A portal to the future

Fiber release brought with it some pretty cool features but the best is yet to come!

First, let’s talk about array children, error boundaries and renderToStream.

Then, I’ll give you a sneak peak into one of the upcoming features that might change the way you build your React applications. Portals open up a lot of opportunities and traps!

Let’s explore 2 of them: reducing client bundle sizes and easier state management.

1. A portal to the future!
2. Siddharth Kshetrapal
3. sidconf
4. @siddharthkp
5. @siddharthkp javascript architect
6. @siddharthkp design, javascript, web performance
9. bit.ly/siddharthkpshow
10. i teach react bit.ly/react-training
11. co-organise react bangalore
12. i have stickers grab them right outside
13. A portal to the future!
14. is Fiber ready yet?
15. http://isfiberreadyyet.com
16. what is fiber?
17. ground-up rewrite of the diffing algorithm React 16
18. The diffing algorithm React uses to tell which parts need to be changed
19. what does this mean for us? React 16
20. what’s new? why rewrite? ooh portals!
22. 4 tiny complaints
24. <h1>Hello!</h1> <p>I'm Siddharth</p>
25. const MyComponent = () => { return ( <h1>Hello!</h1> <p>I'm Siddharth</p> ) }
27. const MyComponent = () => { return ( <h1>Hello!</h1> <p>I'm Siddharth</p> ) }
28. const MyComponent = () => { return ( <div> <h1>Hello!</h1> <p>I'm Siddharth</p> </div> ) }
29. const MyComponent = () => { return ( <tr><td>Item 1</td></tr> <tr><td>Item 2</td></tr> ) }
30. const MyComponent = () => { return ( <div> <tr><td>Item 1</td></tr> <tr><td>Item 2</td></tr> </div> ) }
32. const MyComponent = () => { return ( <div> <tr><td>Item 1</td></tr> <tr><td>Item 2</td></tr> </div> ) }
33. const MyComponent = () => { return ( [ <tr><td>Item 1</td></tr>, <tr><td>Item 2</td></tr> ] ) }
38. componentDidCatch(error, info)
39. error boundaries try/catch, but for components
40. import React from 'react' const MyComponent = () => { return ( <ErrorBoundary> <BuggyComponent /> </ErrorBoundary> ) }
41. import React from 'react' const MyComponent = () => { return ( <ErrorBoundary> <BuggyComponent /> </ErrorBoundary> ) }
42. class ErrorBoundary extends React.Component { constructor(props) { super(props) this.state = { hasError: false } } componentDidCatch(error, info) { this.setState({ hasError: true }); } render() { if (this.state.hasError) return <h1>Something broke </h1> else return {this.props.children} } }
43. class ErrorBoundary extends React.Component { constructor(props) { super(props) this.state = { hasError: false } } componentDidCatch(error, info) { this.setState({ hasError: true }); } render() { if (this.state.hasError) return <h1>Something broke </h1> else return {this.props.children} } }
44. class ErrorBoundary extends React.Component { constructor(props) { super(props) this.state = { hasError: false } } componentDidCatch(error, info) { this.setState({ hasError: true }); } render() { if (this.state.hasError) return <h1>Something broke </h1> else return {this.props.children} } }
45. class ErrorBoundary extends React.Component { constructor(props) { super(props) this.state = { hasError: false } } componentDidCatch(error, info) { this.setState({ hasError: true }); } render() { if (this.state.hasError) return <h1>Something broke </h1> else return {this.props.children} } }
48. ReactDOM.renderToString server side rendering
49. on Node 6 82ms github.com/aickin/react-16-ssr-perf
50. on Node 6 82ms 28ms github.com/aickin/react-16-ssr-perf
51. on Node 6 82ms 28ms github.com/aickin/react-16-ssr-perf 65% faster
53. import { renderToString } from 'react-dom/server' server.get('/', (req, res) => { const html = renderToString(<App />) res.end(html) })
54. import { renderToString } from 'react-dom/server' server.get('/', (req, res) => { const html = renderToString(<App />) res.end(html) })
55. import { renderToString } from 'react-dom/server' server.get('/', (req, res) => { const html = renderToString(<App />) res.end(html) })
56. import { renderToString } from 'react-dom/server' server.get('/', (req, res) => { const html = renderToString(<App />) res.end(html) })
57. ReactDOM.renderToNodeStream
58. import { renderToNodeStream } from 'react-dom/server' server.get('/', (req, res) => { renderToNodeStream(<App />) .pipe(res) .on('end', () => res.end()) })
59. import { renderToNodeStream } from 'react-dom/server' server.get('/', (req, res) => { renderToNodeStream(<App />) .pipe(res) .on('end', () => res.end()) })
60. import { renderToNodeStream } from 'react-dom/server' server.get('/', (req, res) => { renderToNodeStream(<App />) .pipe(res) .on('end', () => res.end()) })
61. import { renderToNodeStream } from 'react-dom/server' server.get('/', (req, res) => { renderToNodeStream(<App />) .pipe(res) .on('end', () => res.end()) })
63. $ npm install react@next react-dom@next
65. why rewrite?
66. better scheduling of work
67. Filter users
68. s
69. si
70. sid
71. sidd
72. siddh
73. siddha
74. siddhar
75. siddhart
76. siddharth
77. Filter users
78. Filter users
79. s
80. s
81. siddh
82. siddh
83. siddharth
84. Filter users HUMAN JAVASCRIPT DOM
85. s Filter users
86. s Filter users keydown event 's'
87. s s keydown event 's' repaint
88. s i s
89. s i s
90. s i si
91. s i d d h a r t h siddharth
92. Filter users
93. s s
94. s s render filtered list
95. s i s
96. s i s
97. s i si
98. s i d d h a r t h s
99. s i d d h a r t h siddh
100. s i d d h a r t h siddharth
101. s i d d h a r t h siddharth
102. s i d d h a r t h siddharth
103. s i d d h a r t h siddharth
104. s i d d h a r t h siddharth
105. siddh
106. siddh
107. split work at component boundaries
108. cooperative multitasking
112. /* node_modules/react-dom/cjs/react-dom.development.js /* var ReactDOMFeatureFlags = { fiberAsyncScheduling: false, useFiber: true, }
113. /* node_modules/react-dom/cjs/react-dom.development.js /* var ReactDOMFeatureFlags = { fiberAsyncScheduling: false, useFiber: true, }
114. /* node_modules/react-dom/cjs/react-dom.development.js /* var ReactDOMFeatureFlags = { fiberAsyncScheduling: true, useFiber: true, }
115. /* your code /* ReactDOM.unstable_deferredUpdates(() => { this.setState({ filteredUsers: filteredUsers }) })
116. /* your code /* ReactDOM.unstable_deferredUpdates(() => { this.setState({ filteredUsers: filteredUsers }) })
117. /* your code /* ReactDOM.unstable_deferredUpdates(() => { this.setState({ filteredUsers: filteredUsers }) }) /* this is a low priority task /*
120. PORTALS
121. ReactDOM.render(<RootComponent/>, target)
122. ReactDOM.createPortal(<Component/>, target)
123. real world problem #1
124. tomato
125. const html = ReactDOM.renderToString(<App/>)
126. const html = ReactDOM.renderToString(<App/>) res.send(` <div id="root">${html}</div> `)
127. const html = ReactDOM.renderToString(<App/>) res.send(` <div id="root">${html}</div> `)
128. const html = ReactDOM.renderToString(<App/>) res.send(` <div id="root">${html}</div> `) ReactDOM.hydrate( <App/>, document.getElementById('root') )
129. tomato
130. tomato
131. tomato
132. tomato
133. tomato dynamic dynamic
134. tomato
135. const html = ReactDOM.renderToString(<App/>) res.send(` <div id="root">${html}</div> `) ReactDOM.hydrate( <App/>, document.getElementById('root') )
136. const html = ReactDOM.renderToString(<App/>) res.send(` <div id="root">${html}</div> `) ReactDOM.hydrate( <Client/>, document.getElementById('root') )
137. tomato
138. tomato
139. const html = ReactDOM.renderToString(<App/>) res.send(` <div id="root">${html}</div> `) ReactDOM.hydrate( <Client/>, document.getElementById('root') )
140. const html = ReactDOM.renderToString(<App/>) res.send(` <div id="root">${html}</div> <div id="client-root"></div> `) ReactDOM.hydrate( <Client/>, document.getElementById('root') )
141. const html = ReactDOM.renderToString(<App/>) res.send(` <div id="root">${html}</div> <div id="client-root"></div> `) ReactDOM.hydrate( <Client/>, document.getElementById('client-root') )
142. const html = ReactDOM.renderToString(<App/>) res.send(` <div id="root">${html}</div> <div id="client-root"></div> `) ReactDOM.hydrate( <Client/>, document.getElementById('client-root') )
143. class Client extends React.Component { }
144. class Client extends React.Component { constructor() { super() } }
145. class Client extends React.Component { constructor() { super() document.getElementById('cart').innerHTML = '' } }
146. class Client extends React.Component { constructor() { super() document.getElementById('cart').innerHTML = '' } render() { } }
147. class Client extends React.Component { constructor() { super() document.getElementById('cart').innerHTML = '' } render() { return <div> </div> } }
148. class Client extends React.Component { constructor() { super() document.getElementById('cart').innerHTML = '' } render() { const cartEl = document.getElementById('cart') return <div> </div> } }
149. class Client extends React.Component { constructor() { super() document.getElementById('cart').innerHTML = '' } render() { const cartEl = document.getElementById('cart') return <div> { ReactDOM.unstable_createPortal(<Cart />, cartEl) } </div> } }
150. tomato
151. tomato
152. tomato
153. class Client extends React.Component { constructor() { super() document.getElementById('cart').innerHTML = '' } render() { const cartEl = document.getElementById('cart') return <div> { ReactDOM.unstable_createPortal(<Cart />, cartEl) } </div> } }
154. class Client extends React.Component { constructor() { super() document.getElementById('cart').innerHTML = '' document.getElementById('menu').innerHTML = '' } render() { const cartEl = document.getElementById('cart') return <div> { ReactDOM.unstable_createPortal(<Cart />, cartEl) } </div> } }
155. class Client extends React.Component { constructor() { super() document.getElementById('cart').innerHTML = '' document.getElementById('menu').innerHTML = '' } render() { const cartEl = document.getElementById('cart') return <div> { ReactDOM.unstable_createPortal(<Cart />, cartEl) } </div> } }
156. class Client extends React.Component { constructor() { super() document.getElementById('cart').innerHTML = '' document.getElementById('menu').innerHTML = '' } render() { const cartEl = document.getElementById('cart') const menuEl = document.getElementById('menu') return <div> { ReactDOM.unstable_createPortal(<Cart />, cartEl) } </div> }
157. class Client extends React.Component { constructor() { super() document.getElementById('cart').innerHTML = '' document.getElementById('menu').innerHTML = '' } render() { const cartEl = document.getElementById('cart') const menuEl = document.getElementById('menu') return <div> { ReactDOM.unstable_createPortal(<Cart />, catdEl) } { ReactDOM.unstable_createPortal(<Menu />, menuEl) } </div>
158. tomato
159. tomato
160. tomato
161. yay, performance!
162. real world problem #2
163. tomato
164. tomato
165. tomato
166. tomato
167. tomato state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ... ]} Menu.js
168. tomato Menu.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ... ]}
169. tomato Menu.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ... ]} onClick = (item) => { this.setState(...) }
170. tomato Menu.js state: { items: [ { id: 1, count: 1 }, { id: 2, count: 1 }, ... ]} onClick = (item) => { this.setState(...) }
171. tomato Menu.js state: { items: [ { id: 1, count: 2 }, { id: 2, count: 1 }, ... ]} onClick = (item) => { this.setState(...) }
172. tomato Menu.js Sidebar.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ... ]} onClick = (item) => { this.setState(...) }
173. tomato Menu.js Sidebar.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ... ]} onClick = (item) => { this.setState(...) }
174. tomato Menu.js Sidebar.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ... ]} onClick = (item) => { this.setState(...) }
175. tomato Menu.js Sidebar.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ... ]} onClick = (item) => { this.setState(...) }
176. tomato state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...]} o Sidebar.js App.js Menu.js
178. tomato state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...]} o Sidebar.js App.js Menu.js props
179. tomato state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...]} o Sidebar.js App.js Menu.js
180. tomato state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...]} o Sidebar.js Menu.js onClick = (item) => this.setState(...) App.js
181. tomato state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...]} o Sidebar.js Menu.js onClick = (item) => this.setState(...) App.js function
182. tomato state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...]} o Sidebar.js Menu.js onClick = (item) => this.setState(...) App.js
183. tomato state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...]} o Sidebar.js Menu.js onClick = (item) => this.setState(...) App.js function call
184. tomato state: { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ...]} o Sidebar.js onClick = (item) => this.setState(...) App.js Menu.js
185. tomato Sidebar.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ...]} o Sidebar.js onClick = (item) => this.setState(...) App.js Menu.js props
186. tomato Sidebar.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ...]} o Sidebar.js onClick = (item) => this.setState(...) App.js Menu.js props
188. tomato { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...] } Store Sidebar.js Menu.js
189. tomato { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...] } Store Sidebar.js Menu.js
190. tomato { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...] } Store Sidebar.js Menu.js
191. tomato { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ...] } Store Sidebar.js Menu.js dispatch('ADD_ITEM', {id: 1})
192. tomato { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ...] } Store Sidebar.js Menu.js
193. tomato { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ...] } Store Sidebar.js Menu.js
195. tomato Menu.js Sidebar.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 0 }, ... ]} onClick = (item) => { this.setState(...) }
196. tomato Menu.js Sidebar.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ... ]} onClick = (item) => { this.setState(...) }
197. tomato Menu.js Sidebar.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ... ]} onClick = (item) => { this.setState(...) } render() { // create portal }
198. tomato Menu.js Sidebar.js state: { items: [ { id: 1, count: 0 }, { id: 2, count: 1 }, ... ]} onClick = (item) => { this.setState(...) } render() { // create portal }
199. class Menu extends React.Component { constructor() { document.getElementById('cart').innerHTML = '' } onClick() {...} render() { const cartEl = document.getElementById('cart') return <div> ... { ReactDOM.unstable_createPortal( <Cart items={this.state.items} />, cartEl) } </div> }
200. class Menu extends React.Component { constructor() { document.getElementById('cart').innerHTML = '' } onClick() {...} render() { const cartEl = document.getElementById('cart') return <div> ... { ReactDOM.unstable_createPortal( <Cart items={this.state.items} />, cartEl) } </div> }
201. class Menu extends React.Component { constructor() { document.getElementById('cart').innerHTML = '' } onClick() {...} render() { const cartEl = document.getElementById('cart') return <div> ... { ReactDOM.unstable_createPortal( <Cart items={this.state.items} />, cartEl) } </div> }
202. class Menu extends React.Component { constructor() { document.getElementById('cart').innerHTML = '' } onClick() {...} render() { const cartEl = document.getElementById('cart') return <div> ... { ReactDOM.unstable_createPortal( <Cart items={this.state.items} />, cartEl) } </div> }
203. class Menu extends React.Component { constructor() { document.getElementById('cart').innerHTML = '' } onClick() {...} render() { const cartEl = document.getElementById('cart') return <div> ... { ReactDOM.unstable_createPortal( <Cart items={this.state.items} />, cartEl) } </div> }
204. tomato Menu.js Sidebar.js
205. tomato Menu.js Sidebar.js
206. tomato Menu.js Sidebar.js
207. yay state management
208. yay state management without adding an external library
209. yay state management without adding an external library or a lot of code!
210. unstable_createPortal
212. what’s new? why rewrite? ooh portals!
213. @siddharthkp DM is open, say hi!
214. @siddharthkp DM is open, say hi! bit.ly/react-training