I am migrating a content import application from Tridion Docs WCF/SOAP  to OpenAPI. I’m having a problem trying to set taxonomy-related metadata values when creating a new object. (POST /v3/DocumentObjects).

WCF accepted taxonomy id values in XML metadata like the following:

<ishfield name="FCUSTOMFIELD1" level="logical" ishvaluetype="id">48720490</ishfield>

I’ve tried a number of REST metadata structures to approximate the same functionality but get either a 400 error or 500 error depending on the json that I send. My latest json below returns a 500 error. What am I doing wrong?

{
"folderId": 35160071,
"fields": [
{
"type": "SetTagFieldValue",
"ishField": {
"name": "FCUSTOMFIELD1",
"level": "version"
},
"value": {
"id": "17574057"
}
},
{
"type": "SetStringFieldValue",
"ishField": {
"name": "FTITLE",
"level": "logical"
},
"value": "Publication map"
},
{
"type": "SetStringFieldValue",
"ishField": {
"name": "FMASTERTYPE",
"level": "logical"
},
"value": "Map"
},
{
"type": "SetStringFieldValue",
"ishField": {
"name": "FSTATUS",
"level": "language"
},
"value": "Draft"
},
{
"type": "SetStringFieldValue",
"ishField": {
"name": "FAUTHOR",
"level": "language"
},
"value": "importTester"
},
{
"type": "SetStringFieldValue",
"ishField": {
"name": "DOC-LANGUAGE",
"level": "language"
},
"value": "en-US"
},
{
"type": "SetStringFieldValue",
"ishField": {
"name": "VERSION",
"level": "version"
},
"value": "1"
},
{
"type": "SetObjectFieldValue",
"ishField": {
"name": "EDT",
"level": "none"
},
"value": {
"type": "SetElectronicDocumentType",
"id": "EDTXML"
}
},
{
"type": "SetStringFieldValue",
"ishField": {
"name": "FMAPID",
"level": "logical"
},
"value": "GUID-xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
}
]
}