React recently introduced an experimental profiler API. This page gives instructions on how to use this API in a production release of your app.
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React DOM automatically supports profiling in development mode for v16.5+, but since profiling adds some small additional overhead it is opt-in for production mode. This gist explains how to opt-in.
React recently introduced an experimental profiler API. After discussing this API with several teams at Facebook, one common piece of feedback was that the performance information would be more useful if it could be associated with the events that caused the application to render (e.g. button click, XHR response). Tracing these events (or "interactions") would enable more powerful tooling to be built around the timing information, capable of answering questions like "What caused this really slow commit?" or "How long does it typically take for this interaction to update the DOM?".
With version 16.4.3, React added experimental support for this tracing by way of a new NPM package, scheduler. However the public API for this package is not yet finalized and will likely change with upcoming minor releases, so it should be used with caution.
| import React from "react"; | |
| import { Location } from "@reach/router"; | |
| let scrollPositions = {}; | |
| class ManageScrollImpl extends React.Component { | |
| componentDidMount() { | |
| try { | |
| // session storage will throw for a few reasons | |
| // - user settings |
just the bare necessities of state management.
Hotlink it from https://unpkg.com/valoo.
tl;dr I built a demo illustrating what it might look like to add async rendering to Facebook's commenting interface, while ensuring it appears on the screen simultaneous to the server-rendered story.
A key benefit of async rendering is that large updates don't block the main thread; instead, the work is spread out and performed during idle periods using cooperative scheduling.
But once you make something async, you introduce the possibility that things may appear on the screen at separate times. Especially when you're dealing with multiple UI frameworks, as is often the case at Facebook.
How do we solve this with React?
STEP 2: setup docker to run react app (dev and production) configuration: https://gist.github.com/przbadu/929fc2b0d5d4cd78a5efe76d37f891b6
Because we are using Docker, we are not going to install node, npm, create-react-app
in our development machine, not even for generating create-react-app scaffold.
For this purpose I am using 2-step docker configuration:
create-react-app
| 'use strict'; | |
| const autoprefixer = require('autoprefixer'); | |
| const ExtractTextPlugin = require('extract-text-webpack-plugin'); | |
| const path = require('path'); | |
| const { | |
| CheckerPlugin, | |
| TsConfigPathsPlugin, | |
| } = require('awesome-typescript-loader'); | |
| const HappyPack = require('happypack'); |
FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.