npm install posthtml-parser
Input HTML:
<a class="animals" href="#">
<span class="animals__cat" style="background: url(cat.png)">Cat</span>
</a>
Parse with posthtml-parser
:
import fs from 'fs'
import { parser } from 'posthtml-parser'
const html = fs.readFileSync('path/to/input.html', 'utf-8')
console.log(parser(html))
Resulting PostHTML AST:
[
{
tag: 'a',
attrs: {
class: 'animals',
href: '#'
},
content: [
'\n ',
{
tag: 'span',
attrs: {
class: 'animals__cat',
style: 'background: url(cat.png)'
},
content: ['Cat']
},
'\n'
]
}
]
Any parser 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. Strings represent plain text content, while objects represent HTML tags.
Tag objects generally look like this:
{
tag: 'div',
attrs: {
class: 'foo'
},
content: ['hello world!']
}
Tag objects can contain three keys:
tag
key takes the name of the tag as the value. This can include custom tags. 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. 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.directives
Type: Array
\
Default: [{name: '!doctype', start: '<', end: '>'}]
Adds processing of custom directives.
The property name
in custom directives can be of String
or RegExp
type.
xmlMode
Type: Boolean
\
Default: false
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
If set to true
, entities within the document will be decoded.
lowerCaseTags
Type: Boolean
\
Default: false
If set to true
, all tags will be lowercased. If xmlMode
is disabled.
lowerCaseAttributeNames
Type: Boolean
\
Default: false
If set to true
, all attribute names will be lowercased.
This has noticeable impact on speed.
recognizeCDATA
Type: Boolean
\
Default: false
If set to true
, CDATA sections will be recognized as text even if the xmlMode
option is not enabled.
If xmlMode
is set to true
, then CDATA sections will always be recognized as text.
recognizeSelfClosing
Type: Boolean
\
Default: false
If set to true
, self-closing tags will trigger the onclosetag
event even if xmlMode
is not set to true
.
If xmlMode
is set to true
, then self-closing tags will always be recognized.
sourceLocations
Type: Boolean
\
Default: false
If set to true
, AST nodes will have a location
property containing the start
and end
line and column position of the node.
recognizeNoValueAttribute
Type: Boolean
\
Default: false
If set to true
, AST nodes will recognize attribute with no value and mark as true
which will be correctly rendered by posthtml-render
package.