[pdm-devel] [PATCH datacenter-manager v2] ui: resource tree: use AsyncAbortGuard to cancel obsolete pending loads

[Dominik Csapak]

Currently, if a new serach term is given, a new load will occur if the
INPUT_BUFFER_MS time is reached. Any old in-flight API requests are not
canceled, and might still arrive.

To prevent that, use an AsyncAbortGuard so the old load will be aborted
whenever it is overwritten.

Signed-off-by: Dominik Csapak <d.csapak at proxmox.com>
---
changes from v1:
* use AsyncAbortGuard instead of AsyncPool, since that's the correct
  abstraction here.
* introduce a new Msg variant, so that we can overwrite the AsyncAbortGuard
  in the update method

replaces:
https://lore.proxmox.com/pdm-devel/20250416113232.2488103-1-d.csapak@proxmox.com/

 ui/src/widget/resource_tree.rs | 28 +++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/ui/src/widget/resource_tree.rs b/ui/src/widget/resource_tree.rs
index feff308..ddfd7cb 100644
--- a/ui/src/widget/resource_tree.rs
+++ b/ui/src/widget/resource_tree.rs
@@ -18,6 +18,7 @@ use pwt::{
         },
         ActionIcon, Column, Container, Fa, Panel, Progress, Row, Tooltip,
     },
+    AsyncAbortGuard,
 };
 use pwt_macros::{builder, widget};
 
@@ -88,6 +89,7 @@ async fn load_resources(search_term: String) -> Result<Vec<RemoteResources>, Err
 }
 
 pub enum Msg {
+    LoadRequest,
     Load,
     LoadResult(Result<Vec<RemoteResources>, Error>),
     RemoteListChanged(RemoteList),
@@ -101,6 +103,7 @@ pub struct PdmResourceTree {
     _context_listener: ContextHandle<RemoteList>,
     selection: Selection,
     _load_timeout: Option<Timeout>,
+    _load_guard: Option<AsyncAbortGuard>,
 }
 
 impl PdmResourceTree {}
@@ -117,7 +120,7 @@ impl Component for PdmResourceTree {
             .expect("No Remote list context provided");
 
         if !props.search_only || !props.search_term.is_empty() {
-            ctx.link().clone().send_message(Msg::Load);
+            ctx.link().clone().send_message(Msg::LoadRequest);
         }
 
         let store = TreeStore::new().view_root(false);
@@ -131,25 +134,32 @@ impl Component for PdmResourceTree {
             _context_listener,
             selection,
             _load_timeout: None,
+            _load_guard: None,
         }
     }
 
     fn update(&mut self, ctx: &Context<Self>, msg: Self::Message) -> bool {
         match msg {
-            Msg::Load => {
+            Msg::LoadRequest => {
                 let props = ctx.props();
                 let link = ctx.link().clone();
-                let search_term = props.search_term.clone();
-                if props.search_only && !search_term.is_empty() {
+                if props.search_only && !props.search_term.is_empty() {
                     self._load_timeout = Some(Timeout::new(INPUT_BUFFER_MS, move || {
-                        link.send_future(async move {
-                            Msg::LoadResult(load_resources(search_term).await)
-                        });
+                        link.send_message(Msg::Load);
                     }));
                     self.loading = true;
                 }
                 true
             }
+            Msg::Load => {
+                let props = ctx.props();
+                let link = ctx.link().clone();
+                let search_term = props.search_term.clone();
+                self._load_guard = Some(AsyncAbortGuard::spawn(async move {
+                    link.send_message(Msg::LoadResult(load_resources(search_term).await))
+                }));
+                false
+            }
             Msg::LoadResult(res) => {
                 match res {
                     Ok(result) => {
@@ -189,7 +199,7 @@ impl Component for PdmResourceTree {
                 let reload = self.remote_list.len() != list.len();
                 self.remote_list = list;
                 if reload && !self.remote_list.is_empty() {
-                    ctx.link().send_message(Msg::Load);
+                    ctx.link().send_message(Msg::LoadRequest);
                 }
                 true
             }
@@ -200,7 +210,7 @@ impl Component for PdmResourceTree {
         let props = ctx.props();
         if props.search_term != old_props.search_term {
             if !props.search_only || !props.search_term.is_empty() {
-                ctx.link().clone().send_message(Msg::Load);
+                ctx.link().clone().send_message(Msg::LoadRequest);
             } else if props.search_term.is_empty() {
                 // clear grid
                 ctx.link()
-- 
2.39.5