tessl/npm-parse5
HTML parser and serializer that is fully compliant with the WHATWG HTML Living Standard.
- Workspace
- tessl
- Visibility
- Public
- Created
- Last updated
- Describes
To install, run
npx @tessl/cli install tessl/npm-parse5@8.0.00
# Parse5
1
2
Parse5 is a HTML parser and serializer that provides fast, standard-compliant HTML parsing for Node.js applications. It implements the WHATWG HTML Living Standard and handles malformed HTML gracefully, making it suitable for server-side HTML processing, DOM manipulation, and web scraping applications.
3
4
## Package Information
5
6
- **Package Name**: parse5
7
- **Package Type**: npm
8
- **Language**: TypeScript
9
- **Installation**: `npm install parse5`
10
11
## Core Imports
12
13
```typescript
14
// Main parsing and serialization functions
15
import { parse, parseFragment, serialize, serializeOuter } from "parse5";
16
17
// Tree adapters and types
18
import { defaultTreeAdapter, DefaultTreeAdapterTypes } from "parse5";
19
import type { TreeAdapter, TreeAdapterTypeMap, DefaultTreeAdapterMap } from "parse5";
20
21
// Error handling
22
import { ErrorCodes, type ParserError, type ParserErrorHandler } from "parse5";
23
24
// Options interfaces
25
import type { ParserOptions, SerializerOptions } from "parse5";
26
27
// HTML constants and utilities
28
import { html, Token } from "parse5";
29
30
// Advanced tokenization (internal APIs)
31
import { Tokenizer, TokenizerMode, type TokenizerOptions, type TokenHandler } from "parse5";
32
```
33
34
For CommonJS:
35
36
```javascript
37
const {
38
parse, parseFragment, serialize, serializeOuter,
39
defaultTreeAdapter, DefaultTreeAdapterTypes,
40
ErrorCodes, html, Token,
41
Tokenizer, TokenizerMode
42
} = require("parse5");
43
```
44
45
## Basic Usage
46
47
```typescript
48
import { parse, parseFragment, serialize } from "parse5";
49
50
// Parse a complete HTML document
51
const document = parse('<!DOCTYPE html><html><head></head><body>Hello World!</body></html>');
52
53
// Parse HTML fragment
54
const fragment = parseFragment('<div><span>Content</span></div>');
55
56
// Serialize back to HTML string
57
const htmlString = serialize(document);
58
console.log(htmlString);
59
```
60
61
## Architecture
62
63
Parse5 is built around several core components:
64
65
- **Parser**: Core HTML parsing engine that converts HTML strings to AST nodes
66
- **Serializer**: Converts AST nodes back to HTML strings
67
- **Tree Adapters**: Pluggable adapters that define the structure of AST nodes
68
- **Tokenizer**: Low-level HTML tokenization engine
69
- **Location Tracking**: Optional source code location information for debugging
70
- **Error Handling**: Comprehensive parsing error detection and reporting
71
72
## Capabilities
73
74
### HTML Parsing
75
76
Core HTML parsing functionality that converts HTML strings into abstract syntax trees. Supports both complete documents and fragments with optional context.
77
78
```typescript { .api }
79
function parse<T extends TreeAdapterTypeMap = DefaultTreeAdapterMap>(
80
html: string,
81
options?: ParserOptions<T>
82
): T['document'];
83
84
function parseFragment<T extends TreeAdapterTypeMap = DefaultTreeAdapterMap>(
85
fragmentContext: T['parentNode'] | null,
86
html: string,
87
options: ParserOptions<T>
88
): T['documentFragment'];
89
90
function parseFragment<T extends TreeAdapterTypeMap = DefaultTreeAdapterMap>(
91
html: string,
92
options?: ParserOptions<T>
93
): T['documentFragment'];
94
```
95
96
[HTML Parsing](./parsing.md)
97
98
### HTML Serialization
99
100
Serialization functionality for converting parsed AST nodes back to HTML strings. Supports both inner content and complete element serialization.
101
102
```typescript { .api }
103
function serialize<T extends TreeAdapterTypeMap = DefaultTreeAdapterMap>(
104
node: T['parentNode'],
105
options?: SerializerOptions<T>
106
): string;
107
108
function serializeOuter<T extends TreeAdapterTypeMap = DefaultTreeAdapterMap>(
109
node: T['node'],
110
options?: SerializerOptions<T>
111
): string;
112
```
113
114
[HTML Serialization](./serialization.md)
115
116
### Tree Adapters
117
118
Pluggable tree adapter system that defines the structure and manipulation of AST nodes. Allows customization of how parsed HTML is represented in memory.
119
120
```typescript { .api }
121
interface TreeAdapter<T extends TreeAdapterTypeMap = TreeAdapterTypeMap> {
122
// Node creation methods
123
createDocument(): T['document'];
124
createDocumentFragment(): T['documentFragment'];
125
createElement(tagName: string, namespaceURI: string, attrs: Attribute[]): T['element'];
126
createCommentNode(data: string): T['commentNode'];
127
createTextNode(value: string): T['textNode'];
128
129
// Node manipulation methods
130
appendChild(parentNode: T['parentNode'], newNode: T['childNode']): void;
131
insertBefore(parentNode: T['parentNode'], newNode: T['childNode'], referenceNode: T['childNode']): void;
132
detachNode(node: T['childNode']): void;
133
134
// Node inspection and type guards
135
isElementNode(node: T['node']): node is T['element'];
136
isTextNode(node: T['node']): node is T['textNode'];
137
isCommentNode(node: T['node']): node is T['commentNode'];
138
isDocumentTypeNode(node: T['node']): node is T['documentType'];
139
}
140
141
const defaultTreeAdapter: TreeAdapter<DefaultTreeAdapterMap>;
142
```
143
144
[Tree Adapters](./tree-adapters.md)
145
146
### Error Handling
147
148
Comprehensive error handling system that provides detailed parsing error information with source code locations and error codes.
149
150
```typescript { .api }
151
interface ParserError {
152
code: string;
153
startLine: number;
154
startCol: number;
155
startOffset: number;
156
endLine: number;
157
endCol: number;
158
endOffset: number;
159
}
160
161
type ParserErrorHandler = (error: ParserError) => void;
162
163
enum ErrorCodes {
164
controlCharacterInInputStream = 'control-character-in-input-stream',
165
noncharacterInInputStream = 'noncharacter-in-input-stream',
166
unexpectedNullCharacter = 'unexpected-null-character',
167
unexpectedQuestionMarkInsteadOfTagName = 'unexpected-question-mark-instead-of-tag-name',
168
// ... many more error codes
169
}
170
```
171
172
[Error Handling](./error-handling.md)
173
174
### HTML Tokenization
175
176
Low-level HTML tokenization functionality for advanced use cases that require direct access to the tokenization process. Provides tokenizer class, token types, and token handlers.
177
178
```typescript { .api }
179
class Tokenizer {
180
constructor(options: TokenizerOptions, handler: TokenHandler);
181
write(chunk: string, isLastChunk: boolean): void;
182
insertHtmlAtCurrentPos(chunk: string): void;
183
}
184
185
interface TokenizerOptions {
186
sourceCodeLocationInfo?: boolean;
187
}
188
189
interface TokenHandler {
190
onComment(token: CommentToken): void;
191
onDoctype(token: DoctypeToken): void;
192
onStartTag(token: TagToken): void;
193
onEndTag(token: TagToken): void;
194
onEof(token: EOFToken): void;
195
onCharacter(token: CharacterToken): void;
196
onNullCharacter(token: CharacterToken): void;
197
onWhitespaceCharacter(token: CharacterToken): void;
198
}
199
200
const TokenizerMode: {
201
readonly DATA: State.DATA;
202
readonly RCDATA: State.RCDATA;
203
readonly RAWTEXT: State.RAWTEXT;
204
readonly SCRIPT_DATA: State.SCRIPT_DATA;
205
readonly PLAINTEXT: State.PLAINTEXT;
206
readonly CDATA_SECTION: State.CDATA_SECTION;
207
};
208
```
209
210
[HTML Tokenization](./tokenization.md)
211
212
### HTML Constants and Utilities
213
214
HTML specification constants, enumerations, and utility functions providing access to standardized HTML element names, namespace URIs, document modes, and other HTML5 specification details.
215
216
```typescript { .api }
217
namespace html {
218
enum NS {
219
HTML = 'http://www.w3.org/1999/xhtml',
220
MATHML = 'http://www.w3.org/1998/Math/MathML',
221
SVG = 'http://www.w3.org/2000/svg',
222
XLINK = 'http://www.w3.org/1999/xlink',
223
XML = 'http://www.w3.org/XML/1998/namespace',
224
XMLNS = 'http://www.w3.org/2000/xmlns/'
225
}
226
227
enum TAG_NAMES {
228
A = 'a',
229
DIV = 'div',
230
SPAN = 'span',
231
P = 'p',
232
// ... 100+ tag names
233
}
234
235
enum TAG_ID {
236
UNKNOWN = 0,
237
A = 1,
238
DIV = 27,
239
SPAN = 100,
240
// ... corresponding IDs
241
}
242
243
enum DOCUMENT_MODE {
244
NO_QUIRKS = 'no-quirks',
245
QUIRKS = 'quirks',
246
LIMITED_QUIRKS = 'limited-quirks'
247
}
248
249
enum ATTRS {
250
CLASS = 'class',
251
ID = 'id',
252
SRC = 'src',
253
HREF = 'href',
254
// ... common attributes
255
}
256
257
function getTagID(tagName: string): TAG_ID;
258
function hasUnescapedText(tagName: string, scriptingEnabled: boolean): boolean;
259
}
260
```
261
262
[HTML Constants and Utilities](./html-utilities.md)
263
264
## Core Types
265
266
```typescript { .api }
267
interface DefaultTreeAdapterMap extends TreeAdapterTypeMap<
268
Node,
269
ParentNode,
270
ChildNode,
271
Document,
272
DocumentFragment,
273
Element,
274
CommentNode,
275
TextNode,
276
Template,
277
DocumentType
278
> {}
279
280
interface ParserOptions<T extends TreeAdapterTypeMap> {
281
/** Controls noscript element parsing. Defaults to true */
282
scriptingEnabled?: boolean;
283
/** Enables source code location tracking. Defaults to false */
284
sourceCodeLocationInfo?: boolean;
285
/** Custom tree adapter for AST node structure */
286
treeAdapter?: TreeAdapter<T>;
287
/** Error handling callback */
288
onParseError?: ParserErrorHandler;
289
}
290
291
interface SerializerOptions<T extends TreeAdapterTypeMap> {
292
/** Custom tree adapter for AST node structure */
293
treeAdapter?: TreeAdapter<T>;
294
/** Controls noscript element serialization. Defaults to true */
295
scriptingEnabled?: boolean;
296
}
297
```