PublishedODataService EntityTypePointer never set — Studio Pro NRE in EntitySet.Check

[ako]

Summary

serializePublishedODataService (sdk/mpr/writer_odata.go:248) tries to resolve each EntitySet's owning EntityType through an internal map keyed by the wrong field. The lookup always returns empty, so the EntityTypePointer field is never written on ODataPublish\$EntitySet sub-documents. Studio Pro's EntitySet.Check (Mendix.Modeler.Integration.ODataServices.Publish.EntitySet.Check, line 53) then dereferences null and aborts the entire project checker with a NullReferenceException — hiding all other problems in the project, not just the published OData service.

Stack trace

System.AggregateException: One or more errors occurred. (Object reference not set to an instance of an object.)
 ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at Mendix.Modeler.Integration.ODataServices.Publish.EntitySet.Check(IProblems problems)
      in Mendix.Modeler.Integration/ODataServices/Publish/EntitySet.cs:line 53
   at Mendix.Modeler.Storage.TypeWalks.TypeWalk.ForEachObjectDo[TObject](...)
   ...
   at Mendix.Modeler.Core.View.Problems.BackgroundCheckRunner.Check(IProject project, CancellationToken cancellationToken)

Root cause

In sdk/mpr/writer_odata.go:

// Line 235 — map keyed by ExposedName
entityTypeIDMap[et.ExposedName] = etID

// Line 248 — lookup by EntityTypeName (which holds the qualified entity name)
entityTypeID := entityTypeIDMap[es.EntityTypeName]

PublishedEntityType.ExposedName is the OData-facing name (e.g. \"Customers\").
PublishedEntitySet.EntityTypeName is the qualified entity name (e.g. \"OdTest.Customer\", set in astEntityDefToModel at mdl/executor/cmd_odata.go:1544).

These are different values, so the lookup returns \"\". In serializePublishedEntitySet (line 305):

if entityTypeID != \"\" {
    doc[\"EntityTypePointer\"] = idToBsonBinary(entityTypeID)
}

The condition is always false → EntityTypePointer is never written. Studio Pro then can't navigate from EntitySet to its EntityType and NREs.

Reproduction

Run any MDL script that creates a published OData service with at least one publish entity block, then open the project in Studio Pro:

create persistent entity Demo.Customer ( Name: string(200) );

create odata service Demo.CustomerAPI (
  path: '/odata/customers',
  version: '1.0.0',
  ODataVersion: OData4,
  namespace: 'Demo.Customers'
)
authentication basic
{
  publish entity Demo.Customer as 'Customers' ( ReadMode: source )
  expose (*);
};

The resulting ODataPublish\$EntitySet BSON has no EntityTypePointer field. Confirmed by inspecting mprcontents/**/*.mxunit from a real project — every EntitySet sub-document is missing the field.

Proposed fix

One-line change in sdk/mpr/writer_odata.go:235:

-    entityTypeIDMap[et.ExposedName] = etID
+    entityTypeIDMap[et.Entity] = etID

et.Entity is the qualified entity name (\"OdTest.Customer\"), matching how EntityTypeName is set on the corresponding EntitySet.

Add a test in sdk/mpr/writer_odata_test.go that asserts the EntitySet's EntityTypePointer matches the EntityType's \$ID. The existing TestSerializePublishedODataService covers other fields but not this pointer, which is why the bug landed undetected.

Related

• mxcli#590 — sibling Studio Pro NRE (CallExternalAction.SchemaAction) from the same example file
• mxcli#594 — sibling Studio Pro NRE (ODataRemoteEntitySource.RemoteId) from the same example file
• mxcli#592 — example-file workarounds; this issue is the underlying writer bug

[github-actions]

Issue Triage

Summary:
The serializePublishedODataService function fails to set the EntityTypePointer field on published OData EntitySet documents, causing a NullReferenceException in Studio Pro’s project checker.

Checklist for bug report completeness

Required info	Present?	Details
mxcli version	❌	Not mentioned
Mendix version	❌	Not mentioned
Scenario (what user was trying to do)	✅	MDL script creating a published OData service
Expected output	✅	EntityTypePointer field should be written
Experienced output (error/message/crash)	✅	Stack trace showing NullReferenceException in EntitySet.Check
AI bug report (mxcli diag --bundle or session log)	❌	Not provided

What’s missing:
Please add the mxcli version (output of mxcli --version or commit/build info), the Mendix version of the project you’re processing, and, if possible, an AI bug report (mxcli diag --bundle) or at least the relevant session log. This will help us reproduce and verify the fix.

Thank you for the detailed analysis—once we have those pieces, we can move forward quickly!

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