- include('user/show', {user: user}); %>
Custom Delimiters
EJS allows you to define custom delimiters for your templates, which can be useful if you need to use '<%' or '%>' in your HTML. This code uses '%#' as a custom delimiter.
<%# users.forEach(function(user) { %> <li><%= user.name %></li> <%# }); %>
Other packages similar to ejs
pug
Pug (formerly known as Jade) is a high-performance template engine heavily influenced by Haml and implemented with JavaScript for Node.js and browsers. It offers a more terse syntax compared to EJS and is whitespace-sensitive, which can lead to cleaner templates.
handlebars
Handlebars is a simple templating language that uses a Mustache-like syntax. It is known for its logic-less templates, which means it encourages a separation of logic from the view, unlike EJS which allows JavaScript code in templates.
mustache
Mustache is a logic-less template syntax that can be used for HTML, config files, source code - anything. It works by expanding tags in a template using values provided in a hash or object. It is simpler than EJS and does not allow for direct execution of JavaScript code within the templates.
nunjucks
Nunjucks is a templating engine for JavaScript inspired by Jinja2. It is more powerful than EJS in terms of features like template inheritance and asynchronous control, but it can be more complex to use.
EJS
Embedded JavaScript templates.
Installation
$ npm install ejs
Features
- Complies with the Express view system
- Static caching of intermediate JavaScript
- Unbuffered code for conditionals etc
<% code %>
- Escapes html by default with
<%= code %>
- Unescaped buffering with
<%- code %>
Usage
ejs.compile(str, options);
// => Function
ejs.render(str, options);
// => str
Options
locals
Local variables objectcache
Compiled functions are cached, requires filename
filename
Used by cache
to key cachescontext|scope
Function execution contextdebug
Output generated function body