More Like This: removal of the MLT API

Removes the More Like This API, users should now use the More Like This query.
The MLT API tests were converted to their query equivalent. Also some clean
ups in MLT tests.

Closes #10736
Closes #11003

docs/reference/migration/index.asciidoc

@@ -19,7 +19,8 @@ See <<setup-upgrade>> for more info.
 
 include::migrate_2_0.asciidoc[]
 
+include::migrate_1_6.asciidoc[]
+
 include::migrate_1_4.asciidoc[]
 
 include::migrate_1_0.asciidoc[]
-

docs/reference/migration/migrate_1_6.asciidoc

@@ -0,0 +1,10 @@
+[[breaking-changes-1.6]]
+== Breaking changes in 1.6
+
+This section discusses the changes that you need to be aware of when migrating
+your application from Elasticsearch 1.x to Elasticsearch 1.6.
+
+[float]
+=== More Like This API
+
+The More Like This API query has been deprecated and will be removed in 2.0. Instead use the <<query-dsl-mlt-query, More Like This Query>>.

docs/reference/migration/migrate_2_0.asciidoc

@@ -24,10 +24,10 @@ The following deprecated methods have been removed:
 
 Partial fields were deprecated since 1.0.0beta1 in favor of <<search-request-source-filtering,source filtering>>.
 
-=== More Like This Field
+=== More Like This
 
-The More Like This Field query has been removed in favor of the <<query-dsl-mlt-query, More Like This Query>>
-restrained set to a specific `field`.
+The More Like This API and the More Like This Field query have been removed in
+favor of the <<query-dsl-mlt-query, More Like This Query>>.
 
 === Routing
 

docs/reference/search.asciidoc

@@ -101,7 +101,4 @@ include::search/explain.asciidoc[]
 
 include::search/percolate.asciidoc[]
 
-include::search/more-like-this.asciidoc[]
-
 include::search/field-stats.asciidoc[]
-

rest-api-spec/test/mlt/10_basic.yaml

@@ -30,11 +30,16 @@
            wait_for_status: green
 
   - do:
-      mlt:
-          index:  test_1
-          type:   test
-          id:     1
-          mlt_fields: title
-
+      search:
+          index:   test_1
+          type:    test
+          body:
+            query:
+              more_like_this:
+                like:
+                  -
+                    _id: 1
+                fields: ["title"]
+
   - match: {hits.total: 0}
 

src/main/java/org/elasticsearch/action/ActionModule.java

@@ -139,8 +139,6 @@
 import org.elasticsearch.action.indexedscripts.get.TransportGetIndexedScriptAction;
 import org.elasticsearch.action.indexedscripts.put.PutIndexedScriptAction;
 import org.elasticsearch.action.indexedscripts.put.TransportPutIndexedScriptAction;
-import org.elasticsearch.action.mlt.MoreLikeThisAction;
-import org.elasticsearch.action.mlt.TransportMoreLikeThisAction;
 import org.elasticsearch.action.percolate.*;
 import org.elasticsearch.action.search.*;
 import org.elasticsearch.action.search.type.*;
@@ -293,7 +291,6 @@ protected void configure() {
                 TransportSearchScrollQueryAndFetchAction.class
         );
         registerAction(MultiSearchAction.INSTANCE, TransportMultiSearchAction.class);
-        registerAction(MoreLikeThisAction.INSTANCE, TransportMoreLikeThisAction.class);
         registerAction(PercolateAction.INSTANCE, TransportPercolateAction.class);
         registerAction(MultiPercolateAction.INSTANCE, TransportMultiPercolateAction.class, TransportShardMultiPercolateAction.class);
         registerAction(ExplainAction.INSTANCE, TransportExplainAction.class);