express-hbs
v2.5.0
Published
Express handlebars template engine complete with multiple layouts, partials and blocks.
Downloads
59,760
Readme
express-hbs
Express handlebars template engine with multiple layouts, blocks and cached partials.
v2.0.0
Version 2 was a rewrite and cleanup, with no known breaking changes. Lots of bugs were fixed which may have subtly changed behaviour.
Full details: https://github.com/TryGhost/express-hbs/releases/tag/2.0.0
v1.0.0 Breaking Changes
If you're upgrading from v0.8.4 to v1.0.0 there are some potentially breaking changes to be aware of:
- Handlebars @v4.0.5 - please see the handlebars v4.0 compatibility notes
- The file extension for partial files must now match the extension configured in
extname
- please see the PR
Usage
To use with express 4.
var hbs = require('express-hbs');
// Use `.hbs` for extensions and find partials in `views/partials`.
app.engine('hbs', hbs.express4({
partialsDir: __dirname + '/views/partials'
}));
app.set('view engine', 'hbs');
app.set('views', __dirname + '/views');
To use with express 3 is the same as above, except use hbs.express3
app.engine('hbs', hbs.express3({
partialsDir: __dirname + '/views/partials'
}));
Options for #express3
and #express4
hbs.express4({
partialsDir: "{String/Array} [Required] Path to partials templates, one or several directories",
// OPTIONAL settings
restrictLayoutsTo: "{String} Absolute path to a directory to restrict layout directive reading from",
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 & partials, defaults to `.hbs`",
handlebars: "{Module} Use external handlebars instead of express-hbs dependency",
i18n: "{Object} i18n object",
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",
// override the default compile
onCompile: function(exhbs, source, filename) {
var options;
if (filename && filename.indexOf('partials') > -1) {
options = {preventIndent: true};
}
return exhbs.handlebars.compile(source, options);
}
});
Syntax
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}}
Layouts
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
⚠️ This creates a potential security vulnerability if used without a
restrictLayoutsTo
:The
restrictLayoutsTo
option will restrict reading layouts to a particular directory, if you do not pass this option then do not use thelayout
option in conjunction with passing user submitted data to res.render e.g.res.render('index', req.query)
. This allows users to read arbitrary files from your filesystem!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
layout
property: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
defaultLayout
if 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!
Helpers
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'}}}
i18n support
Express-hbs supports i18n
var i18n = require('i18n');
// minimal config
i18n.configure({
locales: ['en', 'fr'],
cookie: 'locale',
directory: __dirname + "/locales"
});
app.engine('hbs', hbs.express3({
// ... options from above
i18n: i18n, // registers __ and __n helpers
}));
app.set('view engine', 'hbs');
app.set('views', viewsDir);
// cookies are needed
app.use(express.cookieParser());
// init i18n module
app.use(i18n.init);
Engine Instances
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();
Template options
The main use case for template options is setting the handlebars "data" object - this creates global template variables accessible with an @
prefix.
Template options can be set in 3 ways. When setting global template options they can be passed as config on creation of an instance, and they can also be updated used the updateTemplateOptions(templateOptions)
method of an instance. To set template options for an individual request they can be set on res.locals
using the helper method updateLocalTemplateOptions(locals, templateOptions)
.
Both of these methods have a companion method getTemplateOptions()
and getLocalTemplateOptions(locals)
, which should be used when extending or merging the current options.
Example
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
Testing
The test suite requires the grunt-cli
package:
npm install -g grunt-cli
npm install -d
Once everything's installed, just run:
npm test
Credits
Inspiration and code from donpark/hbs
Big thanks to all CONTRIBUTORS
License
The MIT License (MIT)
Copyright (c) 2012-2023 Barc, Inc., Ghost Foundation - Released under the MIT license.