[ES|QL] Optional named arguments for function in map - option #1

docs/changelog/117872.yaml

@@ -0,0 +1,5 @@
+pr: 117872
+summary: "Optional named arguments for function in map - option #1"
+area: ES|QL
+type: enhancement
+issues: []

x-pack/plugin/esql/compute/gen/src/main/java/org/elasticsearch/compute/gen/ConsumeProcessor.java

@@ -39,6 +39,7 @@ public Set<String> getSupportedAnnotationTypes() {
             "org.elasticsearch.injection.guice.Inject",
             "org.elasticsearch.xpack.esql.expression.function.FunctionInfo",
             "org.elasticsearch.xpack.esql.expression.function.Param",
+            "org.elasticsearch.xpack.esql.expression.function.MapParam",
             "org.elasticsearch.rest.ServerlessScope",
             "org.elasticsearch.xcontent.ParserConstructor",
             "org.elasticsearch.core.UpdateForV9",

x-pack/plugin/esql/qa/testFixtures/src/main/resources/map-functions.csv-spec

@@ -0,0 +1,71 @@
+// Tests to validate maps as inputs to functions, these functions are under snapshot only
+
+mapCount
+required_capability: optional_named_argument_map_for_function
+ROW x = 1
+| EVAL c = map_count({"option1":"value1", "option2":2, "option3":3.0, "option4":true})
+;
+
+x:integer |c:long
+1         |4
+;
+
+mapCountIndex
+required_capability: optional_named_argument_map_for_function
+FROM employees
+| EVAL c = map_count({"option1":"value1", "option2":2, "option3":3.0, "option4":true})
+| KEEP emp_no, c
+| SORT emp_no
+| LIMIT 1
+;
+
+emp_no:integer |c:long
+10001          |4
+;
+
+
+mapKeys
+required_capability: optional_named_argument_map_for_function
+ROW x = 1
+| EVAL k = map_keys({"option1":"value1", "option2":2, "option3":3.0, "option4":true})
+;
+
+x:integer |k:keyword
+1         |"option1, option2, option3, option4"
+;
+
+mapKeysIndex
+required_capability: optional_named_argument_map_for_function
+FROM employees
+| EVAL k = map_keys({"option1":"value1", "option2":2, "option3":3.0, "option4":true})
+| KEEP emp_no, k
+| SORT emp_no
+| LIMIT 1
+;
+
+emp_no:integer |k:keyword
+10001          |"option1, option2, option3, option4"
+;
+
+mapValues
+required_capability: optional_named_argument_map_for_function
+ROW x = 1
+| EVAL v = map_values({"option1":"value1", "option2":2, "option3":3.0, "option4":true})
+;
+
+x:integer |v:keyword
+1         |"value1, 2, 3.0, true"
+;
+
+mapKeysIndex
+required_capability: optional_named_argument_map_for_function
+FROM employees
+| EVAL v = map_values({"option1":"value1", "option2":2, "option3":3.0, "option4":true})
+| KEEP emp_no, v
+| SORT emp_no
+| LIMIT 1
+;
+
+emp_no:integer |v:keyword
+10001          |"value1, 2, 3.0, true"
+;

x-pack/plugin/esql/src/main/antlr/EsqlBaseLexer.g4

@@ -216,6 +216,9 @@ ASTERISK : '*';
 SLASH : '/';
 PERCENT : '%';
 
+LEFT_BRACES : {this.isDevVersion()}? '{';
+RIGHT_BRACES : {this.isDevVersion()}? '}';
+
 NESTED_WHERE : WHERE -> type(WHERE);
 
 NAMED_OR_POSITIONAL_PARAM

x-pack/plugin/esql/src/main/antlr/EsqlBaseParser.g4

@@ -102,13 +102,26 @@ primaryExpression
     ;
 
 functionExpression
-    : functionName LP (ASTERISK | (booleanExpression (COMMA booleanExpression)*))? RP
+    : functionName LP (ASTERISK | (functionArgument (COMMA functionArgument)*))? RP
     ;
 
 functionName
     : identifierOrParameter
     ;
 
+functionArgument
+    : booleanExpression                                                                 #functionArgumentDefault
+    | {this.isDevVersion()}? LEFT_BRACES namedConstants RIGHT_BRACES                    #functionArgumentWithName
+    ;
+
+namedConstants
+    : namedConstant (COMMA namedConstant)*
+    ;
+
+namedConstant
+    : key=string COLON value=constant
+    ;
+
 dataType
     : identifier                                                                        #toDataType
     ;

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/action/EsqlCapabilities.java

@@ -550,7 +550,12 @@ public enum Cap {
         /**
          * Support the "METADATA _score" directive to enable _score column.
          */
-        METADATA_SCORE(Build.current().isSnapshot());
+        METADATA_SCORE(Build.current().isSnapshot()),
+
+        /**
+         * Support named argument for function in map format.
+         */
+        OPTIONAL_NAMED_ARGUMENT_MAP_FOR_FUNCTION(Build.current().isSnapshot());
 
         private final boolean enabled;