Inconsistent and Erroring Behavior When Using EF OwnsOne/OwnsMany Mapping

[rtablada]

DESCRIPTION

When using EF OwnsOne/OwnsMany properties for nested or complex data structures/mappings JADNC 5 returns inconsistent results, nulls, or errors depending on use of include or sparse fieldsets.

• For regular requests with no sparse fields and no includes, properties mapped with OwnsOne act as expected
• When includes for other models are requested properties mapped with OwnsOne will return as null or invalid results
• When using sparse fields on a resource with OwnsOne mappings, a tracking error is thrown.

STEPS TO REPRODUCE

Full reproduction project: https://github.com/rtablada/JsonApiDotnetExamples

EXPECTED BEHAVIOR

Attrs which expose properties from OwnsOne should allow regular Attr behavior and work with include and fields as any other exposed attribute

ACTUAL BEHAVIOR

OwnsOne Attr properties...

• return expected result with no complex query string
• return null when include operations are requested from query string
• error when sparse fields are requested for OwnsOne attribute

VERSIONS USED

• JsonApiDotNetCore version: 5.1.2
• ASP.NET Core version: 7.0.0
• Entity Framework Core version: 7.0.4
• Database provider: PG for example project ☝🏽 (occurs with MSSQL as well)

[bkoelman]

Hi @rtablada, thanks for reporting this and providing great repro instructions.

I've verified that #1272 fixes the two cases from your repro, but you may want to do additional testing. Until now, we didn't have any tests for using owned entities. I haven't looked into OwnsMany usage.

One thing to be aware of: Partial updates do not preserve existing values within statistics. For example:

PATCH https://localhost:7175/countries/1 HTTP/1.1

{
  "data": {
    "type": "countries",
    "id": "1",
    "attributes": {
      "statistics": {
        "population": 456
      }
    }
  }
}

would clear the existing value of gdp. Although EF Core can update just the Population column, JSON:API has no concept of merging the individual fields within an attribute. If you're in need of that, JSON columns may better suit your needs. Adding non-MSSQL support is on the roadmap of EF Core 8.