OpenAPI Generator Error Handling — Customizing Error Responses and Exception Handling in Generated Code

In this tutorial, you will learn about OpenAPI Generator Error Handling. We cover key concepts, practical examples, and best practices to help you master this topic.

OpenAPI Generator error handling defines standardized error schemas, custom exception hierarchies, and error response mapping that produces consistent, type-safe error handling across all generated SDKs.

What You'll Learn

• Defining reusable error schemas in OpenAPI spec
• Custom exception class generation
• Error response mapping per status code
• Consistent error handling across languages
• Error details and remediation links

Why It Matters

Poor error handling in generated SDKs forces developers to parse raw HTTP responses. Standardized error schemas produce typed exception classes with structured error data. DodaTech's generated SDKs provide typed error classes for every 4xx/5xx response, reducing error handling code by 60%.

flowchart TD
    A["API Error Response"] --> B{"Which status
code?"}
    B -->|"400"| C["ValidationError
(field-level details)"]
    B -->|"401"| D["AuthenticationError
(token hint)"]
    B -->|"403"| E["AuthorizationError
(required scopes)"]
    B -->|"404"| F["NotFoundError"]
    B -->|"429"| G["RateLimitError
(retry-after)"]
    B -->|"5xx"| H["ServerError
(request ID)"]
    C --> I["Generated SDK throws
typed exception"]
    D --> I
    E --> I
    F --> I
    G --> I
    H --> I

What's Next

Combine error handling with {{< ilink "OpenAPI" "OpenAPI Generator Testing" }} for error response contract tests, and review {{< ilink "OpenAPI" "OpenAPI Generator Specification" }} for schema design.