improve ServeGuard a bit

crates/re_web_viewer_server/src/lib.rs

@@ -13,11 +13,6 @@ use std::{
     sync::{atomic::AtomicBool, Arc},
 };
 
-#[cfg(feature = "sync")]
-mod sync;
-#[cfg(feature = "sync")]
-pub use sync::WebViewerServerHandle;
-
 pub const DEFAULT_WEB_VIEWER_SERVER_PORT: u16 = 9090;
 
 // See `Cargo.toml` docs for the `__ci` feature for more information about the `disable_web_viewer_server` cfg:
@@ -42,10 +37,6 @@ pub enum WebViewerServerError {
 
     #[error("Failed to create server at address {0}: {1}")]
     CreateServerFailed(String, Box<dyn std::error::Error + Send + Sync + 'static>),
-
-    #[cfg(feature = "sync")]
-    #[error("Failed to spawn web viewer thread: {0}")]
-    ThreadSpawnFailed(#[from] std::io::Error),
 }
 
 // ----------------------------------------------------------------------------

crates/rerun/src/clap.rs

@@ -85,23 +85,16 @@ pub struct RerunArgs {
 /// were passed in.
 /// This object makes sure they live long enough and get polled as needed.
 #[doc(hidden)]
+#[derive(Default)]
 pub struct ServeGuard {
     block_on_drop: bool,
 }
 
-// TODO:
-impl Default for ServeGuard {
-    fn default() -> Self {
-        Self {
-            block_on_drop: false,
-        }
-    }
-}
-
 impl Drop for ServeGuard {
     fn drop(&mut self) {
         if self.block_on_drop {
             eprintln!("Sleeping indefinitely while serving web viewer... Press ^C when done.");
+            // TODO(andreas): It would be a lot better if we had a handle to the web server and could call `block_until_shutdown` on it.
             std::thread::sleep(std::time::Duration::from_secs(u64::MAX));
         }
     }