message: show error if cannot bind port
diff: @@ -2,6 +2,7 @@ use crate::prelude::*;
  use crate::service::handlers::{get_api_v0, get_status, post_api_v0};
  use jsonrpc_core::Call;
  use std::net::SocketAddr;
  +use std::process;
  use warp::Filter;
  mod client;
  @@ -39,5 +40,14 @@ pub async fn service_main() {
  .or(path_v0_post)
  .with(warp::log("MAIN"));
  - warp::serve(routes).run(addr).await;
  + let server = warp::serve(routes);
  +
  + let (addr, fut) = server.try_bind_ephemeral(addr).unwrap_or_else(|e| {
  + println!("Error connecting: {}", e);
  + process::exit(1);
  + });
  +
  + println!("listening on http://{}", addr);
  +
  + fut.await;
  }
  