Fixed bug in mapping parsing; added tests

RFS/src/main/java/org/opensearch/migrations/bulkload/transformers/TransformFunctions.java

@@ -10,6 +10,7 @@
 public class TransformFunctions {
     private static final ObjectMapper mapper = new ObjectMapper();
     public static final String MAPPINGS_KEY_STR = "mappings";
+    public static final String PROPERTIES_KEY_STR = "properties";
     public static final String SETTINGS_KEY_STR = "settings";
     public static final String NUMBER_OF_REPLICAS_KEY_STR = "number_of_replicas";
     public static final String INDEX_KEY_STR = "index";
@@ -75,17 +76,21 @@ public static void removeIntermediateMappingsLevels(ObjectNode root) {
              * - [{"doc":{"properties":{"address":{"type":"text"}}}}]
              * - [{"audit_message":{"properties":{"address":{"type":"text"}}}}]
              *
-             * It's not impossible that the intermediate key is not present, in which case we should just extract the mappings:
+             * It's also possible for this list to be empty, in which case we should set the mappings to an empty node.
+             *
+             * Finally, it may be possible that the intermediate key is not present, in which case we should just extract the mappings:
              * - [{"properties":{"address":{"type":"text"}}}]
              */
             if (val instanceof ArrayNode) {
                 ArrayNode mappingsList = (ArrayNode) val;
-                if (mappingsList.size() != 1) {
+                if (mappingsList.size() > 1) {
                     throw new IllegalArgumentException("Mappings list contains more than one member; this is unexpected: " + val.toString());
+                } else if (mappingsList.size() == 1) {
+                    ObjectNode actualMappingsRoot = (ObjectNode) mappingsList.get(0);
+                    root.set(MAPPINGS_KEY_STR, getMappingsFromBeneathIntermediate(actualMappingsRoot));
+                } else {
+                    root.set(MAPPINGS_KEY_STR, mapper.createObjectNode());
                 }
-                ObjectNode actualMappingsRoot = (ObjectNode) mappingsList.get(0);
-
-                root.set(MAPPINGS_KEY_STR, getMappingsFromBeneathIntermediate(actualMappingsRoot));
             }
 
             /**
@@ -113,9 +118,9 @@ else if (val instanceof ObjectNode) {
      * it regardless of what it is named.
      */
     public static ObjectNode getMappingsFromBeneathIntermediate(ObjectNode mappingsRoot) {
-        if (mappingsRoot.has("properties")) {
+        if (mappingsRoot.has(PROPERTIES_KEY_STR)) {
             return mappingsRoot;
-        } else if (!mappingsRoot.has("properties")) {
+        } else if (!mappingsRoot.has(PROPERTIES_KEY_STR)) {
             return (ObjectNode) mappingsRoot.get(mappingsRoot.fieldNames().next()).deepCopy();
         }
 

RFS/src/test/java/org/opensearch/migrations/bulkload/transformers/TransformFunctionsTest.java

@@ -0,0 +1,98 @@
+package org.opensearch.migrations.bulkload.transformers;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.junit.jupiter.api.Test;
+
+import lombok.extern.slf4j.Slf4j;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+@Slf4j
+public class TransformFunctionsTest {
+
+    @Test
+    public void removeIntermediateMappingsLevels_AsExpected() throws Exception {
+        // Extract from {"mappings":[{"_doc":{"properties":{"address":{"type":"text"}}}}])
+        ObjectNode testNode1 = new ObjectMapper().createObjectNode();
+        ArrayNode mappingsNode1 = new ObjectMapper().createArrayNode();
+        ObjectNode docNode1 = new ObjectMapper().createObjectNode();
+        ObjectNode propertiesNode1 = new ObjectMapper().createObjectNode();
+        ObjectNode addressNode1 = new ObjectMapper().createObjectNode();
+        addressNode1.put("type", "text");
+        propertiesNode1.set("address", addressNode1);
+        docNode1.set(TransformFunctions.PROPERTIES_KEY_STR, propertiesNode1);
+        ObjectNode intermediateNode1 = new ObjectMapper().createObjectNode();
+        intermediateNode1.set("_doc", docNode1);
+        mappingsNode1.add(intermediateNode1);
+        testNode1.set(TransformFunctions.MAPPINGS_KEY_STR, mappingsNode1);
+
+        TransformFunctions.removeIntermediateMappingsLevels(testNode1);
+        assertEquals(docNode1.toString(), testNode1.get(TransformFunctions.MAPPINGS_KEY_STR).toString());
+
+        // Extract from {"mappings":[{"properties":{"address":{"type":"text"}}}])
+        ObjectNode testNode2 = new ObjectMapper().createObjectNode();
+        ArrayNode mappingsNode2 = new ObjectMapper().createArrayNode();
+        ObjectNode propertiesNode2 = new ObjectMapper().createObjectNode();
+        ObjectNode addressNode2 = new ObjectMapper().createObjectNode();
+        addressNode2.put("type", "text");
+        propertiesNode2.set("address", addressNode2);
+        ObjectNode intermediateNode2 = new ObjectMapper().createObjectNode();
+        intermediateNode2.set(TransformFunctions.PROPERTIES_KEY_STR, propertiesNode2);
+        mappingsNode2.add(intermediateNode2);
+        testNode2.set(TransformFunctions.MAPPINGS_KEY_STR, mappingsNode2);
+
+        TransformFunctions.removeIntermediateMappingsLevels(testNode2);
+        assertEquals(intermediateNode2.toString(), testNode2.get(TransformFunctions.MAPPINGS_KEY_STR).toString());
+
+        // Extract from {"mappings":[])
+        ObjectNode testNode3 = new ObjectMapper().createObjectNode();
+        ArrayNode mappingsNode3 = new ObjectMapper().createArrayNode();
+        testNode3.set(TransformFunctions.MAPPINGS_KEY_STR, mappingsNode3);
+
+        TransformFunctions.removeIntermediateMappingsLevels(testNode3);
+        assertEquals(new ObjectMapper().createObjectNode().toString(), testNode3.get(TransformFunctions.MAPPINGS_KEY_STR).toString());
+    }
+
+    @Test
+    public void getMappingsFromBeneathIntermediate_AsExpected() throws Exception {
+        // Extract from {"_doc":{"properties":{"address":{"type":"text"}}}}
+        ObjectNode testNode1 = new ObjectMapper().createObjectNode();
+        ObjectNode docNode1 = new ObjectMapper().createObjectNode();
+        ObjectNode propertiesNode1 = new ObjectMapper().createObjectNode();
+        ObjectNode addressNode1 = new ObjectMapper().createObjectNode();
+        addressNode1.put("type", "text");
+        propertiesNode1.set("address", addressNode1);
+        docNode1.set(TransformFunctions.PROPERTIES_KEY_STR, propertiesNode1);
+        testNode1.set("_doc", docNode1);
+
+        ObjectNode result1 = TransformFunctions.getMappingsFromBeneathIntermediate(testNode1);
+        assertEquals(docNode1.toString(), result1.toString());
+
+        // Extract from {"arbitrary_type":{"properties":{"address":{"type":"text"}}}}
+        ObjectNode testNode2 = new ObjectMapper().createObjectNode();
+        ObjectNode docNode2 = new ObjectMapper().createObjectNode();
+        ObjectNode propertiesNode2 = new ObjectMapper().createObjectNode();
+        ObjectNode addressNode2 = new ObjectMapper().createObjectNode();
+        addressNode2.put("type", "text");
+        propertiesNode2.set("address", addressNode2);
+        docNode2.set(TransformFunctions.PROPERTIES_KEY_STR, propertiesNode2);
+        testNode2.set("arbitrary_type", docNode2);
+
+        ObjectNode result2 = TransformFunctions.getMappingsFromBeneathIntermediate(testNode2);
+        assertEquals(docNode2.toString(), result2.toString());
+
+        // Extract from {"properties":{"address":{"type":"text"}}
+        ObjectNode testNode3 = new ObjectMapper().createObjectNode();
+        ObjectNode propertiesNode3 = new ObjectMapper().createObjectNode();
+        ObjectNode addressNode3 = new ObjectMapper().createObjectNode();
+        addressNode3.put("type", "text");
+        propertiesNode3.set("address", addressNode3);
+        testNode3.set(TransformFunctions.PROPERTIES_KEY_STR, propertiesNode3);
+
+        ObjectNode result3 = TransformFunctions.getMappingsFromBeneathIntermediate(testNode3);
+        assertEquals(testNode3.toString(), result3.toString());
+    }
+
+}

RFS/src/test/java/org/opensearch/migrations/bulkload/transformers/Transformer_ES_7_10_OS_2_11Test.java

@@ -59,10 +59,22 @@ public void transformIndexMetadata_AsExpected() throws Exception {
         IndexMetadata transformedIndexFwc = transformer.transformIndexMetadata(indexMetadataFwc);
         IndexMetadataData_OS_2_11 finalIndexFwc =new IndexMetadataData_OS_2_11(transformedIndexFwc.getRawJson(), transformedIndexFwc.getId(), transformedIndexFwc.getName());
 
-        String expectedIndexBwc = "{\"version\":3,\"mapping_version\":1,\"settings_version\":1,\"aliases_version\":1,\"routing_num_shards\":1024,\"state\":\"open\",\"settings\":{\"creation_date\":\"1727285787498\",\"number_of_replicas\":1,\"number_of_shards\":\"1\",\"provided_name\":\"bwc_index_1\",\"uuid\":\"P4PDS4fFSECIprHxpKSoiQ\",\"version\":{\"created\":\"7100299\"}},\"mappings\":{\"properties\":{\"content\":{\"type\":\"text\"},\"title\":{\"type\":\"text\"}}},\"aliases\":{\"bwc_alias\":{}},\"primary_terms\":[1],\"in_sync_allocations\":{\"0\":[\"0M-gMXkNQFC02lnWJN4BVQ\"]},\"rollover_info\":{},\"system\":false}";
-        String expectedIndexFwc = "{\"version\":3,\"mapping_version\":1,\"settings_version\":1,\"aliases_version\":1,\"routing_num_shards\":1024,\"state\":\"open\",\"settings\":{\"creation_date\":\"1727285787822\",\"number_of_replicas\":1,\"number_of_shards\":\"1\",\"provided_name\":\"fwc_index_1\",\"uuid\":\"riC1gLlrR2eh_uAh9Zdpiw\",\"version\":{\"created\":\"7100299\"}},\"mappings\":{\"properties\":{\"content\":{\"type\":\"text\"},\"title\":{\"type\":\"text\"}}},\"aliases\":{\"fwc_alias\":{}},\"primary_terms\":[1],\"in_sync_allocations\":{\"0\":[\"8sKrVCEaSxy4yP3cx8kcYQ\"]},\"rollover_info\":{},\"system\":false}";
+        IndexMetadata indexMetadataNoMappingNoDocs = sourceResourceProvider.getIndexMetadata().fromRepo(snapshot.name, "no_mappings_no_docs");
+        IndexMetadata transformedIndexNoMappingNoDocs = transformer.transformIndexMetadata(indexMetadataNoMappingNoDocs);
+        IndexMetadataData_OS_2_11 finalIndexNoMappingNoDocs = new IndexMetadataData_OS_2_11(transformedIndexNoMappingNoDocs.getRawJson(), transformedIndexNoMappingNoDocs.getId(), transformedIndexNoMappingNoDocs.getName());
+
+        IndexMetadata indexMetadataEmptyMappingNoDocs = sourceResourceProvider.getIndexMetadata().fromRepo(snapshot.name, "empty_mappings_no_docs");
+        IndexMetadata transformedIndexEmptyMappingNoDocs = transformer.transformIndexMetadata(indexMetadataEmptyMappingNoDocs);
+        IndexMetadataData_OS_2_11 finalIndexEmptyMappingNoDocs = new IndexMetadataData_OS_2_11(transformedIndexEmptyMappingNoDocs.getRawJson(), transformedIndexEmptyMappingNoDocs.getId(), transformedIndexEmptyMappingNoDocs.getName());
+
+        String expectedIndexBwc = "{\"version\":3,\"mapping_version\":1,\"settings_version\":1,\"aliases_version\":1,\"routing_num_shards\":1024,\"state\":\"open\",\"settings\":{\"creation_date\":\"1727459371883\",\"number_of_replicas\":1,\"number_of_shards\":\"1\",\"provided_name\":\"bwc_index_1\",\"uuid\":\"tBmFXxGhTeiDlznQiKfNCA\",\"version\":{\"created\":\"7100299\"}},\"mappings\":{\"properties\":{\"content\":{\"type\":\"text\"},\"title\":{\"type\":\"text\"}}},\"aliases\":{\"bwc_alias\":{}},\"primary_terms\":[1],\"in_sync_allocations\":{\"0\":[\"jSYEePXYTka3EJ0vvdPGJA\"]},\"rollover_info\":{},\"system\":false}";
+        String expectedIndexFwc = "{\"version\":3,\"mapping_version\":1,\"settings_version\":1,\"aliases_version\":1,\"routing_num_shards\":1024,\"state\":\"open\",\"settings\":{\"creation_date\":\"1727459372123\",\"number_of_replicas\":1,\"number_of_shards\":\"1\",\"provided_name\":\"fwc_index_1\",\"uuid\":\"BI3xMNgnRe6HldftNpfxzQ\",\"version\":{\"created\":\"7100299\"}},\"mappings\":{\"properties\":{\"content\":{\"type\":\"text\"},\"title\":{\"type\":\"text\"}}},\"aliases\":{\"fwc_alias\":{}},\"primary_terms\":[1],\"in_sync_allocations\":{\"0\":[\"SvHX-4xPTZWt0sYMTiFGYw\"]},\"rollover_info\":{},\"system\":false}";
+        String expectedIndexNoMappingNoDocs = "{\"version\":3,\"mapping_version\":1,\"settings_version\":1,\"aliases_version\":1,\"routing_num_shards\":1024,\"state\":\"open\",\"settings\":{\"creation_date\":\"1727459372205\",\"number_of_replicas\":1,\"number_of_shards\":\"1\",\"provided_name\":\"no_mappings_no_docs\",\"uuid\":\"S0lxKX7vSLS7jzquAnNzdg\",\"version\":{\"created\":\"7100299\"}},\"mappings\":{},\"aliases\":{},\"primary_terms\":[1],\"in_sync_allocations\":{\"0\":[\"McFl7a21QZKeB7HLHo6eMQ\"]},\"rollover_info\":{},\"system\":false}";
+        String expectedIndexEmptyMappingNoDocs = "{\"version\":3,\"mapping_version\":1,\"settings_version\":1,\"aliases_version\":1,\"routing_num_shards\":1024,\"state\":\"open\",\"settings\":{\"creation_date\":\"1727459372264\",\"number_of_replicas\":1,\"number_of_shards\":\"1\",\"provided_name\":\"empty_mappings_no_docs\",\"uuid\":\"ndSIWVDSQpuC8xY2DieX7g\",\"version\":{\"created\":\"7100299\"}},\"mappings\":{},\"aliases\":{},\"primary_terms\":[1],\"in_sync_allocations\":{\"0\":[\"yr1xkacYT42MjPGjAzQhHg\"]},\"rollover_info\":{},\"system\":false}";
 
         assertEquals(expectedIndexBwc, finalIndexBwc.getRawJson().toString());
         assertEquals(expectedIndexFwc, finalIndexFwc.getRawJson().toString());
+        assertEquals(expectedIndexNoMappingNoDocs, finalIndexNoMappingNoDocs.getRawJson().toString());
+        assertEquals(expectedIndexEmptyMappingNoDocs, finalIndexEmptyMappingNoDocs.getRawJson().toString());
     }
 }

RFS/test-resources/inventory.md

@@ -345,7 +345,7 @@ curl -X PUT "localhost:19200/test_updates_deletes" -H "Content-Type: application
 ```
 
 #### ES_7_10_BWC_Check
-An Elastic 7.10 snapshot repo designed to exercise backwards compatibility across a couple different features.  It contains two indices; one is created using pre-ES 7.8 templates and pre-ES 7.0 type declarations, and the other is created using forward-compatible index/component templates and no type declarations. Both indices contain a single document.
+An Elastic 7.10 snapshot repo designed to exercise backwards compatibility across a couple different features.  It contains two indices; one is created using pre-ES 7.8 templates and pre-ES 7.0 type declarations, and the other is created using forward-compatible index/component templates and no type declarations. Both indices contain a single document.  It also contains two indices with either no mappings or an empty mapping entry and no documents; this exercises an edge case where there will be a mappings entry in the snapshot with no contents.
 
 ```
 curl -X PUT "localhost:19200/_template/bwc_template?include_type_name=true" -H "Content-Type: application/json" -d '
@@ -426,12 +426,36 @@ curl -X PUT "localhost:19200/_index_template/fwc_template" -H "Content-Type: app
 
 curl -X PUT "localhost:19200/fwc_index_1" -H "Content-Type: application/json"
 
-curl -X PUT "localhost:19200/fwc_alias/_doc/bwc_doc" -H "Content-Type: application/json" -d '
+curl -X PUT "localhost:19200/fwc_alias/_doc/fwc_doc" -H "Content-Type: application/json" -d '
 {
   "title": "This is a doc in a forward compatible index",
   "content": "Life, the Universe, and Everything"
 }'
 
+curl -X PUT "localhost:19200/no_mappings_no_docs" -H "Content-Type: application/json" -d '
+{
+  "settings": {
+    "index": {
+      "number_of_shards": 1,
+      "number_of_replicas": 0
+    }
+  }
+}'
+
+curl -X PUT "localhost:19200/empty_mappings_no_docs" -H "Content-Type: application/json" -d '
+{
+  "settings": {
+    "index": {
+      "number_of_shards": 1,
+      "number_of_replicas": 0
+    }
+  },
+  "mappings": {
+    "properties":{
+    }
+  }
+}'
+
 curl -X PUT "localhost:19200/_snapshot/test_repository" -H "Content-Type: application/json" -d '{
   "type": "fs",
   "settings": {
@@ -441,9 +465,8 @@ curl -X PUT "localhost:19200/_snapshot/test_repository" -H "Content-Type: applic
 }'
 
 curl -X PUT "localhost:19200/_snapshot/test_repository/rfs-snapshot" -H "Content-Type: application/json" -d '{
-  "indices": "bwc_index_1,fwc_index_1",
+  "indices": "bwc_index_1,fwc_index_1,no_mappings_no_docs,empty_mappings_no_docs",
   "ignore_unavailable": true,
   "include_global_state": true
 }'
-
 ```

RFS/test-resources/snapshots/ES_7_10_BWC_Check/index-0

@@ -1 +1 @@
-{"snapshots":[{"name":"rfs-snapshot","uuid":"rNzQqxl5Qrm99ZzB44Yz0w","state":1,"index_metadata_lookup":{"rtO3hIcQREynKwRVke75sQ":"P4PDS4fFSECIprHxpKSoiQ-_na_-1-1-1","6f5_qLyfQu-MKqe5IEJGuQ":"riC1gLlrR2eh_uAh9Zdpiw-_na_-1-1-1"},"version":"7.10.2"}],"indices":{"bwc_index_1":{"id":"rtO3hIcQREynKwRVke75sQ","snapshots":["rNzQqxl5Qrm99ZzB44Yz0w"],"shard_generations":["OSYnb8w3SKmTqQ_p7m84JA"]},"fwc_index_1":{"id":"6f5_qLyfQu-MKqe5IEJGuQ","snapshots":["rNzQqxl5Qrm99ZzB44Yz0w"],"shard_generations":["73ZKrS4iTc6nKzY0E4kC1w"]}},"min_version":"7.9.0","index_metadata_identifiers":{"riC1gLlrR2eh_uAh9Zdpiw-_na_-1-1-1":"AzJBKpIBKBXpMe1tfd-g","P4PDS4fFSECIprHxpKSoiQ-_na_-1-1-1":"AjJBKpIBKBXpMe1tfd-g"}}
+{"snapshots":[{"name":"rfs-snapshot","uuid":"KhcpVj8aRMek0oLMUSPHeg","state":1,"index_metadata_lookup":{"zUFSBaZgSdKCPAS2xEfCww":"ndSIWVDSQpuC8xY2DieX7g-_na_-1-1-1","s_FgCb4gREmddVPRW-EtWw":"BI3xMNgnRe6HldftNpfxzQ-_na_-1-1-1","a5ONDmS2RmmN1GEZMRCJRg":"S0lxKX7vSLS7jzquAnNzdg-_na_-1-1-1","0edrmuSPR1CIr2B6BZbMJA":"tBmFXxGhTeiDlznQiKfNCA-_na_-1-1-1"},"version":"7.10.2"}],"indices":{"empty_mappings_no_docs":{"id":"zUFSBaZgSdKCPAS2xEfCww","snapshots":["KhcpVj8aRMek0oLMUSPHeg"],"shard_generations":["C7dK_wyqSUuDyKkefOXUUQ"]},"bwc_index_1":{"id":"0edrmuSPR1CIr2B6BZbMJA","snapshots":["KhcpVj8aRMek0oLMUSPHeg"],"shard_generations":["tGRrEPUKTuWK_eyviXSHvg"]},"fwc_index_1":{"id":"s_FgCb4gREmddVPRW-EtWw","snapshots":["KhcpVj8aRMek0oLMUSPHeg"],"shard_generations":["yaxW_gAlTNqirWlIIoil8A"]},"no_mappings_no_docs":{"id":"a5ONDmS2RmmN1GEZMRCJRg","snapshots":["KhcpVj8aRMek0oLMUSPHeg"],"shard_generations":["cbs2bGwwSy66JeQOO9vNbQ"]}},"min_version":"7.9.0","index_metadata_identifiers":{"ndSIWVDSQpuC8xY2DieX7g-_na_-1-1-1":"3liaNJIBxXZFvc_xLY-F","S0lxKX7vSLS7jzquAnNzdg-_na_-1-1-1":"31iaNJIBxXZFvc_xLY-F","BI3xMNgnRe6HldftNpfxzQ-_na_-1-1-1":"3ViaNJIBxXZFvc_xLY-F","tBmFXxGhTeiDlznQiKfNCA-_na_-1-1-1":"4FiaNJIBxXZFvc_xLY-F"}}