| 1 | // Server dependencies. |
| 2 | import express, { |
| 3 | type Request as ExpressRequest, |
| 4 | type Response as ExpressResponse, |
| 5 | } from 'express'; |
| 6 | import {Readable} from 'node:stream'; |
| 7 | import type {ReadableStream as NodeReadableStream} from 'stream/web'; |
| 8 | import { |
| 9 | renderToReadableStream, |
| 10 | loadServerAction, |
| 11 | decodeReply, |
| 12 | decodeAction, |
| 13 | } from 'react-server-dom-parcel/server.edge'; |
| 14 | import {injectRSCPayload} from 'rsc-html-stream/server'; |
| 15 | |
| 16 | // Client dependencies, used for SSR. |
| 17 | // These must run in the same environment as client components (e.g. same instance of React). |
| 18 | import {createFromReadableStream} from 'react-server-dom-parcel/client.edge' with {env: 'react-client'}; |
| 19 | import {renderToReadableStream as renderHTMLToReadableStream} from 'react-dom/server.edge' with {env: 'react-client'}; |
| 20 | import ReactClient, {ReactElement} from 'react' with {env: 'react-client'}; |
| 21 | |
| 22 | // Page components. These must have "use server-entry" so they are treated as code splitting entry points. |
| 23 | import {Todos} from './Todos'; |
| 24 | |
| 25 | const app = express(); |
| 26 | |
| 27 | app.use(function (req, res, next) { |
| 28 | res.setHeader('Access-Control-Allow-Methods', 'GET,HEAD,POST'); |
| 29 | res.setHeader('Access-Control-Allow-Origin', '*'); |
| 30 | res.setHeader('Access-Control-Allow-Headers', 'rsc-action'); |
| 31 | next(); |
| 32 | }); |
| 33 | |
| 34 | app.use(express.static('dist')); |
| 35 | |
| 36 | app.get('/', async (req, res) => { |
| 37 | await render(req, res, <Todos />); |
| 38 | }); |
| 39 | |
| 40 | app.post('/', async (req, res) => { |
| 41 | await handleAction(req, res, <Todos />); |
| 42 | }); |
| 43 | |
| 44 | app.get('/todos/:id', async (req, res) => { |
| 45 | await render(req, res, <Todos id={Number(req.params.id)} />); |
| 46 | }); |
| 47 | |
| 48 | app.post('/todos/:id', async (req, res) => { |
| 49 | await handleAction(req, res, <Todos id={Number(req.params.id)} />); |
| 50 | }); |
| 51 | |
| 52 | async function render( |
| 53 | req: ExpressRequest, |
| 54 | res: ExpressResponse, |
| 55 | component: ReactElement, |
| 56 | actionResult?: any, |
| 57 | ) { |
| 58 | // Render RSC payload. |
| 59 | let root: any = component; |
| 60 | if (actionResult) { |
| 61 | root = {result: actionResult, root}; |
| 62 | } |
| 63 | let stream = renderToReadableStream(root); |
| 64 | if (req.accepts('text/html')) { |
| 65 | res.setHeader('Content-Type', 'text/html'); |
| 66 | |
| 67 | // Use client react to render the RSC payload to HTML. |
| 68 | let [s1, s2] = stream.tee(); |
| 69 | let data: Promise<ReactElement>; |
| 70 | function Content() { |
| 71 | data ??= createFromReadableStream<ReactElement>(s1); |
| 72 | return ReactClient.use(data); |
| 73 | } |
| 74 | |
| 75 | let htmlStream = await renderHTMLToReadableStream(<Content />, { |
| 76 | bootstrapScriptContent: (Todos as any).bootstrapScript, |
| 77 | }); |
| 78 | let response = htmlStream.pipeThrough(injectRSCPayload(s2)); |
| 79 | Readable.fromWeb(response as NodeReadableStream).pipe(res); |
| 80 | } else { |
| 81 | res.set('Content-Type', 'text/x-component'); |
| 82 | Readable.fromWeb(stream as NodeReadableStream).pipe(res); |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | // Handle server actions. |
| 87 | async function handleAction( |
| 88 | req: ExpressRequest, |
| 89 | res: ExpressResponse, |
| 90 | component: ReactElement, |
| 91 | ) { |
| 92 | let id = req.get('rsc-action-id'); |
| 93 | let request = new Request('http://localhost' + req.url, { |
| 94 | method: 'POST', |
| 95 | headers: req.headers as any, |
| 96 | body: Readable.toWeb(req) as ReadableStream, |
| 97 | // @ts-ignore |
| 98 | duplex: 'half', |
| 99 | }); |
| 100 | |
| 101 | if (id) { |
| 102 | let action = await loadServerAction(id); |
| 103 | let body = req.is('multipart/form-data') |
| 104 | ? await request.formData() |
| 105 | : await request.text(); |
| 106 | let args = await decodeReply<any[]>(body); |
| 107 | let result = action.apply(null, args); |
| 108 | try { |
| 109 | // Wait for any mutations |
| 110 | await result; |
| 111 | } catch (x) { |
| 112 | // We handle the error on the client |
| 113 | } |
| 114 | |
| 115 | await render(req, res, component, result); |
| 116 | } else { |
| 117 | // Form submitted by browser (progressive enhancement). |
| 118 | let formData = await request.formData(); |
| 119 | let action = await decodeAction(formData); |
| 120 | try { |
| 121 | // Wait for any mutations |
| 122 | await action(); |
| 123 | } catch (err) { |
| 124 | // TODO render error page? |
| 125 | } |
| 126 | await render(req, res, component); |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | let server = app.listen(3001); |
| 131 | console.log('Server listening on port 3001'); |
| 132 | |
| 133 | // Restart the server when it changes. |
| 134 | if (module.hot) { |
| 135 | module.hot.dispose(() => { |
| 136 | server.close(); |
| 137 | }); |
| 138 | |
| 139 | module.hot.accept(); |
| 140 | } |