kgrzybek/modular-monolith-with-ddd · error · InvalidCommandException

Pricelist item for changing must exist.

Error message

Pricelist item for changing must exist.

What it means

Thrown by ChangePriceListItemAttributesCommandHandler when _aggregateStore.Load returns null for the PriceListItemId. Changing attributes requires the aggregate to exist; a missing item aborts with InvalidCommandException (HTTP 400) before applying ChangeAttributes.

Source

Thrown at src/Modules/Payments/Application/PriceListItems/ChangePriceListItemAttributes/ChangePriceListItemAttributesCommandHandler.cs:24

namespace CompanyName.MyMeetings.Modules.Payments.Application.PriceListItems.ChangePriceListItemAttributes
{
    internal class ChangePriceListItemAttributesCommandHandler : ICommandHandler<ChangePriceListItemAttributesCommand>
    {
        private readonly IAggregateStore _aggregateStore;

        public ChangePriceListItemAttributesCommandHandler(IAggregateStore aggregateStore)
        {
            _aggregateStore = aggregateStore;
        }

        public async Task Handle(ChangePriceListItemAttributesCommand command, CancellationToken cancellationToken)
        {
            var priceListItem = await _aggregateStore.Load(new PriceListItemId(command.PriceListItemId));

            if (priceListItem == null)
            {
                throw new InvalidCommandException(["Pricelist item for changing must exist."]);
            }

            priceListItem.ChangeAttributes(
                command.CountryCode,
                SubscriptionPeriod.Of(command.SubscriptionPeriodCode),
                PriceListItemCategory.Of(command.CategoryCode),
                MoneyValue.Of(command.PriceValue, command.PriceCurrency));

            _aggregateStore.AppendChanges(priceListItem);
        }
    }
}

View on GitHub (pinned to 91c8ef24b4)

Solutions

1. Confirm the item exists and belongs to the right country/period scope.
2. Validate the command's CountryCode/SubscriptionPeriodCode/CategoryCode values are in the allowed catalogs (these feed MoneyValue/SubscriptionPeriod.Of which can also throw).
3. Pre-check existence in the controller and return 404.
4. Map InvalidCommandException to 400/404 at the API boundary.

Example fix

// before
await _commandDispatcher.SendAsync(new ChangePriceListItemAttributesCommand(itemId, countryCode, periodCode, categoryCode, value, currency));

// after
var item = await _priceListQueries.GetItemAsync(itemId);
if (item is null) return NotFound("Price list item not found.");
await _commandDispatcher.SendAsync(new ChangePriceListItemAttributesCommand(itemId, countryCode, periodCode, categoryCode, value, currency));

var item = await _priceListQueries.GetItemAsync(itemId);
if (item is null) return NotFound("Price list item not found.");
await _commandDispatcher.SendAsync(new ChangePriceListItemAttributesCommand(itemId, countryCode, periodCode, categoryCode, value, currency));

public static bool IsValidChangeCommand(ChangePriceListItemAttributesCommand c) =>
    c.PriceListItemId != Guid.Empty
    && !string.IsNullOrWhiteSpace(c.CountryCode)
    && c.Value >= 0
    && !string.IsNullOrWhiteSpace(c.Currency);

try { await _commandDispatcher.SendAsync(cmd); }
catch (InvalidCommandException ex) when (ex.Errors.Any(m => m.Contains("must exist")))
{ return NotFound(new { errors = ex.Errors }); }

When it happens

Trigger: Dispatching ChangePriceListItemAttributesCommand for a non-existent id: wrong Guid, item deleted, wrong tenant, or stream not found.

Common situations: Editing a price list row in an admin grid that has since been deactivated/removed; cross-environment id copy; bulk import referencing stale ids.

Related errors

• Pricelist item for activation must exist.
• Pricelist item for deactivation must exist.
• Subscription for renewal must exist.
• Meeting commenting configuration for disabling commenting mu
• Meeting commenting configuration for enabling commenting mus

AI-assisted analysis of kgrzybek/modular-monolith-with-ddd@91c8ef24b4 (2026-08-13). Data as JSON: /api/errors/851445b9e27f7f1a. Report an issue: GitHub.