how to use server.ts with vite+express

[SteveSuv]

I change server.js to server.ts, and change dev script from "dev": "node server.js" to "dev": "ts-node --esm server.ts", but the console throw some ts error, how do i fix?

// handle SSR requests
app.all(
  "*",
  createRequestHandler({
    build: vite
      ? () => unstable_loadViteServerBuild(vite)
      : await import("./build/index.js"),
  })
);

/usr/local/lib/node_modules/ts-node/src/index.ts:859
    return new TSError(diagnosticText, diagnosticCodes, diagnostics);
           ^
TSError: ⨯ Unable to compile TypeScript:
server.ts:34:44 - error TS2345: Argument of type 'ViteDevServer | undefined' is not assignable to parameter of type 'ViteDevServer'.
  Type 'undefined' is not assignable to type 'ViteDevServer'.

34       ? () => unstable_loadViteServerBuild(vite)
                                              ~~~~
server.ts:35:22 - error TS2307: Cannot find module './build/index.js' or its corresponding type declarations.

35       : await import("./build/index.js"),
                        ~~~~~~~~~~~~~~~~~~

    at createTSError (/usr/local/lib/node_modules/ts-node/src/index.ts:859:12)
    at reportTSError (/usr/local/lib/node_modules/ts-node/src/index.ts:863:19)
    at getOutput (/usr/local/lib/node_modules/ts-node/src/index.ts:1077:36)
    at Object.compile (/usr/local/lib/node_modules/ts-node/src/index.ts:1433:41)
    at transformSource (/usr/local/lib/node_modules/ts-node/src/esm.ts:400:37)
    at /usr/local/lib/node_modules/ts-node/src/esm.ts:278:53
    at async addShortCircuitFlag (/usr/local/lib/node_modules/ts-node/src/esm.ts:409:15)
    at async nextLoad (node:internal/modules/esm/loader:163:22)
    at async ESMLoader.load (node:internal/modules/esm/loader:603:20)
    at async ESMLoader.moduleProvider (node:internal/modules/esm/loader:457:11) {
  diagnosticCodes: [ 2345, 2307 ]
}
error Command failed with exit code 1.

[ZeldOcarina]

Try using tsx instead of ts-node. Also, make sure to use a ! to tell typescript that variable cannot be undefined.

[jrestall]

vite-node could be worth a look "dev": "vite-node server.ts". It's early days in my migration but it seems to work and it's nice that it can use the same vite config.

[Denny966]

I'm wondering why the server.js examples aren't in typescript since everything is typescript 🤔