EJS
Embedded JavaScript templates
Installation
1$ npm install ejs
Features
- Control flow with
<% %> - Escaped output with
<%= %>(escape function configurable) - Unescaped raw output with
<%- %> - Newline-trim mode ('newline slurping') with
-%>ending tag - Whitespace-trim mode (slurp all whitespace) for control flow with
<%_ _%> - Custom delimiters (eg, use
<? ?>instead of<% %>) - Includes
- Client-side support
- Static caching of intermediate JavaScript
- Static caching of templates
- Complies with the Express view system
範例
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3<% if (user) { %>
<h2><%= user.name %></h2>
<% } %>
Try EJS online at: https://ionicabizau.github.io/ejs-playground/ .
Usage
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10let template = ejs.compile(str, options);
template(data);
// => Rendered HTML string
ejs.render(str, data, options);
// => Rendered HTML string
ejs.renderFile(filename, data, options, function(err, str){
// str => Rendered HTML string
});
It is also possible to use ejs.render(dataAndOptions);where you pass everything in a single object. In that case, you'll end up with local variables for all the passed options. However, be aware that your code could break breakifame add an 素name as one of your data object's properties. Therefore, we do not recommend using this shortcut.
Options
cacheCompiled functions are cached, requiresfilenamefilenameThe name of the file being rendered. Not required if you are usingrenderFile(). Used bycacheto key caches, and for includes.rootSet project root for includes with an absolute path (/file.ejs).contextFunction execution contextcompileDebugWhenfalseno debug instrumentation is compiledclientWhentrue, compiles a function that can be rendered in the browser without needing to load the EJS Runtime ( ejs.min.js ).delimiterCharacter to use with angle brackets for open/closedebugOutput generated function bodystrictWhen set totrue, generated function is in strict mode_withWhether or not to usewith() {}constructs. Iffalsethen the locals will be stored in thelocalsobject. Set tofalsein strict mode.localsNameName to use for the object storing local variables when not usingwithDefaults tolocalsrmWhitespaceRemove all safe-to-remove whitespace, including leading and trailing whitespace. It also enables a safer version of-%>line slurping for all scriptlet tags (it does not strip new lines of tags in the middle of a line) in the middleescapeThe escaping function used with<%=construct. It is used in rendering and is.toString()ed in the generation of client functions. (By default escapes XML).outputFunctionNameSet to a string (eg, 'echo' or 'print') for a function to print output inside scriptlet tags.
This project uses JSDoc . For the full public API documentation, clone the repository and run npm run doc. This will run JSDoc with the proper options and output the documentation to out/. If you want the both the public & private API documentation to . If you want the both the public & private API npm run devdoc.
Tags
<%'Scriptlet' tag, for control-flow, no output<%_'Whitespace Slurping' Scriptlet tag, strips all whitespace before it<%=Outputs the value into the template (escaped)<%-Outputs the unescaped value into the template<%#Comment tag, no execution, no output<%%Outputs a literal '<%'%%>Outputs a literal '%>'%>Plain ending tag-%>Trim-mode ('newline slurp') tag, trims following newline_%>'Whitespace Slurping' ending tag, removes all whitespace after it
For the full syntax documentation, please seedocs/syntax.md.
Includes
Includes either have to be an absolute path, or, if not, are assumed as relative to the template with the includecall. For example if you are including ./views/user/show.ejsfrom ./views/users.ejsyou would use <%- include('user/show') %>.
You must specify the filenameoption for the template with the include
call unless you are using renderFile().
You'll likely want to use the raw output tag ( <%-) with your include to avoid double-escaping the HTML output.
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5<ul>
<% users.forEach(function(user){ %>
<%- include('user/show', {user: user}) %>
<% }); %>
</ul>
Includes are inserted at runtime, so you can use variables for the path in the
includecall (for example <%- include(somePath) %>). Variables in your top-level data object are available to all your includes, down local variable down available to all your includes, down local variable down.
NOTE: Include preprocessor directives ( <% include user/show %>) are still supported.
Custom delimiters
Custom delimiters can be applied on a per-template basis, or globally:
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11let ejs = require('ejs'),
users = ['geddy', 'neil', 'alex'];
// Just one template
ejs.render('<?= users.join(" | "); ?>', {users: users}, {delimiter: '?'});
// => 'geddy | neil | alex'
// Or globally
ejs.delimiter = '$';
ejs.render('<$= users.join(" | "); $>', {users: users});
// => 'geddy | neil | alex'
Caching
EJS ships with a basic in-process cache for caching the intermediate JavaScript functions used to render templates. It's easy to plug in LRU caching using Node's lru-cachelibrary:
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3let ejs = require('ejs'),
LRU = require('lru-cache');
ejs.cache = LRU(100); // LRU cache with 100-item limit
If you want to clear the EJS cache, call ejs.clearCache. If you're using the LRU cache and need a different limit, simple reset ejs.cacheto a new instance of the LRU.
Custom file loader
The default file loader is fs.readFileSync, if you want to customize it, you can set ejs.fileLoader.
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6let ejs = require('ejs');
let myFileLoad = function (filePath) {
return 'myFileLoad: ' + fs.readFileSync(filePath);
};
ejs.fileLoader = myFileLoad;
With this feature, you can preprocess the template before reading it.
Layouts
EJS does not specifically support blocks, but layouts can be implemented by including headers and footers, like so:
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8<%- include('header') -%>
<h1>
Title
</h1>
<p>
My page
</p>
<%- include('footer') -%>
Client-side support
Go to the Latest Release , download
./ejs.jsor ./ejs.min.js. Alternately, you can compile it yourself by cloning the repository and running jake build(or $(npm bin)/jake buildif jake is not installed globally).
Include one of these files on your page, and ejsshould be available globally.
Example
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10<div id="output"></div>
<script src="ejs.min.js"></script>
<script>
let people = ['geddy', 'neil', 'alex'],
html = ejs.render('<%= people.join(", "); %>', {people: people});
// With jQuery:
$('#output').html(html);
// Vanilla JS:
document.getElementById('output').innerHTML = html;
</script>
Caveats
Most of EJS will work as expected; however, there are a few things to note:
- Obviously, since you do not have access to the filesystem,
ejs.renderFile()won't work. For the same reason,
includes do not work unless you use aninclude callback. Here is an example:1 2 3 4 5 6 7 8 9let str = "Hello <%= include('file', {person: 'John'}); %>", fn = ejs.compile(str, {client: true}); fn(data, null, function(path, d){ // include callback // path -> 'file' // d -> {person: 'John'} // Put your code here // Return the contents of file as a string }); // returns rendered string
IDE Integration with Syntax Highlighting
VSCode:Javascript EJS by DigitalBrainstem
Related projects
There are a number of implementations of EJS:
- TJ's implementation, the v1 of this library: https://github.com/tj/ejs
- Jupiter Consulting's EJS: http://www.embeddedjs.com/
- EJS Embedded JavaScript Framework on Google Code: https://code.google.com/p/embeddedjavascript/
- Sam Stephenson's Ruby implementation: https://rubygems.org/gems/ejs
- Erubis, an ERB implementation which also runs JavaScript: http://www.kuwata-lab.com/erubis/users-guide.04.html#lang-javascript
- DigitalBrainstem EJS Language support: https://github.com/Digitalbrainstem/ejs-grammar
License
Licensed under the Apache License, Version 2.0 ( http://www.apache.org/licenses/LICENSE-2.0 )
EJS Embedded JavaScript templates copyright 2112 mde@fleegix.org.
