elastic/elasticsearch · error · ParsingException

Unknown key for a {token} in [{pipelineAggregatorName}]: [{c

Error message

Unknown key for a {token} in [{pipelineAggregatorName}]: [{currentFieldName}].

What it means

Error "Unknown key for a {token} in [{pipelineAggregatorName}]: [{currentFieldName}]." thrown in elastic/elasticsearch.

Source

Thrown at modules/aggregations/src/main/java/org/elasticsearch/aggregations/pipeline/DerivativePipelineAggregationBuilder.java:189

        String[] bucketsPaths = null;
        String format = null;
        String units = null;
        GapPolicy gapPolicy = null;

        while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
            if (token == XContentParser.Token.FIELD_NAME) {
                currentFieldName = parser.currentName();
            } else if (token == XContentParser.Token.VALUE_STRING) {
                if (FORMAT_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
                    format = parser.text();
                } else if (BUCKETS_PATH_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
                    bucketsPaths = new String[] { parser.text() };
                } else if (GAP_POLICY_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
                    gapPolicy = GapPolicy.parse(parser.text(), parser.getTokenLocation());
                } else if (UNIT_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
                    units = parser.text();
                } else {
                    throw new ParsingException(
                        parser.getTokenLocation(),
                        "Unknown key for a " + token + " in [" + pipelineAggregatorName + "]: [" + currentFieldName + "]."
                    );
                }
            } else if (token == XContentParser.Token.START_ARRAY) {
                if (BUCKETS_PATH_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
                    List<String> paths = new ArrayList<>();
                    while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
                        String path = parser.text();
                        paths.add(path);
                    }
                    bucketsPaths = paths.toArray(new String[paths.size()]);
                } else {
                    throw new ParsingException(
                        parser.getTokenLocation(),
                        "Unknown key for a " + token + " in [" + pipelineAggregatorName + "]: [" + currentFieldName + "]."
                    );
                }

View on GitHub (pinned to db6a809a66)

When it happens

Trigger: Thrown at modules/aggregations/src/main/java/org/elasticsearch/aggregations/pipeline/DerivativePipelineAggregationBuilder.java:189 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/1b62857bfb7ebd6c. Report an issue: GitHub.