ES HTML Parser
ES HTML Parser is a HTML parser that generates an abstract syntax tree similar to the ESTree specification.
This project began as a fork of hyntax and is developed to follow ESTree-like ast specification.
See online demo.
Table of Contents
Install
npm install es-html-parser
Usage
import { parse } from "es-html-parser";
const input = `
<html>
<body>
<button type="button"> press here </button>
</body>
</html>
`;
const { ast, tokens } = parse(input);
API Reference
Functions
parse
parse(html: string, options?: Options): ParseResult;
Arguments
html: HTML string to parse.options (optional)tokenAdapter: The adapter option for changing tokens information.rawContentTags(string[]) : Specifies tag names whose child contents should be treated as raw text, meaning the parser will not interpret characters like < and > as HTML syntax inside these tags.
Returns
ParseResult: Result of parsing
Types
ParseResult
interface ParseResult {
ast: DocumentNode;
tokens: AnyToken[];
}
ast: The root node of the ast.tokens: An array of resulting tokens.
AnyNode
The AnyNode is an union type of all nodes.
type AnyNode =
| DocumentNode
| TextNode
| TagNode
| OpenTagStartNode
| OpenTagEndNode
| CloseTagNode
| AttributeNode
| AttributeKeyNode
| AttributeValueNode
| AttributeValueWrapperStartNode
| AttributeValueWrapperEndNode
| ScriptTagNode
| OpenScriptTagStartNode
| CloseScriptTagNode
| OpenScriptTagEndNode
| ScriptTagContentNode
| StyleTagNode
| OpenStyleTagStartNode
| OpenStyleTagEndNode
| StyleTagContentNode
| CloseStyleTagNode
| CommentNode
| CommentOpenNode
| CommentCloseNode
| CommentContentNode
| DoctypeNode
| DoctypeOpenNode
| DoctypeCloseNode
| DoctypeAttributeNode
| DoctypeAttributeValueNode
| DoctypeAttributeWrapperStartNode
| DoctypeAttributeWrapperEndNode;
AnyToken
The AnyToken is an union type all tokens.
type AnyToken =
| Token<TokenTypes.Text>
| Token<TokenTypes.OpenTagStart>
| Token<TokenTypes.OpenTagEnd>
| Token<TokenTypes.CloseTag>
| Token<TokenTypes.AttributeKey>
| Token<TokenTypes.AttributeAssignment>
| Token<TokenTypes.AttributeValueWrapperStart>
| Token<TokenTypes.AttributeValue>
| Token<TokenTypes.AttributeValueWrapperEnd>
| Token<TokenTypes.DoctypeOpen>
| Token<TokenTypes.DoctypeAttributeValue>
| Token<TokenTypes.DoctypeAttributeWrapperStart>
| Token<TokenTypes.DoctypeAttributeWrapperEnd>
| Token<TokenTypes.DoctypeClose>
| Token<TokenTypes.CommentOpen>
| Token<TokenTypes.CommentContent>
| Token<TokenTypes.CommentClose>
| Token<TokenTypes.OpenScriptTagStart>
| Token<TokenTypes.OpenScriptTagEnd>
| Token<TokenTypes.ScriptTagContent>
| Token<TokenTypes.CloseScriptTag>
| Token<TokenTypes.OpenStyleTagStart>
| Token<TokenTypes.OpenStyleTagEnd>
| Token<TokenTypes.StyleTagContent>
| Token<TokenTypes.CloseStyleTag>;
Constants
TokenTypes
enum TokenTypes {
Text = "Text",
OpenTagStart = "OpenTagStart",
OpenTagEnd = "OpenTagEnd",
CloseTag = "CloseTag",
AttributeKey = "AttributeKey",
AttributeAssignment = "AttributeAssignment",
AttributeValueWrapperStart = "AttributeValueWrapperStart",
AttributeValue = "AttributeValue",
AttributeValueWrapperEnd = "AttributeValueWrapperEnd",
DoctypeOpen = "DoctypeOpen",
DoctypeAttributeValue = "DoctypeAttributeValue",
DoctypeAttributeWrapperStart = "DoctypeAttributeWrapperStart",
DoctypeAttributeWrapperEnd = "DoctypeAttributeWrapperEnd",
DoctypeClose = "DoctypeClose",
CommentOpen = "CommentOpen",
CommentContent = "CommentContent",
CommentClose = "CommentClose",
OpenScriptTagStart = "OpenScriptTagStart",
OpenScriptTagEnd = "OpenScriptTagEnd",
ScriptTagContent = "ScriptTagContent",
CloseScriptTag = "CloseScriptTag",
OpenStyleTagStart = "OpenStyleTagStart",
OpenStyleTagEnd = "OpenStyleTagEnd",
StyleTagContent = "StyleTagContent",
CloseStyleTag = "CloseStyleTag",
}
NodeTypes
enum NodeTypes {
Document = "Document",
Tag = "Tag",
Text = "Text",
Doctype = "Doctype",
Comment = "Comment",
CommentOpen = "CommentOpen",
CommentClose = "CommentClose",
CommentContent = "CommentContent",
Attribute = "Attribute",
AttributeKey = "AttributeKey",
AttributeValue = "AttributeValue",
AttributeValueWrapperStart = "AttributeValueWrapperStart",
AttributeValueWrapperEnd = "AttributeValueWrapperEnd",
CloseTag = "CloseTag",
OpenTagEnd = "OpenTagEnd",
OpenTagStart = "OpenTagStart",
DoctypeOpen = "DoctypeOpen",
DoctypeAttribute = "DoctypeAttribute",
DoctypeClose = "DoctypeClose",
ScriptTag = "ScriptTag",
OpenScriptTagStart = "OpenScriptTagStart",
OpenScriptTagEnd = "OpenScriptTagEnd",
ScriptTagContent = "ScriptTagContent",
StyleTag = "StyleTag",
OpenStyleTagStart = "OpenStyleTagStart",
OpenStyleTagEnd = "OpenStyleTagEnd",
StyleTagContent = "StyleTagContent",
CloseStyleTag = "CloseStyleTag",
CloseScriptTag = "CloseScriptTag",
DoctypeAttributeValue = "DoctypeAttributeValue",
DoctypeAttributeWrapperStart = "DoctypeAttributeWrapperStart",
DoctypeAttributeWrapperEnd = "DoctypeAttributeWrapperEnd",
}
AST Format
- TextNode
- TagNode
- AttributeNode
- ScriptTagNode
- StyleTagNode
- CommentNode
- DoctypeNode
- DoctypeAttributeNode
Common
BaseNode
Every AST node and token implements the BaseNode interface.
interface BaseNode {
type: string;
loc: SourceLocation;
range: [number, number];
}
The type field is representing the AST type. Its value is one of the NodeTypes or TokenTypes.
The loc and range fields represent the source location of the node.
SourceLocation
interface SourceLocation {
start: Position;
end: Position;
}
The start field represents the start location of the node.
The end field represents the end location of the node.
Position
interface Position {
line: number; // >= 1
column: number; // >= 0
}
The line field is a number representing the line number where the node positioned. (1-based index).
The column field is a number representing the offset in the line. (0-based index).
Token
All tokens implement the Token interface.
interface Token<T extends TokenTypes> extends BaseNode {
type: T;
value: string;
}
DocumentNode
DocumentNode represents a whole parsed document. It's a root node of the AST.
interface DocumentNode extends BaseNode {
type: "Document";
children: Array<TextNode | TagNode | ScriptNode | StyleNode | CommentNode>;
}
TextNode
TextNode represents any plain text in HTML.
interface TextNode extends BaseNode {
type: "Text";
value: string;
}
TagNode
TagNode represents all kinds of tag nodes in HTML except for doctype, script, style, and comment. (e.g. <div></div>, <span></span> ...)
interface TagNode extends BaseNode {
type: "Tag";
selfClosing: boolean;
name: string;
openStart: OpenTagStartNode;
openEnd: OpenTagEndNode;
close?: CloseTagNode;
children: Array<TextNode | TagNode | ScriptNode | StyleNode | CommentNode>;
attributes: Array<AttributeNode>;
}
OpenTagStartNode
OpenTagStartNode represents the opening part of the Start tags. (e.g. <div)
interface OpenTagStartNode extends BaseNode {
type: "OpenTagStart";
value: string;
}
OpenTagEndNode
OpenTagEndNode represents the closing part of the Start tags. (e.g. >, />)
interface OpenTagEndNode extends BaseNode {
type: "OpenTagEnd";
value: string;
}
CloseTagNode
ClosingTagNode represents the End tags. (e.g. </div>)
interface CloseTagNode extends BaseNode {
type: "CloseTag";
value: string;
}
AttributeNode
AttributeNode represents an attribute. (e.g. id="foo")
interface AttributeNode extends BaseNode {
type: "Attribute";
key: AttributeKeyNode;
value?: AttributeValueNode;
startWrapper?: AttributeValueWrapperStartNode;
endWrapper?: AttributeValueWrapperEndNode;
}
AttributeKeyNode
AttributeKeyNode represents a key part of an attribute. (e.g. id)
interface AttributeKeyNode extends BaseNode {
type: "AttributeKey";
value: string;
}
AttributeValueWrapperStartNode
AttributeValueWrapperStartNode represents the left side character that wraps the value of the attribute. (e.g. ", ')
interface AttributeValueWrapperStartNode extends BaseNode {
type: "AttributeValueWrapperStart";
value: string;
}
AttributeValueWrapperEndNode
AttributeValueWrapperEndNode represents the right side character that wraps the value of the attribute. (e.g. ", ')
interface AttributeValueWrapperEndNode extends BaseNode {
type: "AttributeValueWrapperEnd";
value: string;
}
AttributeValueNode
AttributeValueNode represents the value part of the attribute. It does not include wrapper characters. (e.g. foo)
interface AttributeValueNode extends BaseNode {
type: "AttributeValue";
value: string;
}
ScriptTagNode
The ScriptTagNode represents a script tags in the HTML. (e.g.<script> console.log('hello'); </script>).
interface ScriptTagNode extends BaseNode {
type: "ScriptTag";
attributes: Array<AttributeNode>;
openStart: OpenScriptTagStartNode;
openEnd: OpenScriptTagEndNode;
close: CloseScriptTagNode;
value?: ScriptTagContentNode;
}
OpenScriptTagStartNode
OpenScriptTagStartNode represents an opening part of a start script tag. (e.g. <script)
interface OpenScriptTagStartNode extends BaseNode {
type: "OpenScriptTagStart";
value: string;
}
OpenScriptTagEndNode
OpenScriptTagEndNode represents a closing part of a start script tag. (e.g. >)
interface OpenScriptTagEndNode extends BaseNode {
type: "OpenScriptTagEnd";
value: string;
}
CloseScriptTagNode
CloseScriptTagNode represents a close script tag. (e.g. </script>)
interface CloseScriptTagNode extends BaseNode {
type: "CloseScriptTag";
value: string;
}
ScriptTagContentNode
ScriptTagContentNode represents a script content in script tag. (e.g. console.log('hello');)
interface ScriptTagContentNode extends BaseNode {
type: "ScriptTagContent";
value: string;
}
StyleTagNode
StyleTagNode represents style tags. (e.g. <style> .foo {} </style>)
interface StyleTagNode extends BaseNode {
type: "StyleTag";
attributes: Array<AttributeNode>;
openStart: OpenStyleTagStartNode;
openEnd: OpenStyleTagEndNode;
close: CloseStyleTagNode;
value?: StyleTagContentNode;
}
OpenStyleTagStartNode
OpenStyleTagStartNode represents an opening part of a start style tag. (e.g. <style)
interface OpenStyleTagStartNode extends BaseNode {
type: "OpenStyleTagStart";
value: string;
}
OpenStyleTagEndNode
OpenStyleTagEndNode represents a closing part of a start style tag. (e.g. >)
interface OpenStyleTagEndNode extends BaseNode {
type: "OpenStyleTagEnd";
value: string;
}
CloseStyleTagNode
CloseStyleTagNode represents a close style tag. (e.g. </style>)
interface CloseStyleTagNode extends BaseNode {
type: "CloseStyleTag";
value: string;
}
StyleTagContentNode
StyleTagContentNode represents a style content in style tag.
interface StyleTagContentNode extends BaseNode {
type: "StyleTagContent";
value: string;
}
CommentNode
CommentNode represents comment in HTML. (e.g. <!-- content -->)
interface CommentNode extends BaseNode {
type: "Comment";
open: CommentOpenNode;
close: CommentCloseNode;
value: CommentContentNode;
}
CommentOpenNode
CommentOpenNode represents comment start character sequence. (e.g. <!--)
interface CommentOpenNode extends BaseNode {
type: "CommentOpen";
value: string;
}
CommentCloseNode
CommentCloseNode represents comment end character sequence. (e.g. -->)
interface CommentCloseNode extends BaseNode {
type: "CommentClose";
value: string;
}
CommentContentNode
The CommentContentNode represents text in the comment.
interface CommentContentNode extends BaseNode {
type: "CommentContent";
value: string;
}
DoctypeNode
DoctypeNode represents the DOCTYPE in html.
interface DoctypeNode extends BaseNode {
type: "Doctype";
attributes: Array<DoctypeAttributeNode>;
open: DoctypeOpenNode;
close: DoctypeCloseNode;
}
DoctypeOpenNode
DoctypeOpenNode represents character sequence of doctype start . (<!DOCTYPE)
interface DoctypeOpenNode extends BaseNode {
type: "DoctypeOpen";
value: string;
}
DoctypeCloseNode
DoctypeCloseNode represents the doctype end character sequence (e.g. >)
interface DoctypeCloseNode extends BaseNode {
type: "DoctypeClose";
value: string;
}
DoctypeAttributeNode
DoctypeAttributeNode represents an attribute of doctype node. (e.g. html, "-//W3C//DTD HTML 4.01 Transitional//EN")
interface DoctypeAttributeNode extends BaseNode {
type: "DoctypeAttribute";
key: DoctypeAttributeKey;
}
DoctypeAttributeValueNode
DoctypeAttributeValueNode represents a value of doctype node's attribute. (e.g. html, -//W3C//DTD HTML 4.01 Transitional//EN)
. It does not include wrapper characters (', ")
interface DoctypeAttributeValueNode extends BaseNode {
type: "DoctypeAttributeValue";
value: string;
}
DoctypeAttributeWrapperStartNode
DoctypeAttributeWrapperStartNode represents a left side character that wraps the value of the attribute. (e.g. ", ')
interface DoctypeAttributeWrapperStartNode extends BaseNode {
type: "DoctypeAttributeWrapperStart";
value: string;
}
DoctypeAttributeWrapperEndNode
DoctypeAttributeWrapperEndNode represents a right side character that wraps the value of the attribute. (e.g. ", ')
interface DoctypeAttributeWrapperEndNode extends BaseNode {
type: "DoctypeAttributeWrapperEnd";
value: string;
}