Nuxt/packages/nuxt/src/app/components/nuxt-link.ts

401 lines
13 KiB
TypeScript

import type { ComputedRef, DefineComponent, InjectionKey, PropType } from 'vue'
import { computed, defineComponent, h, inject, onBeforeUnmount, onMounted, provide, ref, resolveComponent } from 'vue'
import type { RouteLocation, RouteLocationRaw } from '#vue-router'
import { hasProtocol, joinURL, parseQuery, parseURL, withTrailingSlash, withoutTrailingSlash } from 'ufo'
import { preloadRouteComponents } from '../composables/preload'
import { onNuxtReady } from '../composables/ready'
import { navigateTo, useRouter } from '../composables/router'
import { useNuxtApp, useRuntimeConfig } from '../nuxt'
import { cancelIdleCallback, requestIdleCallback } from '../compat/idle-callback'
// @ts-expect-error virtual file
import { nuxtLinkDefaults } from '#build/nuxt.config.mjs'
const firstNonUndefined = <T> (...args: (T | undefined)[]) => args.find(arg => arg !== undefined)
const DEFAULT_EXTERNAL_REL_ATTRIBUTE = 'noopener noreferrer'
const NuxtLinkDevKeySymbol: InjectionKey<boolean> = Symbol('nuxt-link-dev-key')
export type NuxtLinkOptions = {
componentName?: string
externalRelAttribute?: string | null
activeClass?: string
exactActiveClass?: string
prefetchedClass?: string
trailingSlash?: 'append' | 'remove'
}
export type NuxtLinkProps = {
// Routing
to?: RouteLocationRaw
href?: RouteLocationRaw
external?: boolean
replace?: boolean
custom?: boolean
// Attributes
target?: '_blank' | '_parent' | '_self' | '_top' | (string & {}) | null
rel?: string | null
noRel?: boolean
prefetch?: boolean
noPrefetch?: boolean
// Styling
activeClass?: string
exactActiveClass?: string
// Vue Router's `<RouterLink>` additional props
ariaCurrentValue?: string
}
/*! @__NO_SIDE_EFFECTS__ */
export function defineNuxtLink (options: NuxtLinkOptions) {
const componentName = options.componentName || 'NuxtLink'
const checkPropConflicts = (props: NuxtLinkProps, main: keyof NuxtLinkProps, sub: keyof NuxtLinkProps): void => {
if (import.meta.dev && props[main] !== undefined && props[sub] !== undefined) {
console.warn(`[${componentName}] \`${main}\` and \`${sub}\` cannot be used together. \`${sub}\` will be ignored.`)
}
}
const resolveTrailingSlashBehavior = (
to: RouteLocationRaw,
resolve: (to: RouteLocationRaw) => RouteLocation & { href?: string }
): RouteLocationRaw | RouteLocation => {
if (!to || (options.trailingSlash !== 'append' && options.trailingSlash !== 'remove')) {
return to
}
const normalizeTrailingSlash = options.trailingSlash === 'append' ? withTrailingSlash : withoutTrailingSlash
if (typeof to === 'string') {
return normalizeTrailingSlash(to, true)
}
const path = 'path' in to ? to.path : resolve(to).path
return {
...to,
name: undefined, // named routes would otherwise always override trailing slash behavior
path: normalizeTrailingSlash(path, true)
}
}
return defineComponent({
name: componentName,
props: {
// Routing
to: {
type: [String, Object] as PropType<RouteLocationRaw>,
default: undefined,
required: false
},
href: {
type: [String, Object] as PropType<RouteLocationRaw>,
default: undefined,
required: false
},
// Attributes
target: {
type: String as PropType<string>,
default: undefined,
required: false
},
rel: {
type: String as PropType<string>,
default: undefined,
required: false
},
noRel: {
type: Boolean as PropType<boolean>,
default: undefined,
required: false
},
// Prefetching
prefetch: {
type: Boolean as PropType<boolean>,
default: undefined,
required: false
},
noPrefetch: {
type: Boolean as PropType<boolean>,
default: undefined,
required: false
},
// Styling
activeClass: {
type: String as PropType<string>,
default: undefined,
required: false
},
exactActiveClass: {
type: String as PropType<string>,
default: undefined,
required: false
},
prefetchedClass: {
type: String as PropType<string>,
default: undefined,
required: false
},
// Vue Router's `<RouterLink>` additional props
replace: {
type: Boolean as PropType<boolean>,
default: undefined,
required: false
},
ariaCurrentValue: {
type: String as PropType<string>,
default: undefined,
required: false
},
// Edge cases handling
external: {
type: Boolean as PropType<boolean>,
default: undefined,
required: false
},
// Slot API
custom: {
type: Boolean as PropType<boolean>,
default: undefined,
required: false
}
},
setup (props, { slots }) {
const router = useRouter()
const config = useRuntimeConfig()
// Resolving `to` value from `to` and `href` props
const to: ComputedRef<string | RouteLocationRaw> = computed(() => {
checkPropConflicts(props, 'to', 'href')
const path = props.to || props.href || '' // Defaults to empty string (won't render any `href` attribute)
return resolveTrailingSlashBehavior(path, router.resolve)
})
// Lazily check whether to.value has a protocol
const isProtocolURL = computed(() => typeof to.value === 'string' && hasProtocol(to.value, { acceptRelative: true }))
// Resolving link type
const isExternal = computed<boolean>(() => {
// External prop is explicitly set
if (props.external) {
return true
}
// When `target` prop is set, link is external
if (props.target && props.target !== '_self') {
return true
}
// When `to` is a route object then it's an internal link
if (typeof to.value === 'object') {
return false
}
return to.value === '' || isProtocolURL.value
})
// Prefetching
const prefetched = ref(false)
const el = import.meta.server ? undefined : ref<HTMLElement | null>(null)
const elRef = import.meta.server ? undefined : (ref: any) => { el!.value = props.custom ? ref?.$el?.nextElementSibling : ref?.$el }
if (import.meta.client) {
checkPropConflicts(props, 'prefetch', 'noPrefetch')
const shouldPrefetch = props.prefetch !== false && props.noPrefetch !== true && props.target !== '_blank' && !isSlowConnection()
if (shouldPrefetch) {
const nuxtApp = useNuxtApp()
let idleId: number
let unobserve: (() => void) | null = null
onMounted(() => {
const observer = useObserver()
onNuxtReady(() => {
idleId = requestIdleCallback(() => {
if (el?.value?.tagName) {
unobserve = observer!.observe(el.value as HTMLElement, async () => {
unobserve?.()
unobserve = null
const path = typeof to.value === 'string' ? to.value : router.resolve(to.value).fullPath
await Promise.all([
nuxtApp.hooks.callHook('link:prefetch', path).catch(() => {}),
!isExternal.value && preloadRouteComponents(to.value as string, router).catch(() => {})
])
prefetched.value = true
})
}
})
})
})
onBeforeUnmount(() => {
if (idleId) { cancelIdleCallback(idleId) }
unobserve?.()
unobserve = null
})
}
}
if (import.meta.dev && import.meta.server && !props.custom) {
const isNuxtLinkChild = inject(NuxtLinkDevKeySymbol, false)
if (isNuxtLinkChild) {
console.log('[nuxt] [NuxtLink] You can\'t nest one <a> inside another <a>. This will cause a hydration error on client-side. You can pass the `custom` prop to take full control of the markup.')
} else {
provide(NuxtLinkDevKeySymbol, true)
}
}
return () => {
if (!isExternal.value) {
const routerLinkProps: Record<string, any> = {
ref: elRef,
to: to.value,
activeClass: props.activeClass || options.activeClass,
exactActiveClass: props.exactActiveClass || options.exactActiveClass,
replace: props.replace,
ariaCurrentValue: props.ariaCurrentValue,
custom: props.custom
}
// `custom` API cannot support fallthrough attributes as the slot
// may render fragment or text root nodes (#14897, #19375)
if (!props.custom) {
if (prefetched.value) {
routerLinkProps.class = props.prefetchedClass || options.prefetchedClass
}
routerLinkProps.rel = props.rel
}
// Internal link
return h(
resolveComponent('RouterLink'),
routerLinkProps,
slots.default
)
}
// Resolves `to` value if it's a route location object
// converts `""` to `null` to prevent the attribute from being added as empty (`href=""`)
const href = typeof to.value === 'object'
? router.resolve(to.value)?.href ?? null
: (to.value && !props.external && !isProtocolURL.value)
? resolveTrailingSlashBehavior(joinURL(config.app.baseURL, to.value), router.resolve) as string
: to.value || null
// Resolves `target` value
const target = props.target || null
// Resolves `rel`
checkPropConflicts(props, 'noRel', 'rel')
const rel = (props.noRel)
? null
// converts `""` to `null` to prevent the attribute from being added as empty (`rel=""`)
: firstNonUndefined<string | null>(props.rel, options.externalRelAttribute, href ? DEFAULT_EXTERNAL_REL_ATTRIBUTE : '') || null
const navigate = () => navigateTo(href, { replace: props.replace })
// https://router.vuejs.org/api/#custom
if (props.custom) {
if (!slots.default) {
return null
}
return slots.default({
href,
navigate,
get route () {
if (!href) { return undefined }
const url = parseURL(href)
return {
path: url.pathname,
fullPath: url.pathname,
get query () { return parseQuery(url.search) },
hash: url.hash,
// stub properties for compat with vue-router
params: {},
name: undefined,
matched: [],
redirectedFrom: undefined,
meta: {},
href
}
},
rel,
target,
isExternal: isExternal.value,
isActive: false,
isExactActive: false
})
}
return h('a', { ref: el, href, rel, target }, slots.default?.())
}
}
}) as unknown as DefineComponent<NuxtLinkProps>
}
export default defineNuxtLink(nuxtLinkDefaults)
// --- Prefetching utils ---
type CallbackFn = () => void
type ObserveFn = (element: Element, callback: CallbackFn) => () => void
function useObserver (): { observe: ObserveFn } | undefined {
if (import.meta.server) { return }
const nuxtApp = useNuxtApp()
if (nuxtApp._observer) {
return nuxtApp._observer
}
let observer: IntersectionObserver | null = null
const callbacks = new Map<Element, CallbackFn>()
const observe: ObserveFn = (element, callback) => {
if (!observer) {
observer = new IntersectionObserver((entries) => {
for (const entry of entries) {
const callback = callbacks.get(entry.target)
const isVisible = entry.isIntersecting || entry.intersectionRatio > 0
if (isVisible && callback) { callback() }
}
})
}
callbacks.set(element, callback)
observer.observe(element)
return () => {
callbacks.delete(element)
observer!.unobserve(element)
if (callbacks.size === 0) {
observer!.disconnect()
observer = null
}
}
}
const _observer = nuxtApp._observer = {
observe
}
return _observer
}
function isSlowConnection () {
if (import.meta.server) { return }
// https://developer.mozilla.org/en-US/docs/Web/API/Navigator/connection
const cn = (navigator as any).connection as { saveData: boolean, effectiveType: string } | null
if (cn && (cn.saveData || /2g/.test(cn.effectiveType))) { return true }
return false
}