From 4bf8f6f3e9f7e9dafe5b6040c2b3b68b035c1429 Mon Sep 17 00:00:00 2001
From: Mohammed Taha Khan <mohammed.taha.khan@cern.ch>
Date: Wed, 16 Sep 2026 14:45:37 +0200
Subject: [PATCH] fix(harvester): keep shared DOI on the latest version

---
 .../inspire_harvester/transform/splitter.py   | 11 +++++++++
 .../transform/transform_entry.py              |  6 ++++-
 .../inspire_harvester/test_transformer.py     | 24 ++++++++++++++++++-
 3 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/site/cds_rdm/inspire_harvester/transform/splitter.py b/site/cds_rdm/inspire_harvester/transform/splitter.py
index b1286b62..dc8641b8 100644
--- a/site/cds_rdm/inspire_harvester/transform/splitter.py
+++ b/site/cds_rdm/inspire_harvester/transform/splitter.py
@@ -15,6 +15,17 @@ def _is_arxiv(source: str) -> bool:
     return (source or "").lower() in _ARXIV_SOURCES
 
 
+def keep_shared_doi_on_latest(latest_entry, versions):
+    """Leave a DOI used by extra versions on the latest version only."""
+    latest_doi = (latest_entry.get("pids") or {}).get("doi", {}).get("identifier")
+    if not latest_doi:
+        return
+    for version in versions:
+        pids = version.get("pids") or {}
+        if pids.get("doi", {}).get("identifier") == latest_doi:
+            pids.pop("doi", None)
+
+
 class InspireVersionSplitter:
     """Split one INSPIRE record with multiple doc types into two source-filtered sub-records.
 
diff --git a/site/cds_rdm/inspire_harvester/transform/transform_entry.py b/site/cds_rdm/inspire_harvester/transform/transform_entry.py
index 4449a3c0..0f4c2c7b 100644
--- a/site/cds_rdm/inspire_harvester/transform/transform_entry.py
+++ b/site/cds_rdm/inspire_harvester/transform/transform_entry.py
@@ -14,7 +14,10 @@
 from cds_rdm.inspire_harvester.transform.config import mapper_policy
 from cds_rdm.inspire_harvester.transform.context import MetadataSerializationContext
 from cds_rdm.inspire_harvester.transform.resource_types import ResourceTypeDetector
-from cds_rdm.inspire_harvester.transform.splitter import InspireVersionSplitter
+from cds_rdm.inspire_harvester.transform.splitter import (
+    InspireVersionSplitter,
+    keep_shared_doi_on_latest,
+)
 from cds_rdm.inspire_harvester.utils import assert_unique_ids, deep_merge_all
 
 
@@ -106,6 +109,7 @@ def build(self):
         )
 
         versions = self._versions()
+        keep_shared_doi_on_latest(rdm_record, versions)
         return rdm_record, versions, self.cds_id, self.errors
 
 
diff --git a/site/tests/inspire_harvester/test_transformer.py b/site/tests/inspire_harvester/test_transformer.py
index d7103a8a..6365d60e 100644
--- a/site/tests/inspire_harvester/test_transformer.py
+++ b/site/tests/inspire_harvester/test_transformer.py
@@ -37,7 +37,10 @@
     RelatedIdentifiersMapper,
 )
 from cds_rdm.inspire_harvester.transform.resource_types import ResourceType
-from cds_rdm.inspire_harvester.transform.splitter import InspireVersionSplitter
+from cds_rdm.inspire_harvester.transform.splitter import (
+    InspireVersionSplitter,
+    keep_shared_doi_on_latest,
+)
 from cds_rdm.inspire_harvester.transform.transform_entry import Inspire2RDM
 
 
@@ -643,6 +646,25 @@ def test_splitter_creates_one_version_for_duplicate_resource_types(mock_logger):
     policy.build_for.assert_called_once_with(ResourceType.REPORT)
 
 
+def test_keep_shared_doi_on_latest_drops_duplicate_from_extra_versions():
+    """Latest version keeps a shared DOI; extra versions lose it."""
+    journal_doi = {
+        "identifier": "10.1016/j.nima.2022.166874",
+        "provider": "external",
+    }
+    latest = {"pids": {"doi": journal_doi}}
+    note = {"pids": {"doi": dict(journal_doi)}}
+    report = {
+        "pids": {"doi": {"identifier": "10.17181/other", "provider": "datacite"}}
+    }
+
+    keep_shared_doi_on_latest(latest, [note, report])
+
+    assert latest["pids"]["doi"]["identifier"] == journal_doi["identifier"]
+    assert "doi" not in note["pids"]
+    assert report["pids"]["doi"]["identifier"] == "10.17181/other"
+
+
 def test_transform_document_type_unmapped(running_app):
     """Test ResourceTypeDetector with unmapped type."""
     from cds_rdm.inspire_harvester.transform.resource_types import ResourceTypeDetector