apache/seatunnel · error · IllegalArgumentException

Value is not a BSON date or timestamp

Error message

Value is not a BSON date or timestamp

What it means

DocumentDBItemDeserializer.convertDateTime expects a BSON value of type DateTime or Timestamp to produce a LocalDateTime. If the BSON value is any other type (string, int32, null, etc.) it throws this IllegalArgumentException, because SeaTunnel's timestamp column requires an actual BSON date/timestamp value.

Source

Thrown at seatunnel-connectors-v2/connector-amazondocumentdb/src/main/java/org/apache/seatunnel/connectors/seatunnel/amazondocumentdb/serialize/DocumentDBItemDeserializer.java:197

            return value.asString().getValue();
        }
        if (value.isObjectId()) {
            return value.asObjectId().getValue().toHexString();
        }
        if (value.isDocument()) {
            return value.asDocument().toJson(RELAXED_JSON_SETTINGS);
        }
        return value.toString();
    }

    private static LocalDateTime convertDateTime(BsonValue value) {
        Instant instant;
        if (value.isDateTime()) {
            instant = Instant.ofEpochMilli(value.asDateTime().getValue());
        } else if (value.isTimestamp()) {
            instant = Instant.ofEpochSecond(value.asTimestamp().getTime());
        } else {
            throw new IllegalArgumentException("Value is not a BSON date or timestamp");
        }
        return LocalDateTime.ofInstant(instant, ZoneId.systemDefault());
    }

    /** Converts array elements recursively so nested rows, maps, and arrays use the same rules. */
    private Object convertArray(String field, ArrayType<?, ?> type, BsonValue value) {
        List<BsonValue> source = value.asArray();
        Object target = Array.newInstance(type.getElementType().getTypeClass(), source.size());
        for (int i = 0; i < source.size(); i++) {
            Array.set(target, i, convert(field, type.getElementType(), source.get(i)));
        }
        return target;
    }

    /** Converts BSON documents to maps; BSON field names require a string map key type. */
    private Map<String, Object> convertMap(String field, MapType<?, ?> type, BsonValue value) {
        if (type.getKeyType().getSqlType() != SqlType.STRING) {
            throw conversionError(field, type);

View on GitHub (pinned to cf67b549a7)

Solutions

1. Fix the data in DocumentDB to store the value as a BSON Date ($toDate in an update pipeline).
2. Change the SeaTunnel schema column to STRING if the source stores date strings, then transform/parse downstream.
3. Add a transform (e.g. with a custom deserializer or Transform) that parses string dates into timestamps before this converter runs.

Example fix

// before: document stores {"ts": "2024-01-01T00:00:00Z"} mapped to TIMESTAMP
// after: convert in MongoDB/DocumentDB
 db.coll.updateMany({}, [{ $set: { ts: { $toDate: "$ts" } } }])

if (!(bsonValue.isDateTime() || bsonValue.isTimestamp())) {
    throw new IllegalArgumentException("Field must be BSON Date or Timestamp, got: " + bsonValue.getBsonType());
}

boolean isBsonDateLike(BsonValue v) { return v != null && (v.isDateTime() || v.isTimestamp()); }

try { value = convertDateTime(field, type, bsonValue); } catch (IllegalArgumentException e) { log.warn("Non-date value for {}: {}", field, bsonValue); handleNull(); }

When it happens

Trigger: A document field declared as TIMESTAMP in the SeaTunnel schema contains a BSON string (e.g. "2024-01-01T00:00:00Z") or numeric value instead of a BSON Date (ISODate) or BSON Timestamp.

Common situations: Documents written by different applications with inconsistent typing; data migrated from another store as plain strings; schema mapping declared the field as TIMESTAMP while the collection stores ISO-8601 strings.

Understand the failure class

Background: Type mismatch errors: IllegalArgumentException, TypeError and type guards across 150 open-source libraries — this error's family across 150 libraries.

Related errors

• Sparse vector value must be a Number, but got: %s
• Unsupported datetime format:
• Unsupported timestamp type:
• Decimal precision %d exceeds configured precision %d
• Failed to open AmazonDocumentDB source reader for database [

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/b6f619b704bc8221. Report an issue: GitHub.