nunjucks-tag

provide nunjucks base tag to make it easy to write custom tag.

Installation

  npm install nunjucks-tag --save

Usage

const Tag = require('nunjucks-tag');
class CustomTag extends Tag {
  constructor() {
    super('custom');
    this.nodeName = 'div';
  }
  render(context, attrs, body) {
    // provide your custom logic
    return super.render(context, attrs, body());
  }
}

const assert = require('assert');
const nunjucks = require('nunjucks');
const env = nunjucks.configure('/view');
const html = env.renderString('{% custom attr=someVar %}{% endcustom %}', {someVar: "test"});
assert(html, '<div attr="test"></div>');

Properties

• end: whether as a close tag, default true
• useCustomParser: whether using custom parser, default true
• nodeName: the output html element's tag name, default as tagName
• tagName: the tag name use in template

Methods

• render(context, attrs, body):String - The actual renderFn, extend it to provide custom logic
• convertAttrs(attrs):String - Convert attrs to html attribute string

Custom parser rules

• Comma between attributes is optional.
• Attribute keys should only match 1 of the following 2 patterns:
  • String ("data-key"="value" key="value")
  • Symbol with hyphen (data-key="value")
• Attributes without value must be a simple symbol or an expression

Attribute convert rules

• all the attr name && value will be escape
• single attrs
  • only allow string, will escape && ignore string with space, "disabled" someVar "some space" "<" => disabled someValue &lt;
  • number/array/object/falsely will be ignore, 123, [12,13] {a:'b'} undefined false null => nothing
• key-value attrs
  • string/number will output as escape string, attr1=123 attr2="test" attr3="<div" => attr1="123" attr2="test" attr3="&lt;div"
  • SafeString will output as what they are, attr2="<div"|safe => attr2="<div"
  • object/array will output as String(item), attr1={} attr2=["a", "b"] => attr1="[object Object] attr2="[object Array]"
  • undefined/null will ignore, attr1=undefined attr2=null => empty string