Add delete API to the High Level Rest Client

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

@@ -20,6 +20,7 @@
 package org.elasticsearch.client;
 
 import org.apache.http.HttpEntity;
+import org.elasticsearch.action.delete.DeleteRequest;
 import org.elasticsearch.action.get.GetRequest;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.lucene.uid.Versions;
@@ -67,6 +68,10 @@ static Request get(GetRequest getRequest) {
         return new Request("GET", getEndpoint(getRequest), getParams(getRequest), null);
     }
 
+    static Request delete(DeleteRequest deleteRequest) {
+        return new Request("DELETE", deleteEndpoint(deleteRequest), deleteParams(deleteRequest), null);
+    }
+
     private static Map<String, String> getParams(GetRequest getRequest) {
         Map<String, String> params = new HashMap<>();
         putParam("preference", getRequest.preference(), params);
@@ -102,11 +107,29 @@ private static Map<String, String> getParams(GetRequest getRequest) {
         return Collections.unmodifiableMap(params);
     }
 
+    private static Map<String, String> deleteParams(DeleteRequest deleteRequest) {
+        Map<String, String> params = new HashMap<>();
+        putParam("routing", deleteRequest.routing(), params);
+        putParam("parent", deleteRequest.parent(), params);
+        if (deleteRequest.version() != Versions.MATCH_ANY) {
+            params.put("version", Long.toString(deleteRequest.version()));
+        }
+        if (deleteRequest.versionType() != VersionType.INTERNAL) {
+            params.put("version_type", deleteRequest.versionType().name().toLowerCase(Locale.ROOT));
+        }
+        return Collections.unmodifiableMap(params);
+    }
+
     private static String getEndpoint(GetRequest getRequest) {
         StringJoiner pathJoiner = new StringJoiner("/", "/", "");
         return pathJoiner.add(getRequest.index()).add(getRequest.type()).add(getRequest.id()).toString();
     }
 
+    private static String deleteEndpoint(DeleteRequest deleteRequest) {
+        StringJoiner pathJoiner = new StringJoiner("/", "/", "");
+        return pathJoiner.add(deleteRequest.index()).add(deleteRequest.type()).add(deleteRequest.id()).toString();
+    }
+
     private static void putParam(String key, String value, Map<String, String> params) {
         if (Strings.hasLength(value)) {
             params.put(key, value);

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

@@ -26,6 +26,8 @@
 import org.elasticsearch.action.ActionListener;
 import org.elasticsearch.action.ActionRequest;
 import org.elasticsearch.action.ActionRequestValidationException;
+import org.elasticsearch.action.delete.DeleteRequest;
+import org.elasticsearch.action.delete.DeleteResponse;
 import org.elasticsearch.action.get.GetRequest;
 import org.elasticsearch.action.get.GetResponse;
 import org.elasticsearch.action.main.MainRequest;
@@ -92,6 +94,22 @@ public void existsAsync(GetRequest getRequest, ActionListener<Boolean> listener,
                 Collections.emptySet(), headers);
     }
 
+    /**
+     * Deletes a document by id using the delete api
+     */
+    public DeleteResponse delete(DeleteRequest deleteRequest, Header... headers) throws IOException {
+        return performRequestAndParseEntity(deleteRequest, Request::delete, DeleteResponse::fromXContent, Collections.singleton(404),
+            headers);
+    }
+
+    /**
+     * Asynchronously deletes a document by id using the delete api
+     */
+    public void deleteAsync(DeleteRequest deleteRequest, ActionListener<DeleteResponse> listener, Header... headers) {
+        performRequestAsyncAndParseEntity(deleteRequest, Request::delete, DeleteResponse::fromXContent, listener,
+            Collections.singleton(404), headers);
+    }
+
     private <Req extends ActionRequest, Resp> Resp performRequestAndParseEntity(Req request, Function<Req, Request>  requestConverter,
             CheckedFunction<XContentParser, Resp, IOException> entityParser, Set<Integer> ignores, Header... headers) throws IOException {
         return performRequest(request, requestConverter, (response) -> parseEntity(response.getEntity(), entityParser), ignores, headers);

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

@@ -22,6 +22,9 @@
 import org.apache.http.entity.ContentType;
 import org.apache.http.entity.StringEntity;
 import org.elasticsearch.ElasticsearchException;
+import org.elasticsearch.action.DocWriteResponse;
+import org.elasticsearch.action.delete.DeleteRequest;
+import org.elasticsearch.action.delete.DeleteResponse;
 import org.elasticsearch.action.get.GetRequest;
 import org.elasticsearch.action.get.GetResponse;
 import org.elasticsearch.common.Strings;
@@ -141,4 +144,40 @@ public void testGet() throws IOException {
             assertEquals("value1", sourceAsMap.get("field1"));
         }
     }
+
+    public void testDelete() throws IOException {
+        {
+            DeleteRequest deleteRequest = new DeleteRequest("index", "type", "does_not_exist");
+            DeleteResponse deleteResponse = execute(deleteRequest, highLevelClient()::delete, highLevelClient()::deleteAsync);
+            assertEquals("index", deleteResponse.getIndex());
+            assertEquals("type", deleteResponse.getType());
+            assertEquals("does_not_exist", deleteResponse.getId());
+            assertEquals(DocWriteResponse.Result.NOT_FOUND, deleteResponse.getResult());
+            assertEquals(1, deleteResponse.getVersion());
+        }
+        String document = "{\"field1\":\"value1\",\"field2\":\"value2\"}";
+        StringEntity stringEntity = new StringEntity(document, ContentType.APPLICATION_JSON);
+        Response response = client().performRequest("PUT", "/index/type/id", Collections.singletonMap("refresh", "wait_for"), stringEntity);
+        assertEquals(201, response.getStatusLine().getStatusCode());
+        {
+            DeleteRequest deleteRequest = new DeleteRequest("index", "type", "id").version(2);
+            ElasticsearchException exception = expectThrows(ElasticsearchException.class,
+                () -> execute(deleteRequest, highLevelClient()::delete, highLevelClient()::deleteAsync));
+            assertEquals(RestStatus.CONFLICT, exception.status());
+            assertEquals("Elasticsearch exception [type=version_conflict_engine_exception, " + "reason=[type][id]: " +
+                    "version conflict, current version [1] is different than the one provided [2]]", exception.getMessage());
+            assertEquals("index", exception.getMetadata("es.index").get(0));
+        }
+        {
+            DeleteRequest deleteRequest = new DeleteRequest("index", "type", "id");
+            if (randomBoolean()) {
+                deleteRequest.version(1L);
+            }
+            DeleteResponse deleteResponse = execute(deleteRequest, highLevelClient()::delete, highLevelClient()::deleteAsync);
+            assertEquals("index", deleteResponse.getIndex());
+            assertEquals("type", deleteResponse.getType());
+            assertEquals("id", deleteResponse.getId());
+            assertEquals(DocWriteResponse.Result.DELETED, deleteResponse.getResult());
+        }
+    }
 }