shopify-liquid

A feature-rich Liquid implementation for Node.js, with compliance with Jekyll and Github Pages.

Installation:

npm install --save shopify-liquid

Render from String

Parse and Render:

var Liquid = require('shopify-liquid');
var engine = Liquid();

engine.parseAndRender('{{name | capitalize}}', {name: 'alice'})
    .then(function(html){
        // html === 'Alice'
    });

Caching templates:

var tpl = engine.parse('{{name | capitalize}}');
engine.render(tpl, {name: 'alice'})
    .then(function(html){   
        // html === 'Alice'
    });

Render from File

var engine = Liquid({
    root: path.resolve(__dirname, 'views/'),  // for layouts and partials
    extname: '.liquid',
    cache: false
});
engine.renderFile("hello.liquid", {name: 'alice'})
    .then(function(html){
       // html === 'Alice'
    });
// equivalent to: 
engine.renderFile("hello", {name: 'alice'})
    .then(function(html){
       // html === 'Alice'
    });

cache default to false, extname default to .liquid, root default to "".

Strict Rendering

Undefined filters and variables will be rendered as empty string by default. Enable strict rendering to throw errors upon undefined variables/filters:

var opts = {
    strict_variables: true, 
    strict_filters: true
};
engine.parseAndRender("{{ foo }}", {}, opts).catch(function(err){
    // err.message === undefined variable: foo
});
engine.parseAndRender("{{ 'foo' | filter1 }}", {}, opts).catch(function(err){
    // err.message === undefined filter: filter1
});
// Note: the below opts also work:
// engine.render(tpl, ctx, opts)
// engine.renderFile(path, ctx, opts)

Use with Express.js

// register liquid engine
app.engine('liquid', engine.express({
    strict_variables: true,         // Default: fasle
    strict_filters: true            // Default: false
})); 
app.set('views', './views');            // specify the views directory
app.set('view engine', 'liquid');       // set to default

There's an Express demo here.

Use in Browser

Download the dist files and import into your HTML. And window.Liquid is what you want.

<html lang="en">
<head>
  <script src="dist/liquid.min.js"></script>
</head>
<body>
  <script>
    var engine = window.Liquid();
    var src = '{{ name | capitalize}}';
    var ctx = {
      name: 'welcome to Shopify Liquid'
    };
    engine.parseAndRender(src, ctx)
      .then(function(html) {
        // html === Welcome to Shopify Liquid 
      });
  </script>
</body>
</html>

There's also a demo.

Includes

// file: color.liquid
color: '{{ color }}' shape: '{{ shape }}'

// file: theme.liquid
{% assign shape = 'circle' %}
{% include 'color' %}
{% include 'color' with 'red' %}
{% include 'color', color: 'yellow', shape: 'square' %}

The output will be:

color: '' shape: 'circle'
color: 'red' shape: 'circle'
color: 'yellow' shape: 'square'

Layouts

// file: default-layout.liquid
Header
{% block content %}My default content{% endblock %}
Footer

// file: page.liquid
{% layout "default-layout" %}
{% block content %}My page content{% endblock %}

The output of page.liquid:

Header
My page content
Footer

It's possible to define multiple blocks.
block name is optional when there's only one block.

Register Filters

// Usage: {{ name | uppper }}
engine.registerFilter('upper', function(v){
  return v.toUpperCase();
});

See existing filter implementations: https://github.com/harttle/shopify-liquid/blob/master/filters.js

Register Tags

// Usage: {% upper name%}
engine.registerTag('upper', {
    parse: function(tagToken, remainTokens) {
        this.str = tagToken.args; // name
    },
    render: function(scope, hash) {
        var str = Liquid.evalValue(this.str, scope); // 'alice'
        return Promise.resolve(str.toUpperCase()); // 'Alice'
    }
});

See existing tag implementations: https://github.com/harttle/shopify-liquid/blob/master/tags/

All Tags

Documentation: https://shopify.github.io/liquid/basics/introduction/#tags

Tag	Document	Source	Test
`case/when`	Document	Source	Test
`if`	Document	Source	Test
`unless`	Document	Source	Test
`elsif/else`	Document	Source	Test
`for`	Document	Source	Test
`break`	Document	Source	Test
`continue`	Document	Source	Test
`for: limit,offset,range,reversed`	Document	Source	Test
`cycle`	Document	Source	Test
`cycle: group`	Document	Source	Test
`tablerow`	Document	Source	Test
`tablerow: cols,limit,offset,range`	Document	Source	Test
`assign`	Document	Source	Test
`capture`	Document	Source	Test
`increment`	Document	Source	Test
`decrement`	Document	Source	Test
`raw`	Document	Source	Test
`comment`	Document	Source	Test
`include`	Document	Source	Test
`layout, block`	Document	Source	Test

All Filters

Documentation: https://shopify.github.io/liquid/basics/introduction/#filters

Filter	Document	Source	Test
`abs`	Document	Source	Test
`append`	Document	Source	Test
`capitalize`	Document	Source	Test
`ceil`	Document	Source	Test
`date`	Document	Source	Test
`default`	Document	Source	Test
`divided_by`	Document	Source	Test
`downcase`	Document	Source	Test
`escape`	Document	Source	Test
`escape_once`	Document	Source	Test
`first`	Document	Source	Test
`floor`	Document	Source	Test
`join`	Document	Source	Test
`last`	Document	Source	Test
`lstrip`	Document	Source	Test
`map`	Document	Source	Test
`minus`	Document	Source	Test
`modulo`	Document	Source	Test
`newline_to_br`	Document	Source	Test
`plus`	Document	Source	Test
`prepend`	Document	Source	Test
`remove`	Document	Source	Test
`remove_first`	Document	Source	Test
`replace`	Document	Source	Test
`replace_first`	Document	Source	Test
`reverse`	Document	Source	Test
`round`	Document	Source	Test
`rstrip`	Document	Source	Test
`size`	Document	Source	Test
`slice`	Document	Source	Test
`sort`	Document	Source	Test
`split`	Document	Source	Test
`strip`	Document	Source	Test
`strip_html`	Document	Source	Test
`strip_newlines`	Document	Source	Test
`times`	Document	Source	Test
`truncate`	Document	Source	Test
`truncatewords`	Document	Source	Test
`uniq`	Document	Source	Test
`upcase`	Document	Source	Test
`url_encode`	Document	Source	Test

Operators

Documentation: https://shopify.github.io/liquid/basics/operators/

==, !=, >, <, >=, <=, or, and, contains.

killalau / shopify-liquid