Min val should be 0, restored deleted comment

Author: seanstory

docs/reference/elasticsearch/mapping-reference/mapping-field-meta.md

@@ -25,6 +25,7 @@ PUT my-index-000001
 
 ::::{note}
 Field metadata enforces at most 5 entries, that keys have a length that is less than or equal to 20, and that values are strings whose length is less than or equal to 500.
+The value limit is configurable, with the index setting: `index.mapping.meta.length_limit`.
 ::::
 
 

server/src/main/java/org/elasticsearch/index/IndexSettings.java

@@ -858,8 +858,8 @@ private static String getIgnoreAboveDefaultValue(final Settings settings) {
 
     public static final Setting<Integer> INDEX_MAPPING_META_LENGTH_LIMIT_SETTING = Setting.intSetting(
         "index.mapping.meta.length_limit",
-        500, // default value
-        20,  // minimum value
+        500,
+        0,
         Property.IndexScope,
         Property.Final
     );

server/src/main/java/org/elasticsearch/index/mapper/TypeParsers.java

@@ -29,6 +29,9 @@
 public class TypeParsers {
     private static final DeprecationLogger deprecationLogger = DeprecationLogger.getLogger(TypeParsers.class);
 
+    /**
+     * Parse the {@code meta} key of the mapping.
+     */
     public static Map<String, String> parseMeta(String name, Object metaObject, MappingParserContext parserContext) {
         if (metaObject instanceof Map == false) {
             throw new MapperParsingException(