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RepreZen API Studio provides best-in-class support for OpenAPI 3.0 editing, documentation, and code generation.  Feature highlights include:

  • Complete editing support for OpenAPI 3.0, with advanced validation and template-driven code assist.
  • Real-time views including Documentation, Diagram and Swagger UI 3.0 
  • Advanced multi-file support throughout the API design lifecycle, including code assist, navigation, documentation, and code generation. 
  • Powerful Code generation including server implementation scaffolds, client SDKs, documentation, and even custom code generators.

Even better, the core OpenAPI stack is open source, built on RepreZen's powerful new KaiZen components:

  • KaiZen OpenAPI Editor is RepreZen's core OpenAPI editor for Eclipse, with template-driven code assist, quick outline navigation, and tons of productivity-boosting features.
  • KaiZen OpenAPI Parser is our high-performance, Java-based parser, validator, and programmable object model for OpenAPI.
  • JSON Overlay is a framework for creating a Java Parser and read/write API for JSON- and YAML-based languages.

Other proprietary and open source components round out the implementation:

  • KaiZen OpenAPI Normalizer (f/k/a Swagger Normalizer) consolidates and simplifies complex multi-file projects into a single document for seamless downstream processing and code generation.
  • OpenAPI-Generator is a new project, based on Swagger Codegen, that provides a comprehensive set of code generators for OpenAPI 3.0.
  • Swagger UI provides interactive real-time documentation with integrated sandbox testing.


How do I create a new OpenAPI v3 spec?

If you're using RepreZen API Studio...

Click the Toolbar button to create a new OpenAPI 3.0 spec.

If you're using KaiZen OpenAPI Editor...

Use the OpenAPI v3 Spec wizard from the KaiZen OpenAPI Editor category:

What's next for OpenAPI 3.0 Support in RepreZen API Studio?

In the near future, we'll be providing an OpenAPI 3.0 compatible mock service, improved validation, and support for new features being introduced to the OpenAPI 3.0 specification.

RepreZen API Studio provides the best available support for OpenAPI 3.0, and you'll see even more OpenAPI innovations from RepreZen.  Watch this space!

The editor for Swagger v2 uses an underlying JSON Schema. There's no official JSON Schema for OpenAPI v3, so what are you using?

We use a modification of the JSON Schema provided by googleapis/gnostic. Thanks to @timburks and @MikeRalphson for the contribution!

KaiZen OpenAPI Parser also provides advanced validation for OpenAPI 3.0, independent of the JSON Schema.