Add patterned_text feature_flag

Author: parkertimmins

x-pack/plugin/logsdb/src/main/java/org/elasticsearch/xpack/logsdb/LogsDBPlugin.java

@@ -106,7 +106,11 @@ public List<ActionPlugin.ActionHandler> getActions() {
 
     @Override
     public Map<String, Mapper.TypeParser> getMappers() {
-        return singletonMap(PatternedTextFieldType.CONTENT_TYPE, PatternedTextFieldMapper.PARSER);
+        if (PatternedTextFieldMapper.PATTERNED_TEXT_MAPPER.isEnabled()) {
+            return singletonMap(PatternedTextFieldType.CONTENT_TYPE, PatternedTextFieldMapper.PARSER);
+        } else {
+            return Map.of();
+        }
     }
 
     protected XPackLicenseState getLicenseState() {

x-pack/plugin/logsdb/src/main/java/org/elasticsearch/xpack/logsdb/patternedtext/PatternedTextFieldMapper.java

@@ -12,6 +12,7 @@
 import org.apache.lucene.document.SortedSetDocValuesField;
 import org.apache.lucene.index.IndexOptions;
 import org.apache.lucene.util.BytesRef;
+import org.elasticsearch.common.util.FeatureFlag;
 import org.elasticsearch.index.IndexVersion;
 import org.elasticsearch.index.analysis.IndexAnalyzers;
 import org.elasticsearch.index.analysis.NamedAnalyzer;
@@ -30,6 +31,8 @@
  */
 public class PatternedTextFieldMapper extends FieldMapper {
 
+    public static final FeatureFlag PATTERNED_TEXT_MAPPER = new FeatureFlag("patterned_text");
+
     public static class Defaults {
         public static final FieldType FIELD_TYPE;