json Plugin

Overview

The JSON Plugin fetches data from API endpoints during route discovery. Scully uses this data to create a list of routes that contain route parameters.

Usage

Imagine your app has an Angular route configured with the path users/:userId. Scully needs help understanding the route parameter :userId.

The following is an example of how you could use the jsonPlugin to get userIds from your server (localhost:8200) that Scully needs to pre-render the user/:userId routes.

// scully.config.ts
export const config: ScullyConfig = {
  // Add the following to your file
  routes: {
    '/user/:userId': {
      type: 'json',
      userId: {
        url: 'http://localhost:8200/users',
        property: 'id',
      },
    },
  },
};

The above example tells Scully to use the json plugin whenever it finds a route matching /user/:userId. The userId's value contains two pieces of data. First, the url that the JSON plugin should go to get an array of userIds or users. And second, the property of id. When used together, the url returns a list of users, and then the id property is plucked from each user object.

The JSON plugin plucks the provided property name from each of the items in the HandledRoute[] array. In other words, the data array returned by the API, each contain an id property. Therefore, returning a list of userIds instead of a list of users.

JSON Plugin Options

The following describes each of the options available for user with the json plugin.

The following five options are configurable for this plugin:

  • postRenderers
  • url
  • property
  • headers
  • resultsHandler

The following is an example and explanation of each options.

// scully.config.ts
export const config: ScullyConfig = {
  routes: {
    '/users/:userId': {
      type: 'json',
      /**
       * postRenderers: postRenderers[]
       *
       * This options allows you to configure postRenderers for this route returned
       * by this `/users/:userId` plugin.
       */
      postRenderers: [],
      userId: {
        /**
         * url: string
         *
         * An API that returns a response containing the data (preferribly an array)
         * needed for all `userId`s in the system.
         */
        url: 'https://my-api.com/users',
        /**
         * property: string
         *
         * If the `url` returns an array of objects, use the `property` to provide the
         * name of the property that can be used to pluck the `userId` from each item.
         * If the APi returns a list of items using the `id` property for the `userId`,
         * the following config would pluck the `id` property off of each user object.
         */
        property: 'id',
        /**
         * headers: {[key:string]:any}
         *
         * If the `url` API requires specific headers, you can provide those here. The
         * header name is the key, and the header value is the value.
         */
        headers: {
          'API-KEY': '0123456789',
        },
        /**
         * resultsHandler: (response: any) => any[]
         *
         * If the `url` returns an object, use the `resultsHandler` to map that object
         * into an array of objects/ids.
         *
         * In the following example, the server returned an object where the users were
         * nested inside of the `response.data` property. So the resultsHandler returns
         * `response.data.users`.
         */
        resultsHandler: (response) => response.data.users,
      },
    },
  },
};