Return error when bulkload pending list hit limit (#17570)

Signed-off-by: groot <yihua.mo@zilliz.com>

internal/rootcoord/import_manager.go

@@ -282,13 +282,11 @@ func (m *importManager) importJob(ctx context.Context, req *milvuspb.ImportReque
 			taskCount = len(req.Files)
 		}
 
-		// task queue size has a limit, return error if import request contains too many data files
+		// task queue size has a limit, return error if import request contains too many data files, and skip entire job
 		if capacity-length < taskCount {
-			resp.Status = &commonpb.Status{
-				ErrorCode: commonpb.ErrorCode_IllegalArgument,
-				Reason:    "Import task queue max size is " + strconv.Itoa(capacity) + ", currently there are " + strconv.Itoa(length) + " tasks is pending. Not able to execute this request with " + strconv.Itoa(taskCount) + " tasks.",
-			}
-			return
+			err = fmt.Errorf("import task queue max size is %v, currently there are %v tasks is pending. Not able to execute this request with %v tasks", capacity, length, taskCount)
+			log.Error(err.Error())
+			return err
 		}
 
 		bucket := ""

internal/rootcoord/import_manager_test.go

@@ -19,6 +19,7 @@ package rootcoord
 import (
 	"context"
 	"errors"
+	"strconv"
 	"sync"
 	"testing"
 	"time"
@@ -260,6 +261,12 @@ func TestImportManager_ImportJob(t *testing.T) {
 	resp = mgr.importJob(context.TODO(), rowReq, colID, 0)
 	assert.Equal(t, len(rowReq.Files)-2, len(mgr.pendingTasks))
 	assert.Equal(t, 2, len(mgr.workingTasks))
+
+	for i := 0; i <= 32; i++ {
+		rowReq.Files = append(rowReq.Files, strconv.Itoa(i))
+	}
+	resp = mgr.importJob(context.TODO(), rowReq, colID, 0)
+	assert.NotEqual(t, commonpb.ErrorCode_Success, resp.Status.ErrorCode)
 }
 
 func TestImportManager_AllDataNodesBusy(t *testing.T) {