elastic/elasticsearch · error · IllegalArgumentException

Sort direction cannot be null

Error message

Sort direction cannot be null

What it means

Thrown by SortOrder.fromString when the provided sort direction string is null. The static factory method explicitly rejects null before checking against 'asc' and 'desc'.

Source

Thrown at modules/ingest-common/src/main/java/org/elasticsearch/ingest/common/SortProcessor.java:51

    public enum SortOrder {
        ASCENDING("asc"),
        DESCENDING("desc");

        private final String direction;

        SortOrder(String direction) {
            this.direction = direction;
        }

        @Override
        public String toString() {
            return this.direction;
        }

        public static SortOrder fromString(String value) {
            if (value == null) {
                throw new IllegalArgumentException("Sort direction cannot be null");
            }

            if (value.equals(ASCENDING.toString())) {
                return ASCENDING;
            } else if (value.equals(DESCENDING.toString())) {
                return DESCENDING;
            }
            throw new IllegalArgumentException("Sort direction [" + value + "] not recognized." + " Valid values are: [asc, desc]");
        }
    }

    private final String field;
    private final SortOrder order;
    private final String targetField;

    SortProcessor(String tag, String description, String field, SortOrder order, String targetField) {
        super(tag, description);
        this.field = field;

View on GitHub (pinned to db6a809a66)

Solutions

1. Provide an explicit 'order' value of 'asc' or 'desc' in the sort processor config.
2. Default to 'asc' in your config builder when the user omits the order.
3. Validate the order is non-null before constructing the processor.

Example fix

// before
{
  "sort": { "field": "events", "target_field": "events_sorted" }
}
// after
{
  "sort": { "field": "events", "target_field": "events_sorted", "order": "asc" }
}

// Validate order is non-null before constructing SortProcessor
String order = config.get("order");
if (order == null) {
    order = "asc"; // sensible default
}

boolean isNonNullOrder(String order) {
    return order != null;
}

try {
    SortOrder.fromString(order);
} catch (IllegalArgumentException e) {
    if (e.getMessage().equals("Sort direction cannot be null")) {
        order = "asc"; // default
        SortOrder.fromString(order);
    } else { throw e; }
}

When it happens

Trigger: Constructing or configuring a SortProcessor (sort ingest processor) with an order field that is null, or calling SortOrder.fromString(null) directly.

Common situations: Pipeline configuration where the order parameter was omitted and not defaulted. Programmatic construction passing null. JSON config with a missing 'order' key that deserializes to null.

Related errors

• Sort direction [{}] not recognized. Valid values are: [asc,
• field [{}] is null, cannot sort.
• failure store document has unexpected structure, missing req
• failure store document has unexpected structure, missing req
• unable to set domain information for document

AI-assisted analysis of elastic/elasticsearch@db6a809a66 (2026-08-12). Data as JSON: /api/errors/9036b9c1485b6c13. Report an issue: GitHub.