apache/seatunnel · error · SeaTunnelRuntimeException

COMMON-02

COMMON-02

Error message

<identifier> JSON convert/parse '<payload>' operation failed.

What it means

ClickHouse sink's StringInjectFunction.injectFields() writes a Java field value into a JDBC PreparedStatement. For nested ClickHouse types (e.g. multidimensional arrays of Doubles) it parses the value's string form with Jackson (MAPPER.readValue). If the string is not valid/expected JSON, JsonProcessingException is caught and rethrown as CommonError.jsonOperationError("Clickhouse", value, e) (COMMON-02).

Source

Thrown at seatunnel-connectors-v2/connector-clickhouse/src/main/java/org/apache/seatunnel/connectors/seatunnel/clickhouse/sink/inject/StringInjectFunction.java:53

            throws SQLException {
        try {
            if ("Point".equals(fieldType)) {
                statement.setObject(
                        index, MAPPER.readValue(replace(value.toString()), double[].class));
            } else if ("Ring".equals(fieldType)) {
                statement.setObject(
                        index, MAPPER.readValue(replace(value.toString()), double[][].class));
            } else if ("Polygon".equals(fieldType)) {
                statement.setObject(
                        index, MAPPER.readValue(replace(value.toString()), double[][][].class));
            } else if ("MultiPolygon".equals(fieldType)) {
                statement.setObject(
                        index, MAPPER.readValue(replace(value.toString()), double[][][][].class));
            } else {
                statement.setString(index, value.toString());
            }
        } catch (JsonProcessingException e) {
            throw CommonError.jsonOperationError("Clickhouse", value.toString(), e);
        }
    }

    @Override
    public boolean isCurrentFieldType(String fieldType) {
        if ("String".equals(fieldType)
                || "Int128".equals(fieldType)
                || "UInt128".equals(fieldType)
                || "Int256".equals(fieldType)
                || "UInt256".equals(fieldType)
                || "Point".equals(fieldType)
                || "Ring".equals(fieldType)
                || "Polygon".equals(fieldType)
                || "MultiPolygon".equals(fieldType)) {
            this.fieldType = fieldType;
            return true;
        }
        return false;

View on GitHub (pinned to cf67b549a7)

Solutions

1. Inspect the '<payload>' in the error message and fix the upstream data to be valid JSON matching the target ClickHouse type (e.g. [[1.0,2.0]] for double[][]).
2. Add a transform upstream to sanitize/normalize nested array values into strict JSON before the sink.
3. Change the ClickHouse column type (or schema mapping) so the value uses setString instead of JSON parsing if it's plain text.
4. Check the wrapped JsonProcessingException cause to identify the exact malformed position.

Example fix

// before (value)
"[[1.0, 2.0], [3.0]]'  // trailing quote, invalid JSON
// after
"[[1.0,2.0],[3.0]]"

java
// Pre-validate nested array values are strict JSON before the ClickHouse sink
String s = value.toString();
new ObjectMapper().readTree(s); // throws if not valid JSON — validate upstream

java
try {
    injectFunction.injectFields(statement, index, value, fieldType);
} catch (SeaTunnelException e) {
    if (e.getMessage().contains("JSON convert/parse")) {
        // log payload; sanitize or dead-letter the record
    } else { throw e; }
}

When it happens

Trigger: Injecting a String field into a ClickHouse column backed by StringInjectFunction where the value must be parsed as JSON (e.g. double[][][][]) but the value's toString() is not parseable JSON — malformed arrays, single quotes, unquoted strings, or non-array scalars.

Common situations: Upstream data contains non-JSON strings (e.g. '[1,2,' truncated, or "1.0" where a nested array is expected); values serialized with single quotes or Python-style repr; encoding/escaping issues from a source connector.

Understand the failure class

Background: JSON parse error: "Unexpected token" / "not valid JSON" / "failed to parse" — what JSON parsers are really complaining about — this error's family across 45 libraries.

Related errors

• COMMON_SQL_OPERATION_FAILED
• COMMON_FLUSH_DATA_FAILED
• array inject error, unsupported data type: " + type
• Failed to execute query: %s
• Failed to convert row to JSON

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/5a7e77628a5f6e67. Report an issue: GitHub.