split-node-serializer

Fetches split definitions and segments from Split.io and serializes them into a
set of strings that the JavaScript SDK can consume.

Installation

Install via npm:

``console
$ npm i @godaddy/split-node-serializer --save
`

Usage

Use this package in your server-side Node.js environment. The serializer exposes:
1. a Poller that periodically requests raw experiment configuration data from Split.io. Requests happen in the background and the poller caches the latest data in local memory.
1. a DataSerializer that reads from the poller's cache, serializes the data, and returns it in a script to be injected into a client's HTML.

$3

Create an instance of Poller and DataSerializer:

`js
const { Poller, DataSerializer } = require('@godaddy/split-node-serializer')

const poller = new Poller({
splitioApiKey: 'YOUR_API_KEY',
pollingRateSeconds: 600,
serializeSegments: false
})

const dataSerializer = new DataSerializer({ poller })
`

The following option properties are available to the Poller:

| Property | Description |
|-------------------------------|-------------|
| splitioApiKey | The Split.io SDK key for the environment your app is running in. (required) |
| pollingRateSeconds | The interval at which to poll Split.io. Defaults to 300 (5 minutes). |
| serializeSegments | Whether or not to fetch segment configuration data. Defaults to false. |

#### Serializing segments

Segments are pre-defined groups of customers that features can be targeted to. More info here.

Note: Requesting serialized segments will increase the size of your response. Segments can be very large if they include all company employees, for example.

$3

#### start

Make an initial request for changes and start polling for raw configuration data
every pollingRateSeconds:

`js
poller.start()
`

#### stop
To stop the poller:

`js
poller.stop()
`

The poller emits an error event on errors from the Split.io API.

#### generateSerializedDataScript

generateSerializedDataScript is an async method that will read the latest data from the cache and return a script
that adds serialized data to the window.__splitCachePreload object. The
serialized data will be used to determine cohort allocations.

generateSerializedDataScript accepts the following arguments:

| Property | Description |
|-------------------------------|-------------|
| splits | Array of strings that, if included, filters the splitsData (Optional) |
| preloadLocation | The property on the window object where the data is stored. Defaults to __splitCachePreload (Optional) |

`js
const serializedDataScript = await dataSerializer.generateSerializedDataScript()

console.log(serializedDataScript)

//
`

Note: Though this is an async method, there will only be a Split.io API call if you have serializeSegments set to true and are passing in a unique splits parameter that this instance's method has not received before.

Testing

Run the linter:

`console
$ npm run lint
`

Run unit tests:

`console
$ npm test
`

Generate a coverage report:

`console
$ npm run coverage
``

License

MIT