OpenAPITools/openapi-generator · error · RuntimeException

Empty method name (operationId) not allowed

Error message

Empty method name (operationId) not allowed

What it means

Error "Empty method name (operationId) not allowed" thrown in OpenAPITools/openapi-generator.

Source

Thrown at modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppTizenClientCodegen.java:309

    @Override
    public String toVarName(String name) {
        String paramName = name.replaceAll("[^a-zA-Z0-9_]", "");
        if (name.length() > 0) {
            // additionalProperties name is "" so name.length() == 0
            paramName = Character.toLowerCase(paramName.charAt(0)) + paramName.substring(1);
        }
        if (isReservedWord(paramName)) {
            return escapeReservedWord(paramName);
        }
        return paramName;
    }

    @Override
    public String toOperationId(String operationId) {
        // throw exception if method name is empty
        if (StringUtils.isEmpty(operationId)) {
            throw new RuntimeException("Empty method name (operationId) not allowed");
        }

        // method name cannot use reserved keyword, e.g. return$
        if (isReservedWord(operationId)) {
            operationId = escapeReservedWord(operationId);
        }

        // add_pet_by_id => addPetById
        return camelize(operationId, LOWERCASE_FIRST_LETTER);
    }

    /**
     * Output the Getter name for boolean property, e.g. getActive
     *
     * @param name the name of the property
     * @return getter name based on naming convention
     */
    @Override

View on GitHub (pinned to fcec517be3)

Solutions

1. Provide a non-empty operationId for every operation in the OpenAPI spec.

When it happens

Trigger: Thrown when an operation in the OpenAPI spec has an empty or missing operationId while generating a C++ Tizen client. Provide a non-empty operationId for every operation.

Common situations: See trigger scenarios.

AI-assisted analysis of OpenAPITools/openapi-generator@fcec517be3 (2026-08-22). Data as JSON: /api/errors/5ab5a31932397041. Report an issue: GitHub.