ESQL: Locale and timezone argument for date_parse

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/EsqlFunctionRegistry.java

@@ -1065,13 +1065,17 @@ protected static <T extends Function> FunctionDefinition def(Class<T> function,
                 if (children.size() > 4 || children.size() < 2) {
                     throw new QlIllegalArgumentException("expects minimum two, maximum four arguments");
                 }
+            } else if (ThreeOptionalArguments.class.isAssignableFrom(function)) {
+                if (children.size() > 4 || children.isEmpty()) {
+                    throw new QlIllegalArgumentException("expects minimum one, maximum four arguments");
+                }
             } else if (children.size() != 4) {
                 throw new QlIllegalArgumentException("expects exactly four arguments");
             }
             return ctorRef.build(
                 source,
                 children.get(0),
-                children.get(1),
+                children.size() > 1 ? children.get(1) : null,
                 children.size() > 2 ? children.get(2) : null,
                 children.size() > 3 ? children.get(3) : null
             );

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/ThreeOptionalArguments.java

@@ -0,0 +1,16 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+package org.elasticsearch.xpack.esql.expression.function;
+
+/**
+ * Marker interface indicating that a function accepts three optional arguments (the last three).
+ * This is used by the {@link EsqlFunctionRegistry} to perform validation of function declaration.
+ */
+public interface ThreeOptionalArguments {
+
+}

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateParse.java

@@ -22,13 +22,16 @@
 import org.elasticsearch.xpack.esql.core.type.DataType;
 import org.elasticsearch.xpack.esql.expression.function.Example;
 import org.elasticsearch.xpack.esql.expression.function.FunctionInfo;
-import org.elasticsearch.xpack.esql.expression.function.OptionalArgument;
 import org.elasticsearch.xpack.esql.expression.function.Param;
+import org.elasticsearch.xpack.esql.expression.function.ThreeOptionalArguments;
 import org.elasticsearch.xpack.esql.expression.function.scalar.EsqlScalarFunction;
 import org.elasticsearch.xpack.esql.io.stream.PlanStreamInput;
 
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Locale;
+import java.util.TimeZone;
 
 import static org.elasticsearch.common.time.DateFormatter.forPattern;
 import static org.elasticsearch.xpack.esql.core.expression.TypeResolutions.ParamOrdinal.FIRST;
@@ -38,7 +41,7 @@
 import static org.elasticsearch.xpack.esql.type.EsqlDataTypeConverter.DEFAULT_DATE_TIME_FORMATTER;
 import static org.elasticsearch.xpack.esql.type.EsqlDataTypeConverter.dateTimeToLong;
 
-public class DateParse extends EsqlScalarFunction implements OptionalArgument {
+public class DateParse extends EsqlScalarFunction implements ThreeOptionalArguments {
     public static final NamedWriteableRegistry.Entry ENTRY = new NamedWriteableRegistry.Entry(
         Expression.class,
         "DateParse",
@@ -47,6 +50,8 @@ public class DateParse extends EsqlScalarFunction implements OptionalArgument {
 
     private final Expression field;
     private final Expression format;
+    private final Expression locale;
+    private final Expression timezone;
 
     @FunctionInfo(
         returnType = "date",
@@ -63,17 +68,38 @@ public DateParse(
             name = "dateString",
             type = { "keyword", "text" },
             description = "Date expression as a string. If `null` or an empty string, the function returns `null`."
-        ) Expression second
+        ) Expression second,
+        @Param(name = "dateLocale", type = { "keyword", "text" }, description = "The locale to parse with") Expression third,
+        @Param(name = "dateTimezone", type = { "keyword", "text" }, description = "The timezone to parse with") Expression forth
     ) {
-        super(source, second != null ? List.of(first, second) : List.of(first));
+        super(source, fields(first, second, third, forth));
         this.field = second != null ? second : first;
         this.format = second != null ? first : null;
+        this.locale = third;
+        this.timezone = forth;
+    }
+
+    private static List<Expression> fields(Expression field, Expression format, Expression locale, Expression timezone) {
+        List<Expression> list = new ArrayList<>(3);
+        list.add(field);
+        if (format != null) {
+            list.add(format);
+        }
+        if (locale != null) {
+            list.add(locale);
+        }
+        if (timezone != null) {
+            list.add(timezone);
+        }
+        return list;
     }
 
     private DateParse(StreamInput in) throws IOException {
         this(
             Source.readFrom((PlanStreamInput) in),
             in.readNamedWriteable(Expression.class),
+            in.readOptionalNamedWriteable(Expression.class),
+            in.readOptionalNamedWriteable(Expression.class),
             in.readOptionalNamedWriteable(Expression.class)
         );
     }
@@ -82,7 +108,9 @@ private DateParse(StreamInput in) throws IOException {
     public void writeTo(StreamOutput out) throws IOException {
         source().writeTo(out);
         out.writeNamedWriteable(children().get(0));
-        out.writeOptionalNamedWriteable(children().size() == 2 ? children().get(1) : null);
+        out.writeOptionalNamedWriteable(children().size() > 1 ? children().get(1) : null);
+        out.writeOptionalNamedWriteable(children().size() > 2 ? children().get(2) : null);
+        out.writeOptionalNamedWriteable(children().size() > 3 ? children().get(3) : null);
     }
 
     @Override
@@ -141,9 +169,23 @@ public ExpressionEvaluator.Factory toEvaluator(ToEvaluator toEvaluator) {
         if (DataType.isString(format.dataType()) == false) {
             throw new IllegalArgumentException("unsupported data type for date_parse [" + format.dataType() + "]");
         }
+        String localeAsString = locale == null ? null : ((BytesRef) locale.fold(toEvaluator.foldCtx())).utf8ToString();
+        Locale locale = localeAsString == null ? null : Locale.forLanguageTag(localeAsString);
+        if (localeAsString != null && locale == null) {
+            throw new IllegalArgumentException("unsupported locale [" + localeAsString + "]");
+        }
+
+        String timezoneAsString = timezone == null ? null : ((BytesRef) timezone.fold(toEvaluator.foldCtx())).utf8ToString();
+        TimeZone timezone = timezoneAsString == null ? null : TimeZone.getTimeZone(timezoneAsString);
         if (format.foldable()) {
             try {
                 DateFormatter formatter = toFormatter(format.fold(toEvaluator.foldCtx()));
+                if (locale != null) {
+                    formatter = formatter.withLocale(locale);
+                }
+                if (timezone != null) {
+                    formatter = formatter.withZone(timezone.toZoneId());
+                }
                 return new DateParseConstantEvaluator.Factory(source(), fieldEvaluator, formatter);
             } catch (IllegalArgumentException e) {
                 throw new InvalidArgumentException(e, "invalid date pattern for [{}]: {}", sourceText(), e.getMessage());
@@ -159,13 +201,19 @@ private static DateFormatter toFormatter(Object format) {
 
     @Override
     public Expression replaceChildren(List<Expression> newChildren) {
-        return new DateParse(source(), newChildren.get(0), newChildren.size() > 1 ? newChildren.get(1) : null);
+        return new DateParse(
+            source(),
+            newChildren.get(0),
+            newChildren.size() > 1 ? newChildren.get(1) : null,
+            newChildren.size() > 2 ? newChildren.get(2) : null,
+            newChildren.size() > 3 ? newChildren.get(3) : null
+        );
     }
 
     @Override
     protected NodeInfo<? extends Expression> info() {
         Expression first = format != null ? format : field;
         Expression second = format != null ? field : null;
-        return NodeInfo.create(this, DateParse::new, first, second);
+        return NodeInfo.create(this, DateParse::new, first, second, locale, timezone);
     }
 }