Add refresh button to the collection UI (rerun-io#9145)

title

<img width="585" alt="image"
src="https://github.com/user-attachments/assets/cee7913a-b5d8-4be6-80a6-3cb557524d59"
/>

Author: abey79

crates/viewer/re_redap_browser/src/collection_ui.rs

@@ -81,9 +81,17 @@ pub fn collection_ui(
     };
 
     egui::Frame::new().inner_margin(5.0).show(ui, |ui| {
-        if ui.button("Close").clicked() {
-            let _ = ctx.command_sender.send(Command::DeselectCollection);
-        }
+        ui.horizontal(|ui| {
+            if ui.button("Close").clicked() {
+                let _ = ctx.command_sender.send(Command::DeselectCollection);
+            }
+
+            if ui.button("Refresh").clicked() {
+                let _ = ctx
+                    .command_sender
+                    .send(Command::RefreshCollection(origin.clone()));
+            }
+        });
 
         egui_table::Table::new()
             .id_salt(table_id_salt)

crates/viewer/re_redap_browser/src/collections.rs

@@ -34,21 +34,20 @@ pub struct Collections {
 }
 
 impl Collections {
-    pub fn add(
+    pub fn fetch(
         &mut self,
         runtime: &AsyncRuntimeHandle,
         egui_ctx: &egui::Context,
         origin: re_uri::Origin,
     ) {
-        //TODO(ab): should we return error if the requested collection already exists? Or maybe just
-        // query it again.
-        self.collections.entry(origin.clone()).or_insert_with(|| {
+        self.collections.insert(
+            origin.clone(),
             RequestedObject::new_with_repaint(
                 runtime,
                 egui_ctx.clone(),
                 stream_catalog_async(origin),
-            )
-        });
+            ),
+        );
     }
 
     /// Convert all completed queries into proper collections.

crates/viewer/re_redap_browser/src/servers.rs

@@ -21,14 +21,24 @@ impl Server {
         let mut collections = Collections::default();
 
         //TODO(ab): For now, we just auto-download the default collection
-        collections.add(runtime, egui_ctx, origin.clone());
+        collections.fetch(runtime, egui_ctx, origin.clone());
 
         Self {
             origin,
             collections,
         }
     }
 
+    //TODO(ab): this should take a collection id in the future
+    fn refresh_default_collection(
+        &mut self,
+        runtime: &AsyncRuntimeHandle,
+        egui_ctx: &egui::Context,
+    ) {
+        self.collections
+            .fetch(runtime, egui_ctx, self.origin.clone());
+    }
+
     fn on_frame_start(&mut self) {
         self.collections.on_frame_start();
     }
@@ -131,6 +141,7 @@ pub enum Command {
     DeselectCollection,
     AddServer(re_uri::Origin),
     RemoveServer(re_uri::Origin),
+    RefreshCollection(re_uri::Origin),
 }
 
 impl RedapServers {
@@ -183,6 +194,12 @@ impl RedapServers {
             Command::RemoveServer(origin) => {
                 self.servers.remove(&origin);
             }
+
+            Command::RefreshCollection(origin) => {
+                self.servers.entry(origin).and_modify(|server| {
+                    server.refresh_default_collection(runtime, egui_ctx);
+                });
+            }
         }
     }