Error With Temporals using InMemory Provider

[gafken]

When I'm using the InMemory Provider for EfCore 6.0 it keeps telling me that 'Example.SysStart' cannot be found. That's actually accurate as SysStart only exists on the ExampleHist Table. With the standard SQL Provider we run into no issues running our configuration. If I add the properties to the entity the InMemory Provider works fine but the SQL Provider complains that a shadow property cannot be explicitly defined.

entity.HasComment("Irrelevant Comment.")
                .ToTable(tb => tb.IsTemporal(ttb =>
    {
        ttb.UseHistoryTable("ExampleHist", "scExample");
        ttb.HasPeriodStart("SysStart") //error here
            .HasColumnName("SysStart");
        ttb
            .HasPeriodEnd("SysEnd")
            .HasColumnName("SysEnd");
    }));

The property 'Example.SysStart' could not be found. Ensure that the property exists and has been included in the model.
at IReadOnlyEntityType.GetProperty(String name)
at IMutableEntityType.GetProperty(String name)
at TemporalPeriodPropertyBuilder.HasColumnName(String name)
at <>c.<Configure>b__0_22(TemporalTableBuilder`1 ttb) line 19
at SqlServerTableBuilderExtensions.IsTemporal[TEntity](TableBuilder`1 tableBuilder, Action`1 buildAction)
at <>c.<Configure>b__0_0(TableBuilder`1 tb) line 16
at RelationalEntityTypeBuilderExtensions.ToTable[TEntity](EntityTypeBuilder`1 entityTypeBuilder, Action`1 buildAction)
at ExampleConfiguration.Configure(EntityTypeBuilder`1 entity) line 15

and

"Period property 'Example.SysStart' must be a shadow property."

[roji]

Temporal tables are a feature of SQL Server, and are not supported in the InMemory provider. I'd recommend reading this doc page on the different testing strategies - we generally discourage using the InMemory provider.

[gafken]

We're not trying to test our Database/Connection, we just need a way to check that the logic operates in our codebase via unit tests. I'd be perfectly fine with a solution that ignores the temporal configuration altogether for inmemory, so long as it doesn't throw an error because of the configuration.

Just to reiterate, this is for Unit Testing and in no way are we relying on it for persistence or context maintenance.

[ajcvickers]

@gafken Why do you need to use the in-memory provider for that?

[roji]

@gafken you can add the missing temporal properties as shadow properties only for InMemory by doing a provider check when configuring the model, e.g.:

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    if (Database.IsInMemory())
    {
        modelBuilder.Entity<SomeEntityType>(b =>
        {
            b.Property<DateTime>("SysStart");
            b.Property<DateTime>("SysEnd");
        });
    }
}

[gafken]

@roji That solved my issue, thanks a bunch! :)

[bluebaroncanada]

Is that acceptable? Those files need to be overwriteable and autogenerated; right?

[ajcvickers]

@bluebaroncanada If you're scaffolding the DbContext code, then use the partial method instead.

[iSatishYadav]

@gafken you can add the missing temporal properties as shadow properties only for InMemory by doing a provider check when configuring the model, e.g.:

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    if (Database.IsInMemory())
    {
        modelBuilder.Entity<SomeEntityType>(b =>
        {
            b.Property<DateTime>("SysStart");
            b.Property<DateTime>("SysEnd");
        });
    }
}

Thanks @gafken, this worked for me as well. One side note, I had to add this code before:

base.OnModelCreating(modelBuilder);

Saved my day.