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OpenAPI support in Zuplo

Zuplo natively supports the OpenAPI 3.1 (and is compatible with 3.0) specification standard as the core way to configure the gateway.

When you create a new project you will see a routes.oas.json file. This is your default OpenAPI routing file (oas = 'open api specification').


You can use the Route Designer to build your routes, which will be creating an OpenAPI document in the background for you (check it out in the JSON View).

You can also import an OpenAPI document by clicking on the Open API tab.

Import Open API

This will merge your imported file with any routes you already have in your .oas.json file. By default, operations will be merged by path & method - but you can choose to merge on operationId instead if you prefer.

OpenAPI Workflow#

Having a source of truth when embracing design-first and OpenAPI is critical. Zuplo offers the best workflow for OpenAPI friendly businesses because its support for OpenAPI is native.

You can start your OpenAPI document in Zuplo and export that to other sources, or you can generate your OpenAPI elsewhere (by hand, using, etc) and sync your changes into Zuplo using our import feature.

The import feature will merge changes from an external source-of-truth OpenAPI document and will keep your Zuplo settings intact, while overwriting everything else from your imported OpenAPI docs. This creates a great workflow, whatever toolset you use.

Import OpenAPI dialog

What's more, you can now have more confidence that your OpenAPI represents the truth of your API implementation - because it now drives the configuration of your gateway.


We will soon be shipping support for OpenAPI validation and linting in Zuplo. If you're interested in being an early customer of these features, let us know at

Zuplo extensions#

Zuplo extends the OpenAPI spec using vendor extensions. You will see two vendor extensions:


One below the path property:

"paths": { "/path-0": { "x-zuplo-path": { "pathMode": "url-pattern" }, } }

x-zuplo-path is used to specify the type of path matching you want to use; open-api is the default and uses the standard OpenAPI slugs for tokens (e.g. /pizza/{size}). You can change the pathMode to url-pattern to use the web standards URLPattern approach to path matching which is much more powerful and supports regular expressions.


And another inside the operation, below the method:

"get": { "summary": "New Route", "description": "Lorem ipsum dolor sit amet, **consectetur adipiscing** elit, sed do `eiusmod tempor` incididunt ut labore et dolore magna aliqua.", "x-zuplo-route": { "corsPolicy": "none", "handler": { "export": "urlForwardHandler", "module": "$import(@zuplo/runtime)", "options": { "baseUrl": "" } }, "policies": { "inbound": [] } }, "operationId": "e73d0713-b894-494d-8796-2c50b8634d47" }

x-zuplo-route is where all of your route settings are configured, including policies, handlers, CORS and more.

Other Supported Extensions#

Zuplo also supports other popular extensions in order to better integrate with your existing tooling.


"get": { "summary": "Internal Route", "x-internal": true, "x-zuplo-route": { ... }, }

You can set this property to true in order to hide a route from the Developer Portal. If you are using the OpenAPI Spec Handler, internal routes will not be present in the generated OpenAPI file.

Multiple File Support#

You can have multiple .oas.json files if you wish to break up your route definitions. Note that routes will be executed in document order, based on the .oas.json files being sorted alphabetically.

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