Express 3 handlebars template engine with multiple layouts, blocks and cached partials.
Open source project from Barc, instant real-time forum on any website.
0.7 BREAKING CHANGES: The logic for layout resolution for layoutsDir, layout and declarative layouts in previous versions stepped on each other. Read Layouts section below on how layouts are resolved.
To use with express 3.
var hbs = require('express-hbs');
// Use `.hbs` for extensions and find partials in `views/partials`.
app.engine('hbs', hbs.express3({
partialsDir: __dirname + '/views/partials'
}));
app.set('view engine', 'hbs');
app.set('views', __dirname + '/views');
Options for #express3
hbs.express3({
partialsDir: "{String/Array} [Required] Path to partials templates, one or several directories",
// OPTIONAL settings
blockHelperName: "{String} Override 'block' helper name.",
contentHelperName: "{String} Override 'contentFor' helper name.",
defaultLayout: "{String} Absolute path to default layout template",
extname: "{String} Extension for templates, defaults to `.hbs`",
handlebars: "{Module} Use external handlebars instead of express-hbs dependency",
layoutsDir: "{String} Path to layout templates",
templateOptions: "{Object} options to pass to template()",
beautify: "{Boolean} whether to pretty print HTML, see github.com/einars/js-beautify .jsbeautifyrc
});
Partials may use any extension, which is better for syntax highlighting.
To mark where layout should insert page
{{{body}}}
To declare a block placeholder in layout
{{{block "pageScripts"}}}
To define block content in a page
{{#contentFor "pageScripts"}}
CONTENT HERE
{{/contentFor}}
There are three ways to use a layout, listed in precedence order
-
Declarative within a page. Use handlebars comment
{{!< LAYOUT}}Layout file resolution:
If path starts with '.' LAYOUT is relative to template Else If `layoutsDir` is set LAYOUT is relative to `layoutsDir` Else LAYOUT from path.resolve(dirname(template), LAYOUT) -
As an option to render
res.render('veggies', { title: 'My favorite veggies', veggies: veggies, layout: 'layout/veggie' });This option also allows for layout suppression (both the default layout and when specified declaratively in a page) by passing in a falsey Javascript value as the value of the
layoutproperty:res.render('veggies', { title: 'My favorite veggies', veggies: veggies, layout: null // render without using a layout template });Layout file resolution:
If path starts with '.' layout is relative to template Else If `layoutsDir` is set layout is relative to `layoutsDir` Else layout from path.resolve(viewsDir, layout) -
Lastly, use
defaultLayoutif specified in hbs configuration options.
Layouts can be nested: just include a declarative layout tag within any layout template to have its content included in the declared "parent" layout. Be aware that too much nesting can impact performances, and stay away from infinite loops!
Synchronous helpers
hbs.registerHelper('link', function(text, options) {
var attrs = [];
for(var prop in options.hash) {
attrs.push(prop + '="' + options.hash[prop] + '"');
}
return new hbs.SafeString(
"<a " + attrs.join(" ") + ">" + text + "</a>"
);
});
# in markup
{{{link 'barc.com' href='http://barc.com'}}}
Asynchronous helpers
hbs.registerAsyncHelper('readFile', function(filename, cb) {
fs.readFile(path.join(viewsDir, filename), 'utf8', function(err, content) {
cb(new hbs.SafeString(content));
});
});
# in markup
{{{readFile 'tos.txt'}}}
Create isolated engine instances with their own cache system and handlebars engine.
var hbs = require('express-hbs');
var instance1 = hbs.create();
var instance2 = hbs.create();
in File app.js
// http://expressjs.com/api.html#app.locals
app.locals({
'PROD_MODE': 'production' === app.get('env')
});
File views/layout/default.hbs
<html>
<head>
<title>{{title}}</title>
<link type="text/css" rel="stylesheet" href="/css/style.css"/>
{{{block "pageStyles"}}}
</head>
<body>
{{{body}}}
{{> scripts}}
{{#if PROD_MODE}}
{{{block 'googleAnalyticsScripts'}}}
{{/if}}
</body>
</html>
File views/index.hbs
{{!< default}}
{{#contentFor 'pageStyles'}}
<style>
.clicker {
color: blue;
};
</style>
{{/contentFor}}
<h1>{{title}}</h1>
<p class="clicker">Click me!</p>
To run example project
npm install -d
node example/app.js
The test suite requires the grunt-cli package:
npm install -g grunt-cli
npm install -d
Once everything's installed, just run:
npm test
Inspiration and code from donpark/hbs
Big thanks to all CONTRIBUTORS
The MIT License (MIT)
Copyright (c) 2012-2014 Barc, Inc.
See file LICENSE for copying permissions.