Add deprecation logging for lenient boolean queries (#21570)

* Add deprecation logging for lenient boolean queries

Relates to #21555, this is the deprecation logging for what was removed.

* Make logger final and correct misspelled word

Author: dakrone

core/src/main/java/org/elasticsearch/index/mapper/BooleanFieldMapper.java

@@ -27,6 +27,8 @@
 import org.apache.lucene.util.BytesRef;
 import org.elasticsearch.common.Booleans;
 import org.elasticsearch.common.Nullable;
+import org.elasticsearch.common.logging.DeprecationLogger;
+import org.elasticsearch.common.logging.Loggers;
 import org.elasticsearch.common.lucene.Lucene;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.XContentBuilder;
@@ -53,6 +55,8 @@ public class BooleanFieldMapper extends FieldMapper {
 
     public static final String CONTENT_TYPE = "boolean";
 
+    private static final DeprecationLogger deprecationLogger = new DeprecationLogger(Loggers.getLogger(BooleanFieldMapper.class));
+
     public static class Defaults {
         public static final MappedFieldType FIELD_TYPE = new BooleanFieldType();
 
@@ -152,16 +156,25 @@ public BytesRef indexedValueForSearch(Object value) {
             } else {
                 sValue = value.toString();
             }
-            if (sValue.length() == 0) {
-                return Values.FALSE;
-            }
-            if (sValue.length() == 1 && sValue.charAt(0) == 'F') {
-                return Values.FALSE;
-            }
-            if (Booleans.parseBoolean(sValue, false)) {
-                return Values.TRUE;
+            switch (sValue) {
+                case "true":
+                    return Values.TRUE;
+                case "false":
+                    return Values.FALSE;
+                default:
+                    deprecationLogger.deprecated("searching using boolean value [" + sValue +
+                                    "] is deprecated, please use [true] or [false]");
+                    if (sValue.length() == 0) {
+                        return Values.FALSE;
+                    }
+                    if (sValue.length() == 1 && sValue.charAt(0) == 'F') {
+                        return Values.FALSE;
+                    }
+                    if (Booleans.parseBoolean(sValue, false)) {
+                        return Values.TRUE;
+                    }
+                    return Values.FALSE;
             }
-            return Values.FALSE;
         }
 
         @Override

docs/reference/mapping/types/boolean.asciidoc

@@ -13,6 +13,10 @@ True values::
 
     Anything that isn't false.
 
+deprecated[5.1.0 While Elasticsearch will currently accept the above values during index time.
+Searching a boolean field using these pseudo-boolean values is deprecated.
+Please use "true" or "false" instead.]
+
 For example:
 
 [source,js]
@@ -32,21 +36,21 @@ PUT my_index
 
 POST my_index/my_type/1
 {
-  "is_published": true <1>
+  "is_published": 1 <1>
 }
 
 GET my_index/_search
 {
   "query": {
     "term": {
-      "is_published": 1 <2>
+      "is_published": true <2>
     }
   }
 }
 --------------------------------------------------
 // CONSOLE
-<1> Indexing a document with a JSON `true`.
-<2> Querying for the document with `1`, which is interpreted as `true`.
+<1> Indexing a document with `1`, which is interpreted as `true`.
+<2> Searching for documents with a JSON `true`.
 
 Aggregations like the <<search-aggregations-bucket-terms-aggregation,`terms`
 aggregation>>  use `1` and `0` for the `key`, and the strings `"true"` and