Deprecate support for first line empty in msearch API

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

@@ -27,6 +27,7 @@
 import org.apache.http.client.methods.HttpPut;
 import org.apache.http.nio.entity.NByteArrayEntity;
 import org.apache.http.util.EntityUtils;
+import org.apache.logging.log4j.LogManager;
 import org.elasticsearch.action.DocWriteRequest;
 import org.elasticsearch.action.admin.cluster.storedscripts.DeleteStoredScriptRequest;
 import org.elasticsearch.action.admin.cluster.storedscripts.GetStoredScriptRequest;
@@ -62,6 +63,7 @@
 import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.collect.Tuple;
 import org.elasticsearch.common.io.Streams;
+import org.elasticsearch.common.logging.DeprecationLogger;
 import org.elasticsearch.common.lucene.uid.Versions;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.common.xcontent.ToXContent;
@@ -132,6 +134,10 @@
 import static org.hamcrest.Matchers.nullValue;
 
 public class RequestConvertersTests extends ESTestCase {
+
+    private static final DeprecationLogger deprecationLogger = new DeprecationLogger(
+        LogManager.getLogger(RequestConvertersTests.class));
+
     public void testPing() {
         Request request = RequestConverters.ping();
         assertEquals("/", request.getEndpoint());
@@ -1256,7 +1262,7 @@ public void testMultiSearch() throws IOException {
         };
         MultiSearchRequest.readMultiLineFormat(new BytesArray(EntityUtils.toByteArray(request.getEntity())),
                 REQUEST_BODY_CONTENT_TYPE.xContent(), consumer, null, multiSearchRequest.indicesOptions(), null, null, null, null,
-                xContentRegistry(), true);
+                xContentRegistry(), true, deprecationLogger);
         assertEquals(requests, multiSearchRequest.requests());
     }
 

server/src/main/java/org/elasticsearch/action/search/MultiSearchRequest.java

@@ -27,6 +27,7 @@
 import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.logging.DeprecationLogger;
 import org.elasticsearch.common.xcontent.LoggingDeprecationHandler;
 import org.elasticsearch.common.xcontent.NamedXContentRegistry;
 import org.elasticsearch.common.xcontent.ToXContent;
@@ -175,7 +176,8 @@ public static void readMultiLineFormat(BytesReference data,
                                            String searchType,
                                            Boolean ccsMinimizeRoundtrips,
                                            NamedXContentRegistry registry,
-                                           boolean allowExplicitIndex) throws IOException {
+                                           boolean allowExplicitIndex,
+                                           DeprecationLogger deprecationLogger) throws IOException {
         int from = 0;
         byte marker = xContent.streamSeparator();
         while (true) {
@@ -186,6 +188,8 @@ public static void readMultiLineFormat(BytesReference data,
             // support first line with \n
             if (nextMarker == 0) {
                 from = nextMarker + 1;
+                deprecationLogger.deprecated("support for empty first line before any action metadata in msearch API is deprecated and " +
+                    "will be removed in the next major version");
                 continue;
             }
 

server/src/main/java/org/elasticsearch/rest/action/search/RestMultiSearchAction.java

@@ -154,7 +154,7 @@ public static void parseMultiLineRequest(RestRequest request, IndicesOptions ind
         final XContent xContent = sourceTuple.v1().xContent();
         final BytesReference data = sourceTuple.v2();
         MultiSearchRequest.readMultiLineFormat(data, xContent, consumer, indices, indicesOptions, types, routing,
-                searchType, ccsMinimizeRoundtrips, request.getXContentRegistry(), allowExplicitIndex);
+                searchType, ccsMinimizeRoundtrips, request.getXContentRegistry(), allowExplicitIndex, deprecationLogger);
     }
 
     @Override

server/src/test/java/org/elasticsearch/action/search/MultiSearchRequestTests.java

@@ -19,12 +19,14 @@
 
 package org.elasticsearch.action.search;
 
+import org.apache.logging.log4j.LogManager;
 import org.elasticsearch.action.support.IndicesOptions;
 import org.elasticsearch.common.CheckedBiConsumer;
 import org.elasticsearch.common.CheckedRunnable;
 import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.bytes.BytesArray;
+import org.elasticsearch.common.logging.DeprecationLogger;
 import org.elasticsearch.common.xcontent.NamedXContentRegistry;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.common.xcontent.XContentType;
@@ -48,10 +50,15 @@
 import static org.elasticsearch.search.RandomSearchRequestGenerator.randomSearchRequest;
 import static org.elasticsearch.test.EqualsHashCodeTestUtils.checkEqualsAndHashCode;
 import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.nullValue;
 
 public class MultiSearchRequestTests extends ESTestCase {
+
+    private static final DeprecationLogger deprecationLogger = new DeprecationLogger(
+        LogManager.getLogger(MultiSearchRequestTests.class));
+
     public void testSimpleAdd() throws Exception {
         MultiSearchRequest request = parseMultiSearchRequest("/org/elasticsearch/action/search/simple-msearch1.json");
         assertThat(request.requests().size(),
@@ -180,6 +187,28 @@ public void testSimpleAdd4() throws Exception {
         assertThat(request.requests().get(2).routing(), equalTo("123"));
     }
 
+    public void testEmptyFirstLine1() throws Exception {
+        MultiSearchRequest request = parseMultiSearchRequest("/org/elasticsearch/action/search/msearch-empty-first-line1.json");
+        assertThat(request.requests().size(), equalTo(4));
+        for (SearchRequest searchRequest : request.requests()) {
+            assertThat(searchRequest.indices().length, equalTo(0));
+            assertThat(searchRequest.source().query(), instanceOf(MatchAllQueryBuilder.class));
+        }
+        assertWarnings("support for empty first line before any action metadata in msearch API is deprecated and will be removed " +
+            "in the next major version");
+    }
+
+    public void testEmptyFirstLine2() throws Exception {
+        MultiSearchRequest request = parseMultiSearchRequest("/org/elasticsearch/action/search/msearch-empty-first-line2.json");
+        assertThat(request.requests().size(), equalTo(4));
+        for (SearchRequest searchRequest : request.requests()) {
+            assertThat(searchRequest.indices().length, equalTo(0));
+            assertThat(searchRequest.source().query(), instanceOf(MatchAllQueryBuilder.class));
+        }
+        assertWarnings("support for empty first line before any action metadata in msearch API is deprecated and will be removed " +
+            "in the next major version");
+    }
+
     public void testResponseErrorToXContent() {
         long tookInMillis = randomIntBetween(1, 1000);
         MultiSearchResponse response = new MultiSearchResponse(
@@ -262,7 +291,7 @@ public void testMultiLineSerialization() throws IOException {
                 parsedRequest.add(r);
             };
             MultiSearchRequest.readMultiLineFormat(new BytesArray(originalBytes), xContentType.xContent(),
-                    consumer, null, null, null, null, null, null, xContentRegistry(), true);
+                    consumer, null, null, null, null, null, null, xContentRegistry(), true, deprecationLogger);
             assertEquals(originalRequest, parsedRequest);
         }
     }

server/src/test/resources/org/elasticsearch/action/search/msearch-empty-first-line1.json

@@ -0,0 +1,9 @@
+
+
+{ "query": {"match_all": {}}}
+{}
+{ "query": {"match_all": {}}}
+
+{ "query": {"match_all": {}}}
+{}
+{ "query": {"match_all": {}}}

server/src/test/resources/org/elasticsearch/action/search/msearch-empty-first-line2.json

@@ -0,0 +1,9 @@
+
+{}
+{ "query": {"match_all": {}}}
+
+{ "query": {"match_all": {}}}
+{}
+{ "query": {"match_all": {}}}
+
+{ "query": {"match_all": {}}}