From 69ab09c149fedb3f1b337c7419211f940f722c33 Mon Sep 17 00:00:00 2001
From: Tamo <tamo@meilisearch.com>
Date: Wed, 28 Aug 2024 15:17:10 +0200
Subject: [PATCH] ensure we never early exit when we have a permit and remove
 the warning when we implicitely drop a permit

---
 meilisearch/src/routes/indexes/facet_search.rs | 3 ++-
 meilisearch/src/routes/indexes/search.rs       | 6 ++++--
 meilisearch/src/routes/multi_search.rs         | 3 ++-
 meilisearch/src/search_queue.rs                | 4 +++-
 4 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/meilisearch/src/routes/indexes/facet_search.rs b/meilisearch/src/routes/indexes/facet_search.rs
index b1e57b865..1df80711d 100644
--- a/meilisearch/src/routes/indexes/facet_search.rs
+++ b/meilisearch/src/routes/indexes/facet_search.rs
@@ -93,8 +93,9 @@ pub async fn search(
             locales,
         )
     })
-    .await?;
+    .await;
     permit.drop().await;
+    let search_result = search_result?;
 
     if let Ok(ref search_result) = search_result {
         aggregate.succeed(search_result);
diff --git a/meilisearch/src/routes/indexes/search.rs b/meilisearch/src/routes/indexes/search.rs
index 89647c243..362bc9937 100644
--- a/meilisearch/src/routes/indexes/search.rs
+++ b/meilisearch/src/routes/indexes/search.rs
@@ -237,8 +237,9 @@ pub async fn search_with_url_query(
     let search_result = tokio::task::spawn_blocking(move || {
         perform_search(&index, query, search_kind, retrieve_vector, index_scheduler.features())
     })
-    .await?;
+    .await;
     permit.drop().await;
+    let search_result = search_result?;
     if let Ok(ref search_result) = search_result {
         aggregate.succeed(search_result);
     }
@@ -281,8 +282,9 @@ pub async fn search_with_post(
     let search_result = tokio::task::spawn_blocking(move || {
         perform_search(&index, query, search_kind, retrieve_vectors, index_scheduler.features())
     })
-    .await?;
+    .await;
     permit.drop().await;
+    let search_result = search_result?;
     if let Ok(ref search_result) = search_result {
         aggregate.succeed(search_result);
         if search_result.degraded {
diff --git a/meilisearch/src/routes/multi_search.rs b/meilisearch/src/routes/multi_search.rs
index b2ce05298..5fcb868c6 100644
--- a/meilisearch/src/routes/multi_search.rs
+++ b/meilisearch/src/routes/multi_search.rs
@@ -81,6 +81,7 @@ pub async fn multi_search_with_post(
                 perform_federated_search(&index_scheduler, queries, federation, features)
             })
             .await;
+            permit.drop().await;
 
             if let Ok(Ok(_)) = search_result {
                 multi_aggregate.succeed();
@@ -143,6 +144,7 @@ pub async fn multi_search_with_post(
                 Ok(search_results)
             }
             .await;
+            permit.drop().await;
 
             if search_results.is_ok() {
                 multi_aggregate.succeed();
@@ -162,7 +164,6 @@ pub async fn multi_search_with_post(
             HttpResponse::Ok().json(SearchResults { results: search_results })
         }
     };
-    permit.drop().await;
 
     Ok(response)
 }
diff --git a/meilisearch/src/search_queue.rs b/meilisearch/src/search_queue.rs
index 44a66ff82..ecdaaf3ff 100644
--- a/meilisearch/src/search_queue.rs
+++ b/meilisearch/src/search_queue.rs
@@ -48,8 +48,10 @@ impl Permit {
 }
 
 impl Drop for Permit {
+    /// The implicit drop implementation can still be called in multiple cases:
+    /// - We forgot to call the explicit one somewhere => this should be fixed on our side asap
+    /// - The future is cancelled while running and the permit dropped with it
     fn drop(&mut self) {
-        tracing::warn!("Internal error, a search permit was lazily dropped. If you see this message, please open an issue on the meilisearch repository at <https://github.com/meilisearch/meilisearch/issues/new?template=bug_report.md&title=[INTERNAL%20ERROR]%20Meilisearch%20lazily%20dropped%20a%20search%20permit>");
         let sender = self.sender.clone();
         // if the channel is closed then the whole instance is down
         std::mem::drop(tokio::spawn(async move { sender.send(()).await }));