[usage] Batch list workspace instances in range

components/usage/pkg/db/dbtest/workspace_instance.go

@@ -24,7 +24,7 @@ func NewWorkspaceInstance(t *testing.T, instance db.WorkspaceInstance) db.Worksp
 		id = instance.ID
 	}
 
-	workspaceID := generateWorkspaceID()
+	workspaceID := GenerateWorkspaceID()
 	if instance.WorkspaceID != "" {
 		workspaceID = instance.WorkspaceID
 	}

components/usage/pkg/db/workspace_instance.go

@@ -70,13 +70,17 @@ func (i *WorkspaceInstance) TableName() string {
 // - instances which only just started in the period specified
 func ListWorkspaceInstancesInRange(ctx context.Context, conn *gorm.DB, from, to time.Time) ([]WorkspaceInstance, error) {
 	var instances []WorkspaceInstance
+	var instancesInBatch []WorkspaceInstance
 	tx := conn.WithContext(ctx).
 		Where(
 			conn.Where("stoppedTime >= ?", TimeToISO8601(from)).Or("stoppedTime = ?", ""),
 		).
 		Where("creationTime < ?", TimeToISO8601(to)).
 		Where("startedTime != ?", "").
-		Find(&instances)
+		FindInBatches(&instancesInBatch, 1000, func(_ *gorm.DB, _ int) error {
+			instances = append(instances, instancesInBatch...)
+			return nil
+		})
 	if tx.Error != nil {
 		return nil, fmt.Errorf("failed to list workspace instances: %w", tx.Error)
 	}

components/usage/pkg/db/workspace_instance_test.go

@@ -191,3 +191,29 @@ func TestListWorkspaceInstancesInRange(t *testing.T) {
 
 	require.Len(t, retrieved, len(valid))
 }
+
+func TestListWorkspaceInstancesInRange_InBatches(t *testing.T) {
+	conn := db.ConnectForTests(t)
+
+	workspaceID := "gitpodio-gitpod-gyjr82jkfnd"
+	var instances []db.WorkspaceInstance
+	for i := 0; i < 1100; i++ {
+		instances = append(instances, dbtest.NewWorkspaceInstance(t, db.WorkspaceInstance{
+			ID:           uuid.New(),
+			WorkspaceID:  workspaceID,
+			CreationTime: db.NewVarcharTime(time.Date(2022, 05, 15, 12, 00, 00, 00, time.UTC)),
+			StartedTime:  db.NewVarcharTime(time.Date(2022, 05, 15, 12, 00, 00, 00, time.UTC)),
+			StoppedTime:  db.NewVarcharTime(time.Date(2022, 05, 15, 13, 00, 00, 00, time.UTC)),
+		}))
+
+	}
+
+	tx := conn.CreateInBatches(&instances, 1000)
+	require.NoError(t, tx.Error)
+
+	startOfMay := time.Date(2022, 05, 1, 0, 00, 00, 00, time.UTC)
+	startOfJune := time.Date(2022, 06, 1, 0, 00, 00, 00, time.UTC)
+	results, err := db.ListWorkspaceInstancesInRange(context.Background(), conn, startOfMay, startOfJune)
+	require.NoError(t, err)
+	require.Len(t, results, len(instances))
+}