apache/seatunnel · error · IllegalArgumentException

input.on-error must be "skip" or "fail".

Error message

input.on-error must be "skip" or "fail".

What it means

The input.on-error option controls whether the reader skips errored files/records or fails the input. FileCollectConfig.validateOnError accepts only "skip" or "fail" (case-insensitive); any other string throws this IllegalArgumentException.

Source

Thrown at seatunnel-edge-agent/seatunnel-edge-agent-connector/src/main/java/org/apache/seatunnel/edge/agent/connector/config/FileCollectConfig.java:135

    public static FileCollectConfig from(ReadonlyConfig config) {
        return new FileCollectConfig(config);
    }

    public boolean isMultilineEnabled() {
        return multilinePattern != null && !multilinePattern.isEmpty();
    }

    public boolean isJsonOutput() {
        return "json".equalsIgnoreCase(outputType);
    }

    public boolean isSkipOnError() {
        return !"fail".equalsIgnoreCase(onError);
    }

    private static void validateOnError(String value) {
        if (!value.equalsIgnoreCase("skip") && !value.equalsIgnoreCase("fail")) {
            throw new IllegalArgumentException("input.on-error must be \"skip\" or \"fail\".");
        }
    }

    private static void validateMultilineMatch(String value) {
        if (!value.equalsIgnoreCase("after") && !value.equalsIgnoreCase("before")) {
            throw new IllegalArgumentException(
                    "input.multiline.match must be \"after\" or \"before\".");
        }
    }

    private static void validateOutputType(String value) {
        if (!value.equalsIgnoreCase("line") && !value.equalsIgnoreCase("json")) {
            throw new IllegalArgumentException(
                    "input.output-format.type must be \"line\" or \"json\".");
        }
    }

    private static Charset resolveCharset(String encodingName, String inputId) {

View on GitHub (pinned to cf67b549a7)

Solutions

1. Change input.on-error to "skip" (continue on per-file errors)
2. Change input.on-error to "fail" (abort on errors)
3. Check spelling and casing — matching is case-insensitive so only the word itself matters

Example fix

# before
input.on-error = "ignore"
# after
input.on-error = "skip"

String onError = cfg.get(FileCollectOptions.ON_ERROR);
if (!"skip".equalsIgnoreCase(onError) && !"fail".equalsIgnoreCase(onError)) { throw new IllegalArgumentException("on-error must be skip or fail"); }

try { FileCollectConfig.from(config); } catch (IllegalArgumentException e) { log.error("on-error invalid: {}", e.getMessage()); }

When it happens

Trigger: Setting input.on-error to values like "ignore", "continue", "warn", "abort", or a misspelled variant.

Common situations: Users porting configs from other tools (e.g. Logstash/Fluentd vocabulary) whose error-handling keywords differ.

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

• Unknown format type:
• Unknown ftp connection mode: ${mode}
• input.multiline.match must be "after" or "before".
• input.output-format.type must be "line" or "json".
• Unsupported agent.delivery-guarantee: ${value}. Supported: B

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/83653662ebc89751. Report an issue: GitHub.