apache/dolphinscheduler · error · IllegalArgumentException

Http request body should be a json object, but got: %s

Error message

Http request body should be a json object, but got: %s

What it means

A body-parsing guard in getRequestBody: when the condition/body is treated as JSON, parsing produced something that is not a JSON object (array, scalar, or unparseable string), so it cannot be converted to the required Map<String,Object> request body. The offending input is the HTTP task's body/condition parameter content; the message interpolates the offending value.

Source

Thrown at dolphinscheduler-task-plugin/dolphinscheduler-task-http/src/main/java/org/apache/dolphinscheduler/plugin/task/http/HttpTask.java:263

                .peek((httpProperty) -> {
                    httpProperty.setProp(ParameterUtils.convertParameterPlaceholders(httpProperty.getProp(),
                            ParameterUtils.convert(taskExecutionContext.getPrepareParamsMap())));
                    httpProperty.setValue(ParameterUtils.convertParameterPlaceholders(httpProperty.getValue(),
                            ParameterUtils.convert(taskExecutionContext.getPrepareParamsMap())));
                })
                .collect(Collectors.toMap(HttpProperty::getProp, HttpProperty::getValue));
    }

    private Map<String, Object> getRequestBody() {
        String convertedParams = ParameterUtils.convertParameterPlaceholders(httpParameters.getHttpRequestBody(),
                ParameterUtils.convert(taskExecutionContext.getPrepareParamsMap()));
        JsonNode requestBodyJsonNode = JSONUtils.parseObject(convertedParams, JsonNode.class);
        if (requestBodyJsonNode == null) {
            return null;
        }

        if (!requestBodyJsonNode.isObject()) {
            throw new IllegalArgumentException(String.format("Http request body should be a json object, but got: %s",
                    convertedParams));
        }

        return JSONUtils.parseObject(requestBodyJsonNode.toString(), new TypeReference<Map<String, Object>>() {
        });
    }

    @Override
    public AbstractParameters getParameters() {
        return this.httpParameters;
    }

    public void addDefaultOutput(String response) {
        // put response in output
        Property outputProperty = new Property();
        outputProperty.setProp(String.format("%s.%s", taskExecutionContext.getTaskName(), "response"));
        outputProperty.setDirect(Direct.OUT);
        outputProperty.setType(DataType.VARCHAR);

View on GitHub (pinned to 02eac45a1b)

Solutions

1. Make the request body a valid JSON object (curly-brace map), not an array or plain string
2. Validate the body JSON in the task definition before saving
3. Check placeholder substitution did not mangle the body into invalid JSON

When it happens

Trigger: Thrown at dolphinscheduler-task-plugin/dolphinscheduler-task-http/src/main/java/org/apache/dolphinscheduler/plugin/task/http/HttpTask.java:263 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/dolphinscheduler@02eac45a1b (2026-09-06). Data as JSON: /api/errors/7b97c7752d53c48b. Report an issue: GitHub.