Websocket can't connect from a browser to a server

[Denis Mihailovich]

I built a client app and a server app both based on boost::beast. There are like https://www.boost.org/doc/libs/develop/libs/beast/example/websocket/client/sync-ssl/websocket_client_sync_ssl.cpp and https://www.boost.org/doc/libs/develop/libs/beast/example/websocket/server/sync-ssl/websocket_server_sync_ssl.cpp.

As usual applications they connect well. But when I compiled the client with emscripten, I can't connect to the server.

In CXX_FLAGS I use "-s WEBSOCKET_URL=wss:// -s WEBSOCKET_SUBPROTOCOL='text'".

I built openssl in emscripten and link to it.

I generated a certificate and use it in both apps.

But in any case I get

```

sslv3 alert certificate unknown (SSL routines)

```

How should I use ssl in webasm? How should I use certificates? Did anybody do something like that?

[Floh]

My guess is that websocket_client_sync_ssl.cpp is implementing a websocket client on top of 'raw' SSL and TCP (which is what's needed to talk to a websocket server from a native application, but is pointless in the browser).

Browsers already contain such a websocket client in form of the WebSocket Javascript API (https://developer.mozilla.org/en-US/docs/Web/API/WebSockets_API), Emscripten offers two API wrappers over websockets, one that's basically a 'POSIX socket emulation', and another that's a direct wrapper of the Javascript API:

https://emscripten.org/docs/porting/networking.html