Allow doc-values only search on ip fields (#82929)

Allows searching on ip fields when those fields are not indexed (index: false) but just doc values are enabled.

This enables searches on archive data, which has access to doc values but not index structures. When combined with
searchable snapshots, it allows downloading only data for a given (doc value) field to quickly filter down to a select set
of documents.

Relates #81210 and #52728

Author: ywelsch

docs/reference/mapping/params/doc-values.asciidoc

@@ -17,8 +17,8 @@ makes this data access pattern possible. They store the same values as the
 sorting and aggregations. Doc values are supported on almost all field types,
 with the __notable exception of `text` and `annotated_text` fields__.
 
-<<number,Numeric types>>, <<date,date types>>, the <<boolean,boolean type>>
-and the <<keyword,keyword type>>
+<<number,Numeric types>>, <<date,date types>>, the <<boolean,boolean type>>,
+the <<ip,ip type>> and the <<keyword,keyword type>>
 can also be queried using term or range-based queries
 when they are not <<mapping-index,indexed>> but only have doc values enabled.
 Query performance on doc values is much slower than on index structures, but

docs/reference/mapping/types/ip.asciidoc

@@ -57,7 +57,10 @@ The following parameters are accepted by `ip` fields:
 
 <<mapping-index,`index`>>::
 
-    Should the field be searchable? Accepts `true` (default) and `false`.
+    Should the field be quickly searchable? Accepts `true` (default) and
+    `false`. Fields that only have <<doc-values,`doc_values`>>
+    enabled can still be queried using term or range-based queries,
+    albeit slower.
 
 <<null-value,`null_value`>>::
 

docs/reference/query-dsl.asciidoc

@@ -33,8 +33,8 @@ the stability of the cluster. Those queries can be categorised as follows:
 
 * Queries that need to do linear scans to identify matches:
 ** <<query-dsl-script-query,`script` queries>>
-** queries on <<number,numeric>>, <<date,date>>, <<boolean,boolean>>, or <<keyword,keyword>> fields that are not indexed
-   but have <<doc-values,doc values>> enabled
+** queries on <<number,numeric>>, <<date,date>>, <<boolean,boolean>>, <<ip,ip>> or <<keyword,keyword>> fields
+   that are not indexed but have <<doc-values,doc values>> enabled
 
 * Queries that have a high up-front cost:
 ** <<query-dsl-fuzzy-query,`fuzzy` queries>> (except on

rest-api-spec/src/yamlRestTest/resources/rest-api-spec/test/field_caps/10_basic.yml

@@ -92,6 +92,9 @@ setup:
                   non_indexed_boolean:
                     type:     boolean
                     index:    false
+                  non_indexed_ip:
+                    type:     ip
+                    index:    false
                   geo:
                     type:     keyword
                   object:
@@ -255,6 +258,18 @@ setup:
 
   - match: {fields.non_indexed_boolean.boolean.searchable:                 true}
 
+---
+"Field caps for ip field with only doc values":
+  - skip:
+      version: " - 8.0.99"
+      reason: "doc values search was added in 8.1.0"
+  - do:
+      field_caps:
+        index: 'test1,test2,test3'
+        fields: non_indexed_ip
+
+  - match: {fields.non_indexed_ip.ip.searchable:                          true}
+
 ---
 "Get object and nested field caps":
 

rest-api-spec/src/yamlRestTest/resources/rest-api-spec/test/search/390_doc_values_search.yml

@@ -42,6 +42,9 @@ setup:
               boolean:
                 type: boolean
                 index: false
+              ip:
+                type: ip
+                index: false
 
   - do:
       index:
@@ -58,6 +61,7 @@ setup:
           date: "2017/01/01"
           keyword: "key1"
           boolean: "false"
+          ip: "192.168.0.1"
 
   - do:
       index:
@@ -74,6 +78,7 @@ setup:
           date: "2017/01/02"
           keyword: "key2"
           boolean: "true"
+          ip: "192.168.0.2"
 
   - do:
       indices.refresh: {}
@@ -284,3 +289,30 @@ setup:
         index: test
         body: { query: { range: { boolean: { gte: "false" } } } }
   - length:   { hits.hits: 2  }
+
+---
+"Test match query on ip field where only doc values are enabled":
+
+  - do:
+      search:
+        index: test
+        body: { query: { match: { ip: { query: "192.168.0.1" } } } }
+  - length:   { hits.hits: 1  }
+
+---
+"Test terms query on ip field where only doc values are enabled":
+
+  - do:
+      search:
+        index: test
+        body: { query: { terms: { ip: [ "192.168.0.1", "192.168.0.2" ] } } }
+  - length:   { hits.hits: 2  }
+
+---
+"Test range query on ip field where only doc values are enabled":
+
+  - do:
+      search:
+        index: test
+        body: { query: { range: { ip: { gte: "192.168.0.1" } } } }
+  - length:   { hits.hits: 2  }

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

@@ -14,6 +14,7 @@
 import org.apache.lucene.document.StoredField;
 import org.apache.lucene.index.LeafReaderContext;
 import org.apache.lucene.search.MatchNoDocsQuery;
+import org.apache.lucene.search.PointRangeQuery;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.util.BytesRef;
 import org.elasticsearch.Version;
@@ -204,14 +205,27 @@ public IpFieldType(
         }
 
         public IpFieldType(String name) {
-            this(name, true, false, true, null, null, Collections.emptyMap(), false);
+            this(name, true, true);
+        }
+
+        public IpFieldType(String name, boolean isIndexed) {
+            this(name, isIndexed, true);
+        }
+
+        public IpFieldType(String name, boolean isIndexed, boolean hasDocValues) {
+            this(name, isIndexed, false, hasDocValues, null, null, Collections.emptyMap(), false);
         }
 
         @Override
         public String typeName() {
             return CONTENT_TYPE;
         }
 
+        @Override
+        public boolean isSearchable() {
+            return isIndexed() || hasDocValues();
+        }
+
         @Override
         public boolean mayExistInIndex(SearchExecutionContext context) {
             return context.fieldExistsInIndex(name());
@@ -252,25 +266,48 @@ protected Object parseSourceValue(Object value) {
 
         @Override
         public Query termQuery(Object value, @Nullable SearchExecutionContext context) {
-            failIfNotIndexed();
+            failIfNotIndexedNorDocValuesFallback(context);
+            Query query;
             if (value instanceof InetAddress) {
-                return InetAddressPoint.newExactQuery(name(), (InetAddress) value);
+                query = InetAddressPoint.newExactQuery(name(), (InetAddress) value);
             } else {
                 if (value instanceof BytesRef) {
                     value = ((BytesRef) value).utf8ToString();
                 }
                 String term = value.toString();
                 if (term.contains("/")) {
                     final Tuple<InetAddress, Integer> cidr = InetAddresses.parseCidr(term);
-                    return InetAddressPoint.newPrefixQuery(name(), cidr.v1(), cidr.v2());
+                    query = InetAddressPoint.newPrefixQuery(name(), cidr.v1(), cidr.v2());
+                } else {
+                    InetAddress address = InetAddresses.forString(term);
+                    query = InetAddressPoint.newExactQuery(name(), address);
                 }
-                InetAddress address = InetAddresses.forString(term);
-                return InetAddressPoint.newExactQuery(name(), address);
+            }
+            if (isIndexed()) {
+                return query;
+            } else {
+                return convertToDocValuesQuery(query);
             }
         }
 
+        static Query convertToDocValuesQuery(Query query) {
+            assert query instanceof PointRangeQuery;
+            PointRangeQuery pointRangeQuery = (PointRangeQuery) query;
+            return SortedSetDocValuesField.newSlowRangeQuery(
+                pointRangeQuery.getField(),
+                new BytesRef(pointRangeQuery.getLowerPoint()),
+                new BytesRef(pointRangeQuery.getUpperPoint()),
+                true,
+                true
+            );
+        }
+
         @Override
         public Query termsQuery(Collection<?> values, SearchExecutionContext context) {
+            failIfNotIndexedNorDocValuesFallback(context);
+            if (isIndexed() == false) {
+                return super.termsQuery(values, context);
+            }
             InetAddress[] addresses = new InetAddress[values.size()];
             int i = 0;
             for (Object value : values) {
@@ -301,14 +338,15 @@ public Query rangeQuery(
             boolean includeUpper,
             SearchExecutionContext context
         ) {
-            failIfNotIndexed();
-            return rangeQuery(
-                lowerTerm,
-                upperTerm,
-                includeLower,
-                includeUpper,
-                (lower, upper) -> InetAddressPoint.newRangeQuery(name(), lower, upper)
-            );
+            failIfNotIndexedNorDocValuesFallback(context);
+            return rangeQuery(lowerTerm, upperTerm, includeLower, includeUpper, (lower, upper) -> {
+                Query query = InetAddressPoint.newRangeQuery(name(), lower, upper);
+                if (isIndexed()) {
+                    return query;
+                } else {
+                    return convertToDocValuesQuery(query);
+                }
+            });
         }
 
         /**