Reject too large elements to the queue

Without this change, the requests without deadline will block forever until the space is available which will never be.

Signed-off-by: Bogdan Drutu <[email protected]>

Author: bogdandrutu

exporter/exporterhelper/internal/queuebatch/memory_queue.go

@@ -21,6 +21,7 @@ var blockingDonePool = sync.Pool{
 }
 
 var errInvalidSize = errors.New("invalid element size")
+var errSizeTooLarge = errors.New("element size too large")
 
 // memoryQueueSettings defines internal parameters for boundedMemoryQueue creation.
 type memoryQueueSettings[T any] struct {
@@ -74,6 +75,11 @@ func (mq *memoryQueue[T]) Offer(ctx context.Context, el T) error {
 		return errInvalidSize
 	}
 
+	// If element larger than the capacity, will never been able to add it.
+	if elSize > mq.cap {
+		return errSizeTooLarge
+	}
+
 	done, err := mq.add(ctx, el, elSize)
 	if err != nil {
 		return err

exporter/exporterhelper/internal/queuebatch/memory_queue_test.go

@@ -97,6 +97,11 @@ func TestMemoryQueueOfferInvalidSize(t *testing.T) {
 	require.ErrorIs(t, q.Offer(context.Background(), -1), errInvalidSize)
 }
 
+func TestMemoryQueueRejectOverCapacityElements(t *testing.T) {
+	q := newMemoryQueue[int64](memoryQueueSettings[int64]{sizer: sizerInt64{}, capacity: 7, blockOnOverflow: true})
+	require.ErrorIs(t, q.Offer(context.Background(), 8), errSizeTooLarge)
+}
+
 func TestMemoryQueueOfferZeroSize(t *testing.T) {
 	q := newMemoryQueue[int64](memoryQueueSettings[int64]{sizer: sizerInt64{}, capacity: 1})
 	require.NoError(t, q.Offer(context.Background(), 0))