elastic/elasticsearch · error · IllegalArgumentException

Unsupported token [{token}]

Error message

Unsupported token [{token}]

What it means

Error "Unsupported token [{token}]" thrown in elastic/elasticsearch.

Source

Thrown at modules/aggregations/src/main/java/org/elasticsearch/aggregations/pipeline/BucketSortPipelineAggregationBuilder.java:77

            List<SortBuilder<?>> sorts = SortBuilder.fromXContent(p);
            List<FieldSortBuilder> fieldSorts = new ArrayList<>(sorts.size());
            for (SortBuilder<?> sort : sorts) {
                if (sort instanceof FieldSortBuilder == false) {
                    throw new IllegalArgumentException(
                        "[" + NAME + "] only supports field based sorting; incompatible sort: [" + sort + "]"
                    );
                }
                fieldSorts.add((FieldSortBuilder) sort);
            }
            return fieldSorts;
        }, SearchSourceBuilder.SORT_FIELD, ObjectParser.ValueType.OBJECT_ARRAY);
        PARSER.declareInt(BucketSortPipelineAggregationBuilder::from, FROM);
        PARSER.declareInt(BucketSortPipelineAggregationBuilder::size, SIZE);
        PARSER.declareField(BucketSortPipelineAggregationBuilder::gapPolicy, p -> {
            if (p.currentToken() == XContentParser.Token.VALUE_STRING) {
                return GapPolicy.parse(p.text().toLowerCase(Locale.ROOT), p.getTokenLocation());
            }
            throw new IllegalArgumentException("Unsupported token [" + p.currentToken() + "]");
        }, GAP_POLICY, ObjectParser.ValueType.STRING);
    }

    private List<FieldSortBuilder> sorts = Collections.emptyList();
    private int from = 0;
    private Integer size;
    private GapPolicy gapPolicy = GapPolicy.SKIP;

    public BucketSortPipelineAggregationBuilder(String name, List<FieldSortBuilder> sorts) {
        super(name, NAME, sorts == null ? new String[0] : sorts.stream().map(FieldSortBuilder::getFieldName).toArray(String[]::new));
        this.sorts = sorts == null ? Collections.emptyList() : sorts;
    }

    /**
     * Read from a stream.
     */
    public BucketSortPipelineAggregationBuilder(StreamInput in) throws IOException {
        super(in, NAME);

View on GitHub (pinned to db6a809a66)

When it happens

Trigger: Thrown at modules/aggregations/src/main/java/org/elasticsearch/aggregations/pipeline/BucketSortPipelineAggregationBuilder.java:77 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of elastic/elasticsearch@db6a809a66 (2026-08-12). Data as JSON: /api/errors/0ba2a686e92bd3a6. Report an issue: GitHub.