rsnext/packages/next/shared/lib/head.tsx
Jiachi Liu 16fd15b526
Migrate head side effects to hooks (#37526)
* rewrite head side effects component in hooks
* remove mapping from element to children in head manager since they're already the children of `<Head>`

When move `SideEffect` to hooks, the effects scheduling is earlier than life cycle. We're leverage layout effects and effects at the same time, always cache the latest head updating function in head manager in layout effects, and flush them in the effects. This could help get rid of the promises delaying approach in head manager.

Co-authored-by: Shu Ding <3676859+shuding@users.noreply.github.com>
2022-06-08 11:26:57 +00:00

196 lines
5.9 KiB
TypeScript

import React, { useContext } from 'react'
import Effect from './side-effect'
import { AmpStateContext } from './amp-context'
import { HeadManagerContext } from './head-manager-context'
import { isInAmpMode } from './amp-mode'
import { warnOnce } from './utils'
type WithInAmpMode = {
inAmpMode?: boolean
}
export function defaultHead(inAmpMode = false): JSX.Element[] {
const head = [<meta charSet="utf-8" />]
if (!inAmpMode) {
head.push(<meta name="viewport" content="width=device-width" />)
}
return head
}
function onlyReactElement(
list: Array<React.ReactElement<any>>,
child: React.ReactChild
): Array<React.ReactElement<any>> {
// React children can be "string" or "number" in this case we ignore them for backwards compat
if (typeof child === 'string' || typeof child === 'number') {
return list
}
// Adds support for React.Fragment
if (child.type === React.Fragment) {
return list.concat(
React.Children.toArray(child.props.children).reduce(
(
fragmentList: Array<React.ReactElement<any>>,
fragmentChild: React.ReactChild
): Array<React.ReactElement<any>> => {
if (
typeof fragmentChild === 'string' ||
typeof fragmentChild === 'number'
) {
return fragmentList
}
return fragmentList.concat(fragmentChild)
},
[]
)
)
}
return list.concat(child)
}
const METATYPES = ['name', 'httpEquiv', 'charSet', 'itemProp']
/*
returns a function for filtering head child elements
which shouldn't be duplicated, like <title/>
Also adds support for deduplicated `key` properties
*/
function unique() {
const keys = new Set()
const tags = new Set()
const metaTypes = new Set()
const metaCategories: { [metatype: string]: Set<string> } = {}
return (h: React.ReactElement<any>) => {
let isUnique = true
let hasKey = false
if (h.key && typeof h.key !== 'number' && h.key.indexOf('$') > 0) {
hasKey = true
const key = h.key.slice(h.key.indexOf('$') + 1)
if (keys.has(key)) {
isUnique = false
} else {
keys.add(key)
}
}
// eslint-disable-next-line default-case
switch (h.type) {
case 'title':
case 'base':
if (tags.has(h.type)) {
isUnique = false
} else {
tags.add(h.type)
}
break
case 'meta':
for (let i = 0, len = METATYPES.length; i < len; i++) {
const metatype = METATYPES[i]
if (!h.props.hasOwnProperty(metatype)) continue
if (metatype === 'charSet') {
if (metaTypes.has(metatype)) {
isUnique = false
} else {
metaTypes.add(metatype)
}
} else {
const category = h.props[metatype]
const categories = metaCategories[metatype] || new Set()
if ((metatype !== 'name' || !hasKey) && categories.has(category)) {
isUnique = false
} else {
categories.add(category)
metaCategories[metatype] = categories
}
}
}
break
}
return isUnique
}
}
/**
*
* @param headChildrenElements List of children of <Head>
*/
function reduceComponents(
headChildrenElements: Array<React.ReactElement<any>>,
props: WithInAmpMode
) {
return headChildrenElements
.reduce(onlyReactElement, [])
.reverse()
.concat(defaultHead(props.inAmpMode).reverse())
.filter(unique())
.reverse()
.map((c: React.ReactElement<any>, i: number) => {
const key = c.key || i
if (
process.env.NODE_ENV !== 'development' &&
process.env.__NEXT_OPTIMIZE_FONTS &&
!props.inAmpMode
) {
if (
c.type === 'link' &&
c.props['href'] &&
// TODO(prateekbh@): Replace this with const from `constants` when the tree shaking works.
['https://fonts.googleapis.com/css', 'https://use.typekit.net/'].some(
(url) => c.props['href'].startsWith(url)
)
) {
const newProps = { ...(c.props || {}) }
newProps['data-href'] = newProps['href']
newProps['href'] = undefined
// Add this attribute to make it easy to identify optimized tags
newProps['data-optimized-fonts'] = true
return React.cloneElement(c, newProps)
}
}
if (
process.env.NODE_ENV === 'development' &&
process.env.__NEXT_REACT_ROOT
) {
// omit JSON-LD structured data snippets from the warning
if (c.type === 'script' && c.props['type'] !== 'application/ld+json') {
const srcMessage = c.props['src']
? `<script> tag with src="${c.props['src']}"`
: `inline <script>`
warnOnce(
`Do not add <script> tags using next/head (see ${srcMessage}). Use next/script instead. \nSee more info here: https://nextjs.org/docs/messages/no-script-tags-in-head-component`
)
} else if (c.type === 'link' && c.props['rel'] === 'stylesheet') {
warnOnce(
`Do not add stylesheets using next/head (see <link rel="stylesheet"> tag with href="${c.props['href']}"). Use Document instead. \nSee more info here: https://nextjs.org/docs/messages/no-stylesheets-in-head-component`
)
}
}
return React.cloneElement(c, { key })
})
}
/**
* This component injects elements to `<head>` of your page.
* To avoid duplicated `tags` in `<head>` you can use the `key` property, which will make sure every tag is only rendered once.
*/
function Head({ children }: { children: React.ReactNode }) {
const ampState = useContext(AmpStateContext)
const headManager = useContext(HeadManagerContext)
return (
<Effect
reduceComponentsToState={reduceComponents}
headManager={headManager}
inAmpMode={isInAmpMode(ampState)}
>
{children}
</Effect>
)
}
export default Head