transaction_order.go

func TestTransferTxDeadlock(t *testing.T) {
	store := NewStore(testDB)

	sourceAccount := CreateRandomAccount(t)
	targetAccount := CreateRandomAccount(t)
	fmt.Println(">> before:", sourceAccount.Balance, targetAccount.Balance)

	n := 10
	amount := int64(10)
	errs := make(chan error)

	for i := 0; i < n; i++ {
		sourceAccountID := sourceAccount.ID
		targetAccountID := targetAccount.ID

		if i%2 == 1 {
			sourceAccountID = targetAccount.ID
			sourceAccountID = sourceAccount.ID
		}

		go func() {
			_, err := store.transferTx(context.Background(), AccountTransferTxParams{
				SourceAccountID: sourceAccountID,
				TargetAccountID:   targetAccountID,
				Amount:        amount,
			})

			errs <- err
		}()
	}

	for i := 0; i < n; i++ {
		err := <-errs
		require.NoError(t, err)
	}

	// check the final updated balance
	updatedAccount1, err := store.GetAccountDetails(context.Background(), sourceAccount.ID)
	require.NoError(t, err)

	updatedAccount2, err := store.GetAccountDetails(context.Background(), targetAccount.ID)
	require.NoError(t, err)

	fmt.Println(">> after:", updatedAccount1.Balance, updatedAccount2.Balance)
	require.Equal(t, sourceAccount.Balance, updatedAccount1.Balance)
	require.Equal(t, targetAccount.Balance, updatedAccount2.Balance)
}