[fix] add adapter for fix relationfield deserializer

src/redturtle/volto/restapi/deserializer/configure.zcml

@@ -28,6 +28,9 @@
   <!-- convert Link widget value in normalized url -->
   <adapter factory=".dxfields.LinkTextLineFieldDeserializer" />
 
+  <!-- convert related string obj to obj -->
+  <adapter factory=".relationfield.RelationChoiceFieldDeserializer" />
+
 
   <adapter factory=".dxfields.DatetimeFieldDeserializer" />
 

src/redturtle/volto/restapi/deserializer/relationfield.py

@@ -0,0 +1,60 @@
+from plone.dexterity.interfaces import IDexterityContent
+from plone.restapi.deserializer.dxfields import DefaultFieldDeserializer
+from plone.restapi.interfaces import IFieldDeserializer
+from Products.CMFCore.utils import getToolByName
+from redturtle.volto.interfaces import IRedturtleVoltoLayer
+from z3c.relationfield.interfaces import IRelationChoice
+from zope.component import adapter
+from zope.component import getMultiAdapter
+from zope.component import queryUtility
+from zope.interface import implementer
+from zope.intid.interfaces import IIntIds
+
+
+@implementer(IFieldDeserializer)
+@adapter(IRelationChoice, IDexterityContent, IRedturtleVoltoLayer)
+class RelationChoiceFieldDeserializer(DefaultFieldDeserializer):
+    def __call__(self, value):
+        obj = None
+        resolved_by = None
+
+        if isinstance(value, dict):
+            # We are trying to deserialize the output of a serialization
+            # which is enhanced, extract it and put it on the loop again
+            value = value["UID"] if value.get("UID", None) else value["@id"]
+
+        if isinstance(value, int):
+            # Resolve by intid
+            intids = queryUtility(IIntIds)
+            obj = intids.queryObject(value)
+            resolved_by = "intid"
+        elif isinstance(value, str):
+            portal = getMultiAdapter(
+                (self.context, self.request), name="plone_portal_state"
+            ).portal()
+            portal_url = portal.absolute_url()
+            if value.startswith(portal_url):
+                # Resolve by URL
+                obj = portal.restrictedTraverse(value[len(portal_url) + 1 :], None)
+                resolved_by = "URL"
+            elif value.startswith("/"):
+                # Resolve by path
+                obj = portal.restrictedTraverse(value.lstrip("/"), None)
+                resolved_by = "path"
+            else:
+                # Resolve by UID
+                catalog = getToolByName(self.context, "portal_catalog")
+                brain = catalog(UID=value)
+                if brain:
+                    obj = brain[0].getObject()
+                resolved_by = "UID"
+
+        if obj is None:
+            self.request.response.setStatus(400)
+            msg = f"Could not resolve object for {value}"
+            if resolved_by:
+                msg += f" (resolved by {resolved_by})"
+            raise ValueError(msg)
+
+        self.field.validate(obj)
+        return obj