next
Version:
The React Framework
120 lines (119 loc) • 4.99 kB
JavaScript
import { setAttributesFromProps } from './set-attributes-from-props';
function reactElementToDOM(param) {
let { type, props } = param;
const el = document.createElement(type);
setAttributesFromProps(el, props);
const { children, dangerouslySetInnerHTML } = props;
if (dangerouslySetInnerHTML) {
el.innerHTML = dangerouslySetInnerHTML.__html || '';
} else if (children) {
el.textContent = typeof children === 'string' ? children : Array.isArray(children) ? children.join('') : '';
}
return el;
}
/**
* When a `nonce` is present on an element, browsers such as Chrome and Firefox strip it out of the
* actual HTML attributes for security reasons *when the element is added to the document*. Thus,
* given two equivalent elements that have nonces, `Element,isEqualNode()` will return false if one
* of those elements gets added to the document. Although the `element.nonce` property will be the
* same for both elements, the one that was added to the document will return an empty string for
* its nonce HTML attribute value.
*
* This custom `isEqualNode()` function therefore removes the nonce value from the `newTag` before
* comparing it to `oldTag`, restoring it afterwards.
*
* For more information, see:
* https://bugs.chromium.org/p/chromium/issues/detail?id=1211471#c12
*/ export function isEqualNode(oldTag, newTag) {
if (oldTag instanceof HTMLElement && newTag instanceof HTMLElement) {
const nonce = newTag.getAttribute('nonce');
// Only strip the nonce if `oldTag` has had it stripped. An element's nonce attribute will not
// be stripped if there is no content security policy response header that includes a nonce.
if (nonce && !oldTag.getAttribute('nonce')) {
const cloneTag = newTag.cloneNode(true);
cloneTag.setAttribute('nonce', '');
cloneTag.nonce = nonce;
return nonce === oldTag.nonce && oldTag.isEqualNode(cloneTag);
}
}
return oldTag.isEqualNode(newTag);
}
function updateElements(type, components) {
const headEl = document.querySelector('head');
if (!headEl) return;
const oldTags = new Set(headEl.querySelectorAll("" + type + "[data-next-head]"));
if (type === 'meta') {
const metaCharset = headEl.querySelector('meta[charset]');
if (metaCharset !== null) {
oldTags.add(metaCharset);
}
}
const newTags = [];
for(let i = 0; i < components.length; i++){
const component = components[i];
const newTag = reactElementToDOM(component);
newTag.setAttribute('data-next-head', '');
let isNew = true;
for (const oldTag of oldTags){
if (isEqualNode(oldTag, newTag)) {
oldTags.delete(oldTag);
isNew = false;
break;
}
}
if (isNew) {
newTags.push(newTag);
}
}
for (const oldTag of oldTags){
var _oldTag_parentNode;
(_oldTag_parentNode = oldTag.parentNode) == null ? void 0 : _oldTag_parentNode.removeChild(oldTag);
}
for (const newTag of newTags){
// meta[charset] must be first element so special case
if (newTag.tagName.toLowerCase() === 'meta' && newTag.getAttribute('charset') !== null) {
headEl.prepend(newTag);
}
headEl.appendChild(newTag);
}
}
export default function initHeadManager() {
return {
mountedInstances: new Set(),
updateHead: (head)=>{
const tags = {};
head.forEach((h)=>{
if (// If the font tag is loaded only on client navigation
// it won't be inlined. In this case revert to the original behavior
h.type === 'link' && h.props['data-optimized-fonts']) {
if (document.querySelector('style[data-href="' + h.props['data-href'] + '"]')) {
return;
} else {
h.props.href = h.props['data-href'];
h.props['data-href'] = undefined;
}
}
const components = tags[h.type] || [];
components.push(h);
tags[h.type] = components;
});
const titleComponent = tags.title ? tags.title[0] : null;
let title = '';
if (titleComponent) {
const { children } = titleComponent.props;
title = typeof children === 'string' ? children : Array.isArray(children) ? children.join('') : '';
}
if (title !== document.title) document.title = title;
[
'meta',
'base',
'link',
'style',
'script'
].forEach((type)=>{
updateElements(type, tags[type] || []);
});
}
};
}
//# sourceMappingURL=head-manager.js.map