Aurelius Replicate: Succeeding items in many-valued list is not saved, only first item is saved

BIZ TMS Aurelius
1

I have an Invoice object, it has Invoice Items. The Invoice Items is a many-valued collection. The invoice itself has 0 id so it should save, but there are aggregates that exist in the db but are transient. So I used replicate on the Invoice so it merges existing objects from db and saves the new objects. The problem here is the Invoice Items are not fully saved. All of the items have 0 as id but it only saves the first item and the next items became invalid, 0 id and nil aggregates.

Notes:

  • I removed some aggregates from TAureliusInvoice to make it concise.
  • I found out that it successfully saves all items when I sometimes go to debug, step to Replicate and try to inspect the Invoice and its aggregate in the IDE, and continue execution. I assessed that it could be a memory leak problem. But at this point, I don't have any idea.
  [Entity]
  [Table('Invoice')]
  [Id('Id', TIdGenerator.IdentityOrSequence)]
  TAureliusInvoice = class
  private
    FId: Integer;
    FItems: TObjectList<TAureliusInvoiceItem>;
  public
    constructor Create(
      const AId: Integer;
      const AItems: TObjectList<TAureliusInvoiceItem>;);

    [Column('Id', [TColumnProp.Unique, TColumnProp.Required])]
    property Id: Integer read FId write FId;

    [ManyValuedAssociation([TAssociationProp.Required], CascadeTypeAll)]
    [ForeignJoinColumn('ItemInvoiceId', [TColumnProp.Required])]
    property Items: TObjectList<TAureliusInvoiceItem> read FItems write FItems;
  end;

  [Entity]
  [Table('InvoiceItem')]
  [Id('Id', TIdGenerator.IdentityOrSequence)]
  TAureliusInvoiceItem = class
  private
    FId: Integer;
    FTransactionId: Integer;
    FQuantity: Integer;
    FItem: TAureliusItem;
    FPrice: Currency;
    FDiscounts: TObjectList<TAureliusTransactionItemDiscount>;
  public
    constructor Create(
      const AId: Integer;
      const ATransactionId: Integer;
      const AItem: TAureliusItem;
      const AQuantity: Integer;
      const APrice: Currency;
      const ADiscounts: TObjectList<TAureliusTransactionItemDiscount>);

    function GetItemRefId: Integer;
    function GetItemId: Integer;

    [Column('Id', [TColumnProp.Unique, TColumnProp.Required])]
    property Id: Integer read FId write FId;

    property TransactionId: Integer read FTransactionId write FTransactionId;

    [Association([TAssociationProp.Required], [TCascadeType.Refresh])]
    [JoinColumn('ItemId', [TColumnProp.Required])]
    property Item: TAureliusItem read FItem write FItem;

    [Column('Quantity', [TColumnProp.Required])]
    property Quantity: Integer read FQuantity write FQuantity;

    [Column('Price', [TColumnProp.Required])]
    property Price: Currency read FPrice write FPrice;

    [ManyValuedAssociation([TAssociationProp.Required], CascadeTypeAll)]
    [ForeignJoinColumn('TransactionItemId', [TColumnProp.Required])]
    property Discounts: TObjectList<TAureliusTransactionItemDiscount> read FDiscounts write FDiscounts;
  end;
2

One off thing I noticed is that you don't have parameterless constructors. You should be creating your TList and TObjectList objects in your constructor, and destroying them in destructor, following the pattern described in the documentation.

Other than this, I'm afraid I need a sample project reproducing the issue. Are you able to provide it, please?

1 Like
3

I've got a sample project. It uses a mysql db, there's a database.ini beside the exe to configure the connectivity. There's also a mysql dump in the root folder. Apologies for using mysql, I could not get sqlite working.

4

In this case, the first two items are saved the rest not. See picture:

image
image844×936 26.1 KB

5

Hi. Can I get help on this. Even not using replicate, the problem does persist.

6

I found the issue. In the InternalMerge, Explorer.CopyFieldValues is not called for succeeding items. Im guessing it is because the first item with ID = 0 is added to the ProcessedObjects, and when the second item ID = 0 pass to (not ContainerKey) check is fails and can't call the CopyFieldValues. The Object with default values are added to the item instead. Is this intended? If so, what are the other options to save/update all items in a list.

7

I fixed the problem. On ObjectFactory.CreateInstance reuses a memory that exists as key in the ProcessedObjs dictionary. That is why the condition (not ProcessedObjs.ContainsKey(Original)) fails and skips the CopyFieldValues.

The solution is I changed the TDictionary<TObject, TObject> to TDictionary<string, TObject>. I used GUID returned from ToString of TObject to create a really unique identifier. It worked.

8

Well, your code as several issues. I didn't understand your solution, you modified TMS Aurelius source code?

First, you are creating the object list as owning the invoice items, that is wrong. You should create the list as TList<T>, or at least pass False In the constructor:


    var Items := TObjectList<TInvoiceItem>.Create(False);

...

constructor TInvoice.Create;
begin
  FItems := TObjectList<TInvoiceItem>.Create(False);
end;

That was causing an invalid pointer operation at the end of application.

Second, you are creating several invoice items with the same name:

    Items.Add(TInvoiceItem.Create(0, 'Fried Chicken'));
    Items.Add(TInvoiceItem.Create(0, 'Fried Chicken'));
    Items.Add(TInvoiceItem.Create(0, 'Fried Chicken'));
    Items.Add(TInvoiceItem.Create(0, 'Fried Chicken'));
    Items.Add(TInvoiceItem.Create(0, 'Fried Chicken'));

But you created the invoice item name as unique:

    [Column('Name', [TColumnProp.Unique, TColumnProp.Required])]
    property Name: string read FName write FName;

So the insert will fail due to the business logic you created yourself:

ESQLiteException: UNIQUE constraint failed: InvoiceItem.Name

Now, if I use different names for each invoice item:

    var Items := TObjectList<TInvoiceItem>.Create(False);
    Items.Add(TInvoiceItem.Create(0, 'Fried Chicken1'));
    Items.Add(TInvoiceItem.Create(0, 'Fried Chicken2'));
    Items.Add(TInvoiceItem.Create(0, 'Fried Chicken3'));
    Items.Add(TInvoiceItem.Create(0, 'Fried Chicken4'));
    Items.Add(TInvoiceItem.Create(0, 'Fried Chicken5'));

The application works fine:

{
    "FId": 1,
    "FItems": {
        "FOwnsObjects": false,
        "FListHelper": [
            {
                "FId": 1,
                "FName": "Fried Chicken1"
            },
            {
                "FId": 2,
                "FName": "Fried Chicken2"
            },
            {
                "FId": 3,
                "FName": "Fried Chicken3"
            },
            {
                "FId": 4,
                "FName": "Fried Chicken4"
            },
            {
                "FId": 5,
                "FName": "Fried Chicken5"
            }
        ],
        "FComparer": {}
    },
    "FRecordedOn": "1899-12-30T00:00:00.000-02:00"
}