Add a delegator in daoconfig

hapi-fhir-jpaserver-api/src/main/java/ca/uhn/fhir/jpa/api/config/DaoConfig.java

@@ -1716,6 +1716,36 @@ public class DaoConfig {
 		this.myModelConfig.setAllowContainsSearches(theAllowContainsSearches);
 	}
 
+	/**
+	 * If enabled, the server will support the use of :mdm search parameter qualifier on Reference Search Parameters.
+	 * This Parameter Qualifier is HAPI-specific, and not defined anywhere in the FHIR specification. Using this qualifier
+	 * will result in an MDM expansion being done on the reference, which will expand the search scope. For example, if Patient/1
+	 * is MDM-matched to Patient/2 and you execute the search:
+	 * Observation?subject:mdm=Patient/1 , you will receive observations for both Patient/1 and Patient/2.
+	 * <p>
+	 * Default is <code>false</code>
+	 * </p>
+	 * @since 5.4.0
+	 */
+	public boolean isAllowMdmExpansion() {
+		return myModelConfig.isAllowMdmExpansion();
+	}
+
+	/**
+	 * If enabled, the server will support the use of :mdm search parameter qualifier on Reference Search Parameters.
+	 * This Parameter Qualifier is HAPI-specific, and not defined anywhere in the FHIR specification. Using this qualifier
+	 * will result in an MDM expansion being done on the reference, which will expand the search scope. For example, if Patient/1
+	 * is MDM-matched to Patient/2 and you execute the search:
+	 * Observation?subject:mdm=Patient/1 , you will receive observations for both Patient/1 and Patient/2.
+	 * <p>
+	 * Default is <code>false</code>
+	 * </p>
+	 * @since 5.4.0
+	 */
+	public void setAllowMdmExpansion(boolean theAllowMdmExpansion) {
+		myModelConfig.setAllowMdmExpansion(theAllowMdmExpansion);
+	}
+
 	/**
 	 * This setting may be used to advise the server that any references found in
 	 * resources that have any of the base URLs given here will be replaced with

hapi-fhir-jpaserver-model/src/main/java/ca/uhn/fhir/jpa/model/entity/ModelConfig.java

@@ -174,6 +174,18 @@ public class ModelConfig {
 	public boolean isAllowMdmExpansion() {
 		return myAllowMdmExpansion;
 	}
+
+	/**
+	 * If enabled, the server will support the use of :mdm search parameter qualifier on Reference Search Parameters.
+	 * This Parameter Qualifier is HAPI-specific, and not defined anywhere in the FHIR specification. Using this qualifier
+	 * will result in an MDM expansion being done on the reference, which will expand the search scope. For example, if Patient/1
+	 * is MDM-matched to Patient/2 and you execute the search:
+	 * Observation?subject:mdm=Patient/1 , you will receive observations for both Patient/1 and Patient/2.
+	 * <p>
+	 * Default is <code>false</code>
+	 * </p>
+	 * @since 5.4.0
+	 */
 	public void setAllowMdmExpansion(boolean theAllowMdmExpansion) {
 		myAllowMdmExpansion = theAllowMdmExpansion;
 	}