[SOLR-15018] Atomic update deletes child documents if schema has catch-all ignore field

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 8.6.3
• Component/s: update
• Labels: AtomicUpdate ChildDocuments NestedDocuments
• Assignee: Unassigned
• Reporter: Andreas Hubold
• Created: 25/Nov/20 17:01
• Updated: 13/Feb/21 00:09

Description

Nested child documents disappear when some unrelated fields of a parent document are atomically updated, if the schema contains a catch-all dynamic field to ignore unknown fields like:

<dynamicField name="*" type="ignored" />
<fieldType name="ignored" stored="false" indexed="false" multiValued="true" class="solr.StrField" /> 

DistributedUpdateProcessor#getUpdatedDocument tries to reconstruct the original document, but it does not receive nested documents from RealTimeComponent#getInputDocument. Nested documents are correctly found in the index but get lost when RealTimeGetComponent#toSolrInputDocument creates a SolrInputDocument for it. The problematic code is:

SchemaField sf = schema.getFieldOrNull(fname);
if (sf != null) {
  if ((!sf.hasDocValues() && !sf.stored()) || schema.isCopyFieldTarget(sf)) continue;
} 

The code finds the "ignored" SchemaField as matching field for the nested document name (loaded from nest_path). Because of that they're not added to the SolrInputDocument.