4.3 KiB
posthtml-parser
Parse HTML/XML to PostHTML AST. More about PostHTML
Install
NPM install
$ npm install posthtml-parser
Usage
Input HTML
<a class="animals" href="#">
<span class="animals__cat" style="background: url(cat.png)">Cat</span>
</a>
import { parser } from 'posthtml-parser'
import fs from 'fs'
const html = fs.readFileSync('path/to/input.html', 'utf-8')
console.log(parser(html)) // Logs a PostHTML AST
input HTML
<a class="animals" href="#">
<span class="animals__cat" style="background: url(cat.png)">Cat</span>
</a>
Result PostHTMLTree
[{
tag: 'a',
attrs: {
class: 'animals',
href: '#'
},
content: [
'\n ',
{
tag: 'span',
attrs: {
class: 'animals__cat',
style: 'background: url(cat.png)'
},
content: ['Cat']
},
'\n'
]
}]
PostHTML AST Format
Any parser being used with PostHTML should return a standard PostHTML Abstract Syntax Tree (AST). Fortunately, this is a very easy format to produce and understand. The AST is an array that can contain strings and objects. Any strings represent plain text content to be written to the output. Any objects represent HTML tags.
Tag objects generally look something like this:
{
tag: 'div',
attrs: {
class: 'foo'
},
content: ['hello world!']
}
Tag objects can contain three keys. The tag
key takes the name of the tag as the value. This can include custom tags. The optional attrs
key takes an object with key/value pairs representing the attributes of the html tag. A boolean attribute has an empty string as its value. Finally, the optional content
key takes an array as its value, which is a PostHTML AST. In this manner, the AST is a tree that should be walked recursively.
Options
directives
Type: Array
Default: [{name: '!doctype', start: '<', end: '>'}]
Description: Adds processing of custom directives. Note: The property name
in custom directives can be String
or RegExp
type
xmlMode
Type: Boolean
Default: false
Description: Indicates whether special tags (<script>
and <style>
) should get special treatment and if "empty" tags (eg. <br>
) can have children. If false, the content of special tags will be text only. For feeds and other XML content (documents that don't consist of HTML), set this to true.
decodeEntities
Type: Boolean
Default: false
Description: If set to true, entities within the document will be decoded.
lowerCaseTags
Type: Boolean
Default: false
Description: If set to true, all tags will be lowercased. If xmlMode
is disabled.
lowerCaseAttributeNames
Type: Boolean
Default: false
Description: If set to true, all attribute names will be lowercased. This has noticeable impact on speed.
recognizeCDATA
Type: Boolean
Default: false
Description: If set to true, CDATA sections will be recognized as text even if the xmlMode
option is not enabled. NOTE: If xmlMode
is set to true
then CDATA sections will always be recognized as text.
recognizeSelfClosing
Type: Boolean
Default: false
Description: If set to true, self-closing tags will trigger the onclosetag
event even if xmlMode
is not set to true
. NOTE: If xmlMode
is set to true
then self-closing tags will always be recognized.
sourceLocations
Type: Boolean
Default: false
Description: If set to true, AST nodes will have a location
property containing the start
and end
line and column position of the node.