Remove legacy mapping code. (#29224)

Some features have been deprecated since `6.0` like the `_parent` field or the
ability to have multiple types per index. This allows to remove quite some
code, which in-turn will hopefully make it easier to proceed with the removal
of types.

client/rest-high-level/src/main/java/org/elasticsearch/client/Request.java

@@ -136,7 +136,6 @@ static Request delete(DeleteRequest deleteRequest) {
 
         Params parameters = Params.builder();
         parameters.withRouting(deleteRequest.routing());
-        parameters.withParent(deleteRequest.parent());
         parameters.withTimeout(deleteRequest.timeout());
         parameters.withVersion(deleteRequest.version());
         parameters.withVersionType(deleteRequest.versionType());
@@ -315,9 +314,6 @@ static Request bulk(BulkRequest bulkRequest) throws IOException {
                     if (Strings.hasLength(request.routing())) {
                         metadata.field("routing", request.routing());
                     }
-                    if (Strings.hasLength(request.parent())) {
-                        metadata.field("parent", request.parent());
-                    }
                     if (request.version() != Versions.MATCH_ANY) {
                         metadata.field("version", request.version());
                     }
@@ -394,7 +390,6 @@ static Request get(GetRequest getRequest) {
         Params parameters = Params.builder();
         parameters.withPreference(getRequest.preference());
         parameters.withRouting(getRequest.routing());
-        parameters.withParent(getRequest.parent());
         parameters.withRefresh(getRequest.refresh());
         parameters.withRealtime(getRequest.realtime());
         parameters.withStoredFields(getRequest.storedFields());
@@ -422,7 +417,6 @@ static Request index(IndexRequest indexRequest) {
 
         Params parameters = Params.builder();
         parameters.withRouting(indexRequest.routing());
-        parameters.withParent(indexRequest.parent());
         parameters.withTimeout(indexRequest.timeout());
         parameters.withVersion(indexRequest.version());
         parameters.withVersionType(indexRequest.versionType());
@@ -446,7 +440,6 @@ static Request update(UpdateRequest updateRequest) throws IOException {
 
         Params parameters = Params.builder();
         parameters.withRouting(updateRequest.routing());
-        parameters.withParent(updateRequest.parent());
         parameters.withTimeout(updateRequest.timeout());
         parameters.withRefreshPolicy(updateRequest.getRefreshPolicy());
         parameters.withWaitForActiveShards(updateRequest.waitForActiveShards());
@@ -711,10 +704,6 @@ Params withMasterTimeout(TimeValue masterTimeout) {
             return putParam("master_timeout", masterTimeout);
         }
 
-        Params withParent(String parent) {
-            return putParam("parent", parent);
-        }
-
         Params withPipeline(String pipeline) {
             return putParam("pipeline", pipeline);
         }

client/rest-high-level/src/test/java/org/elasticsearch/client/CrudIT.java

@@ -362,19 +362,6 @@ public void testIndex() throws IOException {
                          "version conflict, current version [2] is different than the one provided [5]]", exception.getMessage());
             assertEquals("index", exception.getMetadata("es.index").get(0));
         }
-        {
-            ElasticsearchStatusException exception = expectThrows(ElasticsearchStatusException.class, () -> {
-                IndexRequest indexRequest = new IndexRequest("index", "type", "missing_parent");
-                indexRequest.source(XContentBuilder.builder(xContentType.xContent()).startObject().field("field", "test").endObject());
-                indexRequest.parent("missing");
-
-                execute(indexRequest, highLevelClient()::index, highLevelClient()::indexAsync);
-            });
-
-            assertEquals(RestStatus.BAD_REQUEST, exception.status());
-            assertEquals("Elasticsearch exception [type=illegal_argument_exception, " +
-                         "reason=can't specify parent if no parent field has been configured]", exception.getMessage());
-        }
         {
             ElasticsearchStatusException exception = expectThrows(ElasticsearchStatusException.class, () -> {
                 IndexRequest indexRequest = new IndexRequest("index", "type", "missing_pipeline");
@@ -456,22 +443,6 @@ public void testUpdate() throws IOException {
             assertEquals("Elasticsearch exception [type=version_conflict_engine_exception, reason=[type][id]: version conflict, " +
                             "current version [2] is different than the one provided [1]]", exception.getMessage());
         }
-        {
-            ElasticsearchStatusException exception = expectThrows(ElasticsearchStatusException.class, () -> {
-                UpdateRequest updateRequest = new UpdateRequest("index", "type", "id");
-                updateRequest.doc(singletonMap("field", "updated"), randomFrom(XContentType.values()));
-                if (randomBoolean()) {
-                    updateRequest.parent("missing");
-                } else {
-                    updateRequest.routing("missing");
-                }
-                execute(updateRequest, highLevelClient()::update, highLevelClient()::updateAsync);
-            });
-
-            assertEquals(RestStatus.NOT_FOUND, exception.status());
-            assertEquals("Elasticsearch exception [type=document_missing_exception, reason=[type][id]: document missing]",
-                    exception.getMessage());
-        }
         {
             IndexRequest indexRequest = new IndexRequest("index", "type", "with_script");
             indexRequest.source(singletonMap("counter", 12));

client/rest-high-level/src/test/java/org/elasticsearch/client/RequestTests.java

@@ -209,9 +209,6 @@ public void testMultiGet() throws IOException {
             if (randomBoolean()) {
                 item.routing(randomAlphaOfLength(4));
             }
-            if (randomBoolean()) {
-                item.parent(randomAlphaOfLength(4));
-            }
             if (randomBoolean()) {
                 item.storedFields(generateRandomStringArray(16, 8, false));
             }
@@ -253,11 +250,6 @@ public void testDelete() {
                 deleteRequest.routing(routing);
                 expectedParams.put("routing", routing);
             }
-            if (randomBoolean()) {
-                String parent = randomAlphaOfLengthBetween(3, 10);
-                deleteRequest.parent(parent);
-                expectedParams.put("parent", parent);
-            }
         }
 
         Request request = Request.delete(deleteRequest);
@@ -525,11 +517,6 @@ public void testIndex() throws IOException {
                 indexRequest.routing(routing);
                 expectedParams.put("routing", routing);
             }
-            if (randomBoolean()) {
-                String parent = randomAlphaOfLengthBetween(3, 10);
-                indexRequest.parent(parent);
-                expectedParams.put("parent", parent);
-            }
             if (randomBoolean()) {
                 String pipeline = randomAlphaOfLengthBetween(3, 10);
                 indexRequest.setPipeline(pipeline);
@@ -732,11 +719,6 @@ public void testUpdate() throws IOException {
             updateRequest.routing(routing);
             expectedParams.put("routing", routing);
         }
-        if (randomBoolean()) {
-            String parent = randomAlphaOfLengthBetween(3, 10);
-            updateRequest.parent(parent);
-            expectedParams.put("parent", parent);
-        }
         if (randomBoolean()) {
             String timeout = randomTimeValue();
             updateRequest.timeout(timeout);
@@ -840,15 +822,9 @@ public void testBulk() throws IOException {
                 if (randomBoolean()) {
                     indexRequest.setPipeline(randomAlphaOfLength(5));
                 }
-                if (randomBoolean()) {
-                    indexRequest.parent(randomAlphaOfLength(5));
-                }
             } else if (opType == DocWriteRequest.OpType.CREATE) {
                 IndexRequest createRequest = new IndexRequest(index, type, id).source(source, xContentType).create(true);
                 docWriteRequest = createRequest;
-                if (randomBoolean()) {
-                    createRequest.parent(randomAlphaOfLength(5));
-                }
             } else if (opType == DocWriteRequest.OpType.UPDATE) {
                 final UpdateRequest updateRequest = new UpdateRequest(index, type, id).doc(new IndexRequest().source(source, xContentType));
                 docWriteRequest = updateRequest;
@@ -858,9 +834,6 @@ public void testBulk() throws IOException {
                 if (randomBoolean()) {
                     randomizeFetchSourceContextParams(updateRequest::fetchSource, new HashMap<>());
                 }
-                if (randomBoolean()) {
-                    updateRequest.parent(randomAlphaOfLength(5));
-                }
             } else if (opType == DocWriteRequest.OpType.DELETE) {
                 docWriteRequest = new DeleteRequest(index, type, id);
             } else {
@@ -902,7 +875,6 @@ public void testBulk() throws IOException {
             assertEquals(originalRequest.type(), parsedRequest.type());
             assertEquals(originalRequest.id(), parsedRequest.id());
             assertEquals(originalRequest.routing(), parsedRequest.routing());
-            assertEquals(originalRequest.parent(), parsedRequest.parent());
             assertEquals(originalRequest.version(), parsedRequest.version());
             assertEquals(originalRequest.versionType(), parsedRequest.versionType());
 

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/CRUDDocumentationIT.java

@@ -186,9 +186,6 @@ public void testIndex() throws Exception {
             // tag::index-request-routing
             request.routing("routing"); // <1>
             // end::index-request-routing
-            // tag::index-request-parent
-            request.parent("parent"); // <1>
-            // end::index-request-parent
             // tag::index-request-timeout
             request.timeout(TimeValue.timeValueSeconds(1)); // <1>
             request.timeout("1s"); // <2>
@@ -475,9 +472,6 @@ public void testUpdate() throws Exception {
             // tag::update-request-routing
             request.routing("routing"); // <1>
             // end::update-request-routing
-            // tag::update-request-parent
-            request.parent("parent"); // <1>
-            // end::update-request-parent
             // tag::update-request-timeout
             request.timeout(TimeValue.timeValueSeconds(1)); // <1>
             request.timeout("1s"); // <2>
@@ -583,9 +577,6 @@ public void testDelete() throws Exception {
             // tag::delete-request-routing
             request.routing("routing"); // <1>
             // end::delete-request-routing
-            // tag::delete-request-parent
-            request.parent("parent"); // <1>
-            // end::delete-request-parent
             // tag::delete-request-timeout
             request.timeout(TimeValue.timeValueMinutes(2)); // <1>
             request.timeout("2m"); // <2>
@@ -869,9 +860,6 @@ public void testGet() throws Exception {
             //tag::get-request-routing
             request.routing("routing"); // <1>
             //end::get-request-routing
-            //tag::get-request-parent
-            request.parent("parent"); // <1>
-            //end::get-request-parent
             //tag::get-request-preference
             request.preference("preference"); // <1>
             //end::get-request-preference
@@ -1122,8 +1110,6 @@ public void testMultiGet() throws Exception {
             // tag::multi-get-request-item-extras
             request.add(new MultiGetRequest.Item("index", "type", "with_routing")
                 .routing("some_routing"));          // <1>
-            request.add(new MultiGetRequest.Item("index", "type", "with_parent")
-                .parent("some_parent"));            // <2>
             request.add(new MultiGetRequest.Item("index", "type", "with_version")
                 .versionType(VersionType.EXTERNAL)  // <3>
                 .version(10123L));                  // <4>

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/SearchDocumentationIT.java

@@ -131,7 +131,7 @@ public void testSearch() throws Exception {
 
             // tag::search-source-sorting
             sourceBuilder.sort(new ScoreSortBuilder().order(SortOrder.DESC)); // <1>
-            sourceBuilder.sort(new FieldSortBuilder("_uid").order(SortOrder.ASC));  // <2>
+            sourceBuilder.sort(new FieldSortBuilder("_id").order(SortOrder.ASC));  // <2>
             // end::search-source-sorting
 
             // tag::search-source-filtering-off

docs/java-rest/high-level/document/delete.asciidoc

@@ -23,12 +23,6 @@ include-tagged::{doc-tests}/CRUDDocumentationIT.java[delete-request-routing]
 --------------------------------------------------
 <1> Routing value
 
-["source","java",subs="attributes,callouts,macros"]
---------------------------------------------------
-include-tagged::{doc-tests}/CRUDDocumentationIT.java[delete-request-parent]
---------------------------------------------------
-<1> Parent value
-
 ["source","java",subs="attributes,callouts,macros"]
 --------------------------------------------------
 include-tagged::{doc-tests}/CRUDDocumentationIT.java[delete-request-timeout]

docs/java-rest/high-level/document/get.asciidoc

@@ -51,12 +51,6 @@ include-tagged::{doc-tests}/CRUDDocumentationIT.java[get-request-routing]
 --------------------------------------------------
 <1> Routing value
 
-["source","java",subs="attributes,callouts,macros"]
---------------------------------------------------
-include-tagged::{doc-tests}/CRUDDocumentationIT.java[get-request-parent]
---------------------------------------------------
-<1> Parent value
-
 ["source","java",subs="attributes,callouts,macros"]
 --------------------------------------------------
 include-tagged::{doc-tests}/CRUDDocumentationIT.java[get-request-preference]

docs/java-rest/high-level/document/index.asciidoc

@@ -49,12 +49,6 @@ include-tagged::{doc-tests}/CRUDDocumentationIT.java[index-request-routing]
 --------------------------------------------------
 <1> Routing value
 
-["source","java",subs="attributes,callouts,macros"]
---------------------------------------------------
-include-tagged::{doc-tests}/CRUDDocumentationIT.java[index-request-parent]
---------------------------------------------------
-<1> Parent value
-
 ["source","java",subs="attributes,callouts,macros"]
 --------------------------------------------------
 include-tagged::{doc-tests}/CRUDDocumentationIT.java[index-request-timeout]

docs/java-rest/high-level/document/update.asciidoc

@@ -93,12 +93,6 @@ include-tagged::{doc-tests}/CRUDDocumentationIT.java[update-request-routing]
 --------------------------------------------------
 <1> Routing value
 
-["source","java",subs="attributes,callouts,macros"]
---------------------------------------------------
-include-tagged::{doc-tests}/CRUDDocumentationIT.java[update-request-parent]
---------------------------------------------------
-<1> Parent value
-
 ["source","java",subs="attributes,callouts,macros"]
 --------------------------------------------------
 include-tagged::{doc-tests}/CRUDDocumentationIT.java[update-request-timeout]

docs/reference/docs/delete-by-query.asciidoc

@@ -492,7 +492,7 @@ Which results in a sensible `total` like this one:
 ==== Automatic slicing
 
 You can also let delete-by-query automatically parallelize using
-<<sliced-scroll>> to slice on `_uid`. Use `slices` to specify the number of
+<<sliced-scroll>> to slice on `_id`. Use `slices` to specify the number of
 slices to use:
 
 [source,js]

docs/reference/docs/update-by-query.asciidoc

@@ -531,7 +531,7 @@ Which results in a sensible `total` like this one:
 ==== Automatic slicing
 
 You can also let update-by-query automatically parallelize using
-<<sliced-scroll>> to slice on `_uid`. Use `slices` to specify the number of
+<<sliced-scroll>> to slice on `_id`. Use `slices` to specify the number of
 slices to use:
 
 [source,js]

docs/reference/how-to/recipes/scoring.asciidoc

@@ -35,9 +35,9 @@ consistent across queries.
 
 This work around has another benefit: when two documents have the same score,
 they will be sorted by their internal Lucene doc id (which is unrelated to the
-`_id` or `_uid`) by default. However these doc ids could be different across
-copies of the same shard. So by always hitting the same shard, we would get
-more consistent ordering of documents that have the same scores.
+`_id`) by default. However these doc ids could be different across copies of
+the same shard. So by always hitting the same shard, we would get more
+consistent ordering of documents that have the same scores.
 
 [float]
 ==== Relevancy looks wrong

docs/reference/mapping/fields.asciidoc

@@ -13,10 +13,6 @@ can be customised when a mapping type is created.
 
     The index to which the document belongs.
 
-<<mapping-uid-field,`_uid`>>::
-
-    A composite field consisting of the `_type` and the `_id`.
-
 <<mapping-type-field,`_type`>>::
 
     The document's <<mapping-type,mapping type>>.

docs/reference/mapping/fields/id-field.asciidoc

@@ -5,10 +5,6 @@ Each document has an `_id` that uniquely identifies it, which is indexed
 so that documents can be looked up either with the <<docs-get,GET API>> or the
 <<query-dsl-ids-query,`ids` query>>.
 
-NOTE: This was not the case with pre-6.0 indices due to the fact that they
-supported multiple types, so the `_type` and `_id` were merged into a composite
-primary key called `_uid`.
-
 The value of the `_id` field is accessible in certain queries (`term`,
 `terms`, `match`, `query_string`, `simple_query_string`).