From d8c1bd24f2bfbed3a968dfd260b1de88114ed8c9 Mon Sep 17 00:00:00 2001
From: congqixia <congqi.xia@zilliz.com>
Date: Mon, 28 Oct 2024 18:54:23 +0800
Subject: [PATCH] enhance: Utilize proxy metacache for `HasCollection` (#37185)

Related to #37183

Utilize proxy metacache for `HasCollection` request, if collection
exists in metacache, it could be deducted that collection must exist in
system.

Signed-off-by: Congqi Xia <congqi.xia@zilliz.com>
---
 internal/proxy/task.go      | 13 ++++++++++---
 internal/proxy/task_test.go | 17 ++++++++++++++++-
 2 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/internal/proxy/task.go b/internal/proxy/task.go
index 850bbd25fd..5bfcf4ab3f 100644
--- a/internal/proxy/task.go
+++ b/internal/proxy/task.go
@@ -564,9 +564,16 @@ func (t *hasCollectionTask) PreExecute(ctx context.Context) error {
 }
 
 func (t *hasCollectionTask) Execute(ctx context.Context) error {
-	var err error
-	t.result, err = t.rootCoord.HasCollection(ctx, t.HasCollectionRequest)
-	return merr.CheckRPCCall(t.result, err)
+	_, err := globalMetaCache.GetCollectionID(ctx, t.HasCollectionRequest.GetDbName(), t.HasCollectionRequest.GetCollectionName())
+	t.result = &milvuspb.BoolResponse{}
+	// error other than
+	if err != nil && !errors.Is(err, merr.ErrCollectionNotFound) {
+		return err
+	}
+	// if collection not nil, means error is ErrCollectionNotFound, result is false
+	// otherwise, result is true
+	t.result.Value = (err == nil)
+	return nil
 }
 
 func (t *hasCollectionTask) PostExecute(ctx context.Context) error {
diff --git a/internal/proxy/task_test.go b/internal/proxy/task_test.go
index e60d046f2d..2eb4b219e2 100644
--- a/internal/proxy/task_test.go
+++ b/internal/proxy/task_test.go
@@ -1081,8 +1081,23 @@ func TestHasCollectionTask(t *testing.T) {
 	err = task.PreExecute(ctx)
 	assert.Error(t, err)
 
-	rc.updateState(commonpb.StateCode_Abnormal)
 	task.CollectionName = collectionName
+
+	// invalidate collection cache, trigger rootcoord rpc
+	globalMetaCache.RemoveCollection(ctx, dbName, collectionName)
+
+	// rc return collection not found error
+	rc.describeCollectionFunc = func(ctx context.Context, request *milvuspb.DescribeCollectionRequest) (*milvuspb.DescribeCollectionResponse, error) {
+		return nil, merr.WrapErrCollectionNotFoundWithDB(dbName, collectionName)
+	}
+	err = task.PreExecute(ctx)
+	assert.NoError(t, err)
+	err = task.Execute(ctx)
+	assert.NoError(t, err)
+	assert.False(t, task.result.GetValue())
+
+	// rootcoord failed to get response
+	rc.updateState(commonpb.StateCode_Abnormal)
 	err = task.PreExecute(ctx)
 	assert.NoError(t, err)
 	err = task.Execute(ctx)