apache/dolphinscheduler · error · TaskException

shell task params is not valid

Error message

shell task params is not valid

What it means

ShellTask.init() parses the task's JSON params into ShellParameters via JSONUtils and validates them. If parsing yields null or ShellParameters.checkParameters() returns false, a TaskException is thrown with this message. checkParameters() fails when the shell script body is empty/absent, so the task has nothing to execute.

Source

Thrown at dolphinscheduler-task-plugin/dolphinscheduler-task-shell/src/main/java/org/apache/dolphinscheduler/plugin/task/shell/ShellTask.java:56

    private ShellParameters shellParameters;

    private final ShellCommandExecutor shellCommandExecutor;

    public ShellTask(TaskExecutionContext taskExecutionContext) {
        super(taskExecutionContext);

        this.shellCommandExecutor = new ShellCommandExecutor(taskExecutionContext);
    }

    @Override
    public void init() {

        shellParameters = JSONUtils.parseObject(taskRequest.getTaskParams(), ShellParameters.class);
        log.info("Initialize shell task params {}", JSONUtils.toPrettyJsonString(shellParameters));

        if (shellParameters == null || !shellParameters.checkParameters()) {
            throw new TaskException("shell task params is not valid");
        }
    }

    @SuppressWarnings("unchecked")
    @Override
    public void handle(TaskCallBack taskCallBack) throws TaskException {
        try {
            IShellInterceptorBuilder<?, ?> shellActuatorBuilder = ShellInterceptorBuilderFactory.newBuilder()
                    .properties(ParameterUtils.convert(taskRequest.getPrepareParamsMap()))
                    .appendScript(shellParameters.getRawScript());

            TaskResponse commandExecuteResult = shellCommandExecutor.run(shellActuatorBuilder, taskCallBack);
            setExitStatusCode(commandExecuteResult.getExitStatusCode());
            setProcessId(commandExecuteResult.getProcessId());
            shellParameters.dealOutParam(shellCommandExecutor.getTaskOutputParams());
            taskRequest.setVarPool(shellParameters.getVarPool());
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();

View on GitHub (pinned to 02eac45a1b)

Solutions

1. Open the task definition and enter the shell script in the Script field (rawScript must be non-empty)
2. Validate the task params JSON before submitting: JSONUtils.parseObject(params, ShellParameters.class) != null and checkParameters() == true
3. If submitting via API/Python SDK, confirm the taskParams object includes the script content and that it is serialized once, not double-encoded

Example fix

// before (API request with empty script)
{"taskType":"SHELL","taskParams":{"localParams":[]}}
// after
{"taskType":"SHELL","taskParams":{"rawScript":"echo hello","localParams":[]}}

ShellParameters p = JSONUtils.parseObject(taskRequest.getTaskParams(), ShellParameters.class);
if (p == null || !p.checkParameters()) {
    throw new IllegalArgumentException("shell task params missing or script empty");
}

boolean isValidShellParams(String json) {
    ShellParameters p = JSONUtils.parseObject(json, ShellParameters.class);
    return p != null && p.checkParameters();
}

When it happens

Trigger: TaskExecutionContext.getTaskParams() is null/blank, is not valid JSON, or deserializes to a ShellParameters whose localParams/rawScript field is empty so checkParameters() returns false.

Common situations: Workflow saved with an empty script editor box; upstream automation posted a task-def JSON missing the script field; params corrupted by double-encoding the JSON when calling the API.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

• dvc task params is not valid
• EMR Serverless task params are not valid
• emr task params is not valid
• flink task params is not valid
• flink task params is not valid

AI-assisted analysis of apache/dolphinscheduler@02eac45a1b (2026-09-06). Data as JSON: /api/errors/445df6490600a167. Report an issue: GitHub.