rsnext/packages/next/client/dev/amp-dev.js
JJ Kasper 75748caf7f
Migrate server-sent events HMR connection to WebSocket (#29903)
This replaces the server-sent events HMR connection with a WebSocket connection to prevent hitting browser connection limits, allow sending events back from the browser, and overall better performance. 

This approach sets up the the `upgrade` event listener on the server immediately when created via `next dev` and on the first request using `req.socket.server` when created via a custom server. In a follow-up PR we can push the files changed via the WebSocket as well. 

x-ref: https://github.com/vercel/next.js/issues/10061
x-ref: https://github.com/vercel/next.js/issues/8064
x-ref: https://github.com/vercel/next.js/issues/4495

## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`

## Documentation / Examples

- [ ] Make sure the linting passes
2021-10-15 07:09:54 +00:00

94 lines
2.7 KiB
JavaScript

/* globals __webpack_hash__ */
import { displayContent } from './fouc'
import initOnDemandEntries from './on-demand-entries-client'
import { addMessageListener, connectHMR } from './error-overlay/websocket'
const data = JSON.parse(document.getElementById('__NEXT_DATA__').textContent)
let { assetPrefix, page } = data
assetPrefix = assetPrefix || ''
let mostRecentHash = null
/* eslint-disable-next-line */
let curHash = __webpack_hash__
const hotUpdatePath =
assetPrefix + (assetPrefix.endsWith('/') ? '' : '/') + '_next/static/webpack/'
// Is there a newer version of this code available?
function isUpdateAvailable() {
// __webpack_hash__ is the hash of the current compilation.
// It's a global variable injected by Webpack.
/* eslint-disable-next-line */
return mostRecentHash !== __webpack_hash__
}
// Webpack disallows updates in other states.
function canApplyUpdates() {
return module.hot.status() === 'idle'
}
// This function reads code updates on the fly and hard
// reloads the page when it has changed.
async function tryApplyUpdates() {
if (!isUpdateAvailable() || !canApplyUpdates()) {
return
}
try {
const res = await fetch(
typeof __webpack_runtime_id__ !== 'undefined'
? // eslint-disable-next-line no-undef
`${hotUpdatePath}${curHash}.${__webpack_runtime_id__}.hot-update.json`
: `${hotUpdatePath}${curHash}.hot-update.json`
)
const jsonData = await res.json()
const curPage = page === '/' ? 'index' : page
// webpack 5 uses an array instead
const pageUpdated = (
Array.isArray(jsonData.c) ? jsonData.c : Object.keys(jsonData.c)
).some((mod) => {
return (
mod.indexOf(
`pages${curPage.substr(0, 1) === '/' ? curPage : `/${curPage}`}`
) !== -1 ||
mod.indexOf(
`pages${
curPage.substr(0, 1) === '/' ? curPage : `/${curPage}`
}`.replace(/\//g, '\\')
) !== -1
)
})
if (pageUpdated) {
document.location.reload(true)
} else {
curHash = mostRecentHash
}
} catch (err) {
console.error('Error occurred checking for update', err)
document.location.reload(true)
}
}
addMessageListener((event) => {
if (event.data === '\uD83D\uDC93') {
return
}
try {
const message = JSON.parse(event.data)
if (message.action === 'sync' || message.action === 'built') {
if (!message.hash) {
return
}
mostRecentHash = message.hash
tryApplyUpdates()
} else if (message.action === 'reloadPage') {
document.location.reload(true)
}
} catch (ex) {
console.warn('Invalid HMR message: ' + event.data + '\n' + ex)
}
})
connectHMR({ path: `${assetPrefix}/_next/webpack-hmr` })
displayContent()
initOnDemandEntries()