Files
rrweb/src/snapshot.ts
2026-04-01 12:00:00 +08:00

148 lines
3.9 KiB
TypeScript

import {
serializedNode,
serializedNodeWithId,
NodeType,
attributes,
} from './types';
let _id = 1;
function genId(): number {
return _id++;
}
function resetId() {
_id = 1;
}
function getCssRulesString(s: CSSStyleSheet): string | null {
try {
const rules = s.rules || s.cssRules;
return rules
? Array.from(rules).reduce((prev, cur) => (prev += cur.cssText), '')
: null;
} catch (error) {
return null;
}
}
function serializeNode(n: Node, doc: Document): serializedNode | false {
switch (n.nodeType) {
case n.DOCUMENT_NODE:
return {
type: NodeType.Document,
childNodes: [],
};
case n.DOCUMENT_TYPE_NODE:
return {
type: NodeType.DocumentType,
name: (n as DocumentType).name,
publicId: (n as DocumentType).publicId,
systemId: (n as DocumentType).systemId,
};
case n.ELEMENT_NODE:
const tagName = (n as HTMLElement).tagName.toLowerCase();
let attributes: attributes = {};
for (const { name, value } of Array.from((n as HTMLElement).attributes)) {
attributes[name] = value;
}
// remote css
if (tagName === 'link') {
const stylesheet = Array.from(doc.styleSheets).find(s => {
return s.href === (n as HTMLLinkElement).href;
});
const cssText = getCssRulesString(stylesheet as CSSStyleSheet);
if (cssText) {
attributes = {
_cssText: cssText,
};
}
}
// form fields
if (
tagName === 'input' ||
tagName === 'textarea' ||
tagName === 'select'
) {
const value = (n as HTMLInputElement | HTMLTextAreaElement).value;
if (
attributes.type !== 'radio' &&
attributes.type !== 'checkbox' &&
value
) {
attributes.value = value;
} else if ((n as HTMLInputElement).checked) {
attributes.checked = (n as HTMLInputElement).checked;
}
}
if (tagName === 'option') {
const selectValue = (n as HTMLOptionElement).parentElement;
if (attributes.value === (selectValue as HTMLSelectElement).value) {
attributes.selected = (n as HTMLOptionElement).selected;
}
}
return {
type: NodeType.Element,
tagName,
attributes,
childNodes: [],
};
case n.TEXT_NODE:
// The parent node may not be a html element which has a tagName attribute.
// So just let it be undefined which is ok in this use case.
const parentTagName =
n.parentNode && (n.parentNode as HTMLElement).tagName;
let textContent = (n as Text).textContent;
if (parentTagName === 'SCRIPT') {
textContent = '';
}
return {
type: NodeType.Text,
textContent: textContent || '',
};
case n.CDATA_SECTION_NODE:
return {
type: NodeType.CDATA,
textContent: '',
};
case n.COMMENT_NODE:
return {
type: NodeType.Comment,
textContent: (n as Comment).textContent || '',
};
default:
return false;
}
}
function _snapshot(n: Node, doc: Document): serializedNodeWithId | null {
const _serializedNode = serializeNode(n, doc);
if (!_serializedNode) {
// TODO: dev only
console.warn(n, 'not serialized');
return null;
}
const serializedNode: serializedNodeWithId = Object.assign(_serializedNode, {
id: genId(),
});
if (
serializedNode.type === NodeType.Document ||
serializedNode.type === NodeType.Element
) {
for (const childN of Array.from(n.childNodes)) {
const serializedChildNode = _snapshot(childN, doc);
if (serializedChildNode) {
serializedNode.childNodes.push(serializedChildNode);
}
}
}
return serializedNode;
}
function snapshot(n: Document): serializedNodeWithId | null {
resetId();
return _snapshot(n, n);
}
export default snapshot;