How to create a Design Automation workitem with a composite design Revit file with nested references - autodesk-forge

Question

Given the following situation, where "->" is a Xref reference in either overlay or attachment mode:
TOPHOST.rvt -> LINKA.rvt -> LINKA1.rvt
I know that I can use .../:version_id/relationships/refs to retrieve references from TOPHOST.rvt, which includes the reference to LINKA.rvt.
I can repeat this with a query for LINKA.rvt, which will return the reference to LINKA1.rvt.
This way, I can gather all information necessary to create a workitem for design automation, following this guide on how to include links (see "Host RVT file with linked models").
This works for versions that are not marked as isCompositeDesign (not documented in versions/:version_id, but isCompositeDesign is a key in attributes.extension.data with boolean values). For these versions, the .../:version_id/relationships/refs API will return empty data, ie. no references!
This is a huge problem, as in active projects, items are isCompositeDesign=true most of the time.
How can I get the reference information necessary to create a Design Automation workitem in scenarios with composite designs?

Answer 1

Update Apr. 28, 2023
It seems related to one known issue FDM-3977. I will update here once our engineering team gets back.
====================
If your target version urn shows that it's a composite design in its attributes.extension.data.isCompositeDesign like this one, according to Why an RVT model is (sometimes) downloaded as ZIP from BIM 360, then you should get a ZIP file that contains the host and all linked RVTs while downloading the host RVT file via GET buckets/wip.dm.prod/objects/XXXX.rvt. Isn't it what you want?
{
"type": "versions",
"id": "urn:adsk.wipprod:fs.file:vf.UTLEaKw?version=4",
"attributes": {
"name": "test.rvt",
"displayName": "test.rvt",
//...
"versionNumber": 4,
"mimeType": "application/vnd.autodesk.r360",
"storageSize": 111297725,
"fileType": "rvt",
"extension": {
"type": "versions:autodesk.bim360:C4RModel",
"version": "1.1.0",
"schema": {
"href": "https://developer.api.autodesk.com/schema/v1/versions/versions:autodesk.bim360:C4RModel-1.1.0"
},
"data": {
"modelVersion": 3,
"isCompositeDesign": true,
"mimeType": "application/vnd.autodesk.r360",
"compositeParentFile": "test.rvt",
//..
"modelType": "multiuser",
//..
"processState": "PROCESSING_COMPLETE",
"extractionState": "SUCCESS",
"splittingState": "NOT_SPLIT",
"reviewState": "NOT_IN_REVIEW",
"revisionDisplayLabel": "4",
"sourceFileName": "test.rvt",
"conformingStatus": "NONE"
}
}
},
"relationships": {
//...
"storage": {
"data": {
"type": "objects",
"id": "urn:adsk.objects:os.object:wip.dm.prod/XXXX.rvt"
},
"meta": {
"link": {
"href": "https://developer.api.autodesk.com/oss/v2/buckets/wip.dm.prod/objects/XXXX.rvt"
}
}
}
}
}