Plugin system overview

Prior art

Swagger UI leans heavily on concepts and patterns found in React and Redux.

If you aren't already familiar, here's some suggested reading:

• React: Quick Start (reactjs.org)
• Redux README (redux.js.org)

In the following documentation, we won't take the time to define the fundamentals covered in the resources above.

Note: Some of the examples in this section contain JSX, which is a syntax extension to JavaScript that is useful for writing React components.

If you don't want to set up a build pipeline capable of translating JSX to JavaScript, take a look at React without JSX (reactjs.org). You can use our system.React reference to leverage React without needing to pull a copy into your project.

The System

The system is the heart of the Swagger UI application. At runtime, it's a JavaScript object that holds many things:

• React components
• Bound Redux actions and reducers
• Bound Reselect state selectors
• System-wide collection of available components
• Built-in helpers like getComponent, makeMappedContainer, and getStore
• References to the React and Immutable.js libraries (system.React, system.Im)
• User-defined helper functions

The system is built up when Swagger UI is called by iterating through ("compiling") each plugin that Swagger UI has been given, through the presets and plugins configuration options.

Presets

Presets are arrays of plugins, which are provided to Swagger UI through the presets configuration option. All plugins within presets are compiled before any plugins provided via the plugins configuration option. Consider the following example:

const MyPreset = [FirstPlugin, SecondPlugin, ThirdPlugin]

SwaggerUI({
  presets: [
    MyPreset
  ]
})

By default, Swagger UI includes the internal ApisPreset, which contains a set of plugins that provide baseline functionality for Swagger UI. If you specify your own presets option, you need to add the ApisPreset manually, like so:

SwaggerUI({
  presets: [
    SwaggerUI.presets.apis,
    MyAmazingCustomPreset
  ]
})

The need to provide the apis preset when adding other presets is an artifact of Swagger UI's original design, and will likely be removed in the next major version.

getComponent

getComponent is a helper function injected into every container component, which is used to get references to components provided by the plugin system.

All components should be loaded through getComponent, since it allows other plugins to modify the component. It is preferred over a conventional import statement.

Container components in Swagger UI can be loaded by passing true as the second argument to getComponent, like so:

getComponent("ContainerComponentName", true)

This will map the current system as props to the component.