Moq dbContext if there are entities with jsonb (postgresql) - .net-core

Question

I try to moq my DbContext like in memory db. I use PostgreSql in my app, so I have entities with jsonb properties. For example:
[Table("examples")]
public class Example
{
/// <summary>
/// id (autogenerated by DB)
/// </summary>
[Column("id", TypeName = "bigserial")]
[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public long Id { get; set; }
/// <inheritdoc/>
[Column("layout_config", TypeName = "jsonb")]
[Required]
public LayoutConfigDto LayoutConfig { get; set; }
}
[Keyless]
public class LayoutConfigDto
{
/// <summary>
/// Координата X расположения виджета
/// </summary>
public byte X { get; set; }
/// <summary>
/// Координата Y расположения виджета
/// </summary>
public byte Y { get; set; }
}
so LayoutConfigDto just a model for JSON, that doesn't need a table. And doesn't need any relation or configuration for table.
Then I create Test class:
[TestFixture]
public class ExampleServiceTests
{
private IExampleService _exampleService;
[SetUp]
public void Setup()
{
DbContextOptions<ExampleDbContext> options = new DbContextOptionsBuilder<ExampleDbContext>()
.UseInMemoryDatabase(databaseName: "InMemoryExampleDatabase")
.Options;
ExampleDbContext dbContext = new(options);
new FakeDatabaseDataGenerator().Generate(dbContext);
Mock<ILogger<ExampleService>> mock = new();
_exampleService = new ExampleService(dbContext, mock.Object);
}
[Test]
[TestCase(0)]
[TestCase(3)]
public async Task GetExampleTest(long id)
{
ExampleModel example = await _exampleService.GetExample(id);
if (id <= 0)
{
Assert.AreEqual(example, null);
return;
}
Assert.AreNotEqual(null, example);
}
}
When I run GetExampleTest it fails on Exceptions like:
System.InvalidOperationException : Unable to determine the relationship represented by navigation 'UserWidgetModel.LayoutConfig' of type 'LayoutConfigDto'. Either manually configure the relationship, or ignore this property using the '[NotMapped]' attribute or by using 'EntityTypeBuilder.Ignore' in 'OnModelCreating'.
I can't use [NotMapped] attribute on LayoutConfig field, because I need to get it from DB and with pgsql driver all works and serializes. But with in memory db it fails. How can I change my Test to make it works? Is there any other options to mock db context?

Answer 1

The error it returns is pretty clear; it tells you what you need to do. If you can't use the [NotMapped] attribute, you need to configure a relationship for the fields it needs