Websocket connection failed in dev mode and SSL

[simasch]

Description of the bug

After migrating the application from 14 to 23 we get this error when running in dev mode with Spring Boot dev tools:

Expected behavior

There shouldn't be an error in the dev mode

Minimal reproducible example

1. Create a new Vaadin 23 app
2. Create a self-signed certificate
3. Configure

   
   server.port=${PORT:8443}
   server.ssl.enabled=true
   server.ssl.protocol=TLS
   server.ssl.enabled-protocols=TLSv1.2
   server.ssl.key-store-type=PKCS12
   server.ssl.key-store=..\\..\\keyStore.p12
   server.ssl.key-store-password=xxx
   server.ssl.key-alias=1

### Versions

- Vaadin / Flow version: 23
- Java version: 17
- OS version: Windows 11

[mcollovati]

Url for websocket connection to dev server is based on current browser URL or PUSH url configuration, so when using https it is will be a wss://, however dev server is served over http.. Webpack can be configured to be served over https with a setting in webpack.config.json, but then AbstractDevServer fails to forward request because http protocol is hard-coded.

Just for the record, here is the https configuration for webpack.config.json

module.exports = merge(flowDefaults,
  {
      devServer: { https: true } 
  }
);

[Artur-]

I think we should do #13646 to solve this. It is the Spring Boot live reload server that it tries to connect to on port 35729, does webpack have any involvement here?

[mcollovati]

@Artur- You're completely right, webpack isn't involved here. Sorry