I am prototyping an Emscripten httplib::Client build using the Emulated POSIX TCP Sockets over WebSockets tutorial.
For the work, see this commit: 49b526c1ec4a8c09bba0f5163c004024b5130a8c.

Are you interested in this kind of development?

I’m not entirely convinced it’s a good idea myself, but the Emscripten Fetch API is much more difficult to use and less documented compared to cpp-httplib.

With my prototype, I can build and run the following small example in a browser:

// main.cpp #include <httplib.h> #include <print> int main() { #ifdef __EMSCRIPTEN__ httplib::emscripten_init_websocket("ws://localhost:8080"); #endif httplib::Client cli("http://yhirose.github.io"); auto res = cli.Get("/hi"); std::println("Status: {}", res->status); std::println("Body: {}", res->body); return 0; }

The build command and execution with emrun are as follows:

em++ -std=c++23 -o index.html main.cpp -lwebsocket.js -sPROXY_POSIX_SOCKETS -pthread -sPROXY_TO_PTHREAD -sMEMORY64 -sEXIT_RUNTIME

This approach requires the Emscripten bridge socket server, websocket_to_posix_proxy, or a Node.js WebSocket server implementation. I haven’t yet figured out how to deploy this in a production environment, hence my questions about the prototype.

I started a functional project demonstrator.