RAML (RESTful API Modeling Language) and Swagger (now known as the OpenAPI Specification) are both specifications for documenting and designing RESTful APIs, but they have some differences in their approach and usage. Here are the key differences between RAML and Swagger (OpenAPI):
Origins:
- RAML: RAML was developed by MuleSoft and was initially released in 2013. It was designed with a focus on simplicity and readability.
- Swagger/OpenAPI: Swagger was initially created by SmartBear Software and later donated to the OpenAPI Initiative under the Linux Foundation. It has a broader industry adoption and support.
Format:
- RAML: RAML uses a YAML-based format for describing API specifications.
- Swagger/OpenAPI: Swagger originally used JSON for its API specification, but it has evolved into the OpenAPI Specification, which supports both JSON and YAML formats.
Design Philosophy:
- RAML: RAML promotes a “code-first” approach, where you define the API contract before writing the code. It encourages developers to think about the API structure first.
- Swagger/OpenAPI: Swagger/OpenAPI can be used in both “code-first” and “design-first” approaches. You can start by documenting an existing API or designing the API contract from scratch.
Tooling and Ecosystem:
- RAML: RAML has a smaller ecosystem of tools and libraries compared to Swagger/OpenAPI. However, it still has support for various programming languages and some tooling.
- Swagger/OpenAPI: Swagger/OpenAPI has a vast ecosystem of tools, libraries, and integrations, making it a more popular choice for API development and documentation. It has widespread support in the industry.
Extensibility:
- RAML: RAML supports extensibility through the use of overlays and extensions, allowing you to reuse and extend API specifications.
- Swagger/OpenAPI: OpenAPI also supports extensibility through the use of custom extensions, allowing you to add additional information or metadata to your API documentation.
Validation and Testing:
- RAML: RAML includes built-in validation capabilities, which can be useful for checking whether the API specification adheres to the defined contract.
- Swagger/OpenAPI: Swagger/OpenAPI relies on external tools and libraries for validation and testing, but there are many available options to choose from.
Community and Adoption:
- RAML: While RAML has its user base and community, it is generally smaller compared to the larger community and adoption of Swagger/OpenAPI.
- Swagger/OpenAPI: Swagger/OpenAPI has widespread adoption across various industries and is often considered a standard for API documentation and design.
In summary, both RAML and Swagger/OpenAPI serve the purpose of documenting and designing RESTful APIs, but Swagger/OpenAPI is more widely adopted and has a larger ecosystem of tools and resources. The choice between them often depends on your specific project requirements and your team’s familiarity with the respective specifications.
