react-router@7 & vite@5 + SSL doesn't work

[iwan-uschka]

Reproduction

I simply followed the instructions at https://reactrouter.com/start/framework/installation

npx create-react-router@latest my-react-router-app
cd my-react-router-app
npm i
npm run dev

and http://localhost:5173 just works.

Installing and adding @vitejs/plugin-basic-ssl to vite.config.js like

import { reactRouter } from "@react-router/dev/vite";
import autoprefixer from "autoprefixer";
import tailwindcss from "tailwindcss";
import { defineConfig } from "vite";
import tsconfigPaths from "vite-tsconfig-paths";
import basicSsl from "@vitejs/plugin-basic-ssl";

export default defineConfig({
  css: {
    postcss: {
      plugins: [tailwindcss, autoprefixer],
    },
  },
  plugins: [reactRouter(), tsconfigPaths(), basicSsl()],
});

results in a server error when trying to open https://localhost:5173/:

npm run dev

> dev
> react-router dev

Re-optimizing dependencies because lockfile has changed
  ➜  Local:   https://localhost:5173/
  ➜  Network: use --host to expose
  ➜  press h + enter to show help
12:36:13 PM [vite] Internal server error: Headers.set: ":method" is an invalid header name.
      at Object.webidl.errors.exception (node:internal/deps/undici/undici:3564:14)
      at Object.webidl.errors.invalidArgument (node:internal/deps/undici/undici:3575:28)
      at _Headers.set (node:internal/deps/undici/undici:8814:31)
      at fromNodeHeaders (/Users/iwanuschka/projects/react-router-test/my-react-router-app/node_modules/@react-router/dev/dist/vite.js:803:17)
      at fromNodeRequest (/Users/iwanuschka/projects/react-router-test/my-react-router-app/node_modules/@react-router/dev/dist/vite.js:819:14)
      at nodeHandler (/Users/iwanuschka/projects/react-router-test/my-react-router-app/node_modules/@react-router/dev/dist/vite.js:1968:30)
      at /Users/iwanuschka/projects/react-router-test/my-react-router-app/node_modules/@react-router/dev/dist/vite.js:1975:23

---

I checked if the error occurs without React Router by following the instructions at https://vite.dev/guide/#scaffolding-your-first-vite-project

npm create vite@latest
npm create vite@latest my-react-app -- --template react

and installing and adding @vitejs/plugin-basic-ssl to vite.config.js like

import { defineConfig } from "vite";
import react from "@vitejs/plugin-react";
import basicSsl from "@vitejs/plugin-basic-ssl";

// https://vite.dev/config/
export default defineConfig({
  plugins: [react(), basicSsl()],
});

. Result: https://localhost:5173/ does work.

---

The error does not occur after adding server.proxy = {} to vite.config.js:

import { reactRouter } from "@react-router/dev/vite";
import autoprefixer from "autoprefixer";
import tailwindcss from "tailwindcss";
import { defineConfig } from "vite";
import tsconfigPaths from "vite-tsconfig-paths";
import basicSsl from "@vitejs/plugin-basic-ssl";

export default defineConfig({
  css: {
    postcss: {
      plugins: [tailwindcss, autoprefixer],
    },
  },
  server: {
    proxy: {},
  },
  plugins: [reactRouter(), tsconfigPaths(), basicSsl()],
});

According to vitejs/vite#4184 this leads to the usage of HTTP/1.1.

---

Probably related:

• Not work with Node.js v21 when using https in dev server vitejs/vite#15495 (comment)
• HTTP2 Pseudo headers get rejected by Remix [\w Vite] remix#7867

---

System Info

System:
    OS: macOS 15.1.1
    CPU: (10) arm64 Apple M1 Max
    Memory: 1.07 GB / 64.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 20.18.1 - ~/.nvm/versions/node/v20.18.1/bin/node
    npm: 10.8.2 - ~/.nvm/versions/node/v20.18.1/bin/npm
    pnpm: 9.0.6 - ~/Library/pnpm/pnpm
  Browsers:
    Brave Browser: 131.1.73.97
    Chrome: 131.0.6778.140
    Firefox Nightly: 126.0a1
    Safari: 18.1.1
  npmPackages:
    @react-router/dev: ^7.0.2 => 7.0.2 
    @react-router/node: ^7.0.2 => 7.0.2 
    @react-router/serve: ^7.0.2 => 7.0.2 
    react-router: ^7.0.2 => 7.0.2 
    vite: ^5.4.11 => 5.4.11

Used Package Manager

npm

Expected Behavior

Dev server running on HTTPS should work.

Actual Behavior

Dev server running on HTTPS doesn't work.

[iwan-uschka]

Is it related and worth noting that undici (https://github.com/remix-run/react-router/blob/main/package.json#L108) now marks http/2 support as stable in https://github.com/nodejs/undici/releases/tag/v7.1.0?

[timdorr]

What happens if you set your own server.https options? https://vite.dev/config/server-options.html#server-https

I'm using Remix+Vite with SSL myself (with some certs from mkcert) and don't have this issue. If it's helpful, this is my config:

import { resolve } from 'path'
import { existsSync, readFileSync } from 'fs'

import { vitePlugin as remix } from '@remix-run/dev'
import { defineConfig } from 'vite'
import tsconfigPaths from 'vite-tsconfig-paths'

const crtPath = resolve(__dirname, 'tls.crt')
const keyPath = resolve(__dirname, 'tls.key')

const httpsOptions = existsSync(crtPath)
  ? {
      cert: readFileSync(crtPath),
      key: readFileSync(keyPath)
    }
  : {}

export default defineConfig({
  server: {
    port: 1234,
    host: 'localhost',
    https: httpsOptions
  },
  plugins: [
    remix({
      future: {
        v3_routeConfig: true,
        v3_fetcherPersist: true,
        v3_relativeSplatPath: true,
        v3_throwAbortReason: true,
        v3_singleFetch: true,
        v3_lazyRouteDiscovery: true
      }
    }),
    tsconfigPaths()
  ]
})

[Inkvii]

@timdorr
reproduced same error on fresh react router v7 with https. Error

[vite] Internal server error: Headers.set: ":method" is an invalid header name.
      at Object.webidl.errors.exception (node:internal/deps/undici/undici:3610:14)
      at Object.webidl.errors.invalidArgument (node:internal/deps/undici/undici:3621:28)
      at _Headers.set (node:internal/deps/undici/undici:8898:31)

Error occurs by adding config to vite.config.ts.

server: {
	host: "my.host.com",
	https: {
		key: fs.readFileSync("./key.pem"),
		cert: fs.readFileSync("./cert.pem"),
	},
},

Just for clarification - this happens ONLY if you try to use react-router. If you init project with https://remix.run/docs/en/main/start/quickstart (just like you seem to have) there is no error and https works

[iwan-uschka]

Thank you @timdorr. I'm having the same problems after following your suggestion and configuring https on my own using a self signed certificate.

[stephencattaneo]

FWIW the proxy: {}, workaround mentioned here remix-run/remix#7867 works

[neilhsmith]

Same issue here when setting the https option manually with self signed certs. But the empty proxy option does work for me too.