# LaunchDarkly

[LaunchDarkly](https://launchdarkly.com/) is a popular feature management platform that offers cutting-edge A/B testing and experimentation functionalities. It lets you efficiently automate and manage feature flags and improve overall product workflow and software quality.

RudderStack supports LaunchDarkly as a destination to which you can seamlessly send your data for flag management.

## Connection compatibility

{{< destination-config >}}

{{< info >}}
In the web device mode integration, that is, using [JavaScript SDK]({{< ref "sources/event-streams/sdks/rudderstack-javascript-sdk/_index.md" >}}) as a source, RudderStack loads the LaunchDarkly native SDK from the`https://unpkg.com/` domain. 

Based on your website's content security policy, you might need to [allowlist this domain]({{< ref "sources/event-streams/sdks/rudderstack-javascript-sdk/load-js-sdk.md#allowlist-destination-domain" >}}) to load the LaunchDarkly SDK successfully.
{{< /info >}}

## Get started

Once you have confirmed that the source platform supports sending events to LaunchDarkly, follow these steps:

1. From your [RudderStack dashboard](https://app.rudderstack.com/), add a source. Then, from the list of destinations, select **LaunchDarkly**.
2. Assign a name to the destination and click **Continue**.

### Connection settings

To successfully configure LaunchDarkly as a destination, you will need to configure the following settings:

{{< image src="images/event-stream-destinations/launchdarkly-connection-settings.webp" alt="LaunchDarkly connection settings" >}}

* **Client-side ID**: Enter the client-side ID of your LaunchDarkly project.

{{< info >}}
For more information on getting the LaunchDarkly client-side ID, refer to the [FAQ]({{< ref "#faq" >}}) section below.
{{< /info >}}

## Identify

The [`identify`]({{< ref "event-spec/standard-events/identify.md" >}}) call lets you create or update a user in LaunchDarkly.

{{< warning >}}
You must call `identify` before making any `track` or `alias` calls.
{{< /warning >}}

A sample `identify` call is as shown below:

```javascript
rudderanalytics.identify(
  "1hKOmRA4GRlm", {
    anonymous: false,
    avatar: "https://avatarfiles.alphacoders.com/837/83744.jpg",
    country: "USA",
    custom: {
      favourite_color: "black"
    },
    email: "alex@example.com",
    firstName: "Alex",
    ip: "12.23.34.45",
    lastName: "Keener",
    name: "Alex Keener",
    privateAttributeNames: ["avatar", "country"],
    secondary: "abcd21234"
  }
);
```

### LaunchDarkly key

RudderStack assigns the `userId` to LaunchDarkly's `key` field to uniquely identify a user.

{{< info >}}

`key` is the only required field in LaunchDarkly's `identify` call. If no unique identifier is provided, RudderStack will automatically assign `anonymousId` as `key`.
{{< /info >}}

### Supported traits

The following table lists the supported fields for the `traits` object in the `identify` call:

| Field | Type | Presence | Description | 
|:------|:-----|:---------|:-------------|
| `anonymous`    | Boolean | Optional | Must be set to `true`.  |
| `avatar` | String | Optional | User's avatar image URL. |
| `country` | String | Optional | Country associated with the user. |
| `custom` | Object | Optional | Additional attributes associated with the user. |
| `email` | String | Optional | User's email address. |
| `firstName` | String | Optional | User's first name. |
| `ip` | String | Optional | User's IP address. |
| `lastName` | String | Optional | User's last name. |
| `name` | String | Optional | User's full name. |
| `privateAttributeNames` | String Array | Optional | List of attribute names (built-in or custom) marked as private and not sent to LaunchDarkly as analytics events. |
| `secondary` | String | Optional | User's secondary identifier. |

{{< info >}}
If you have chosen to bucket the users by a specific attribute, the `secondary` field can be used to further distinguish the users who are otherwise identical as per that attribute. 
{{< /info >}}

## Track

The [`track`]({{< ref "event-spec/standard-events/track.md" >}}) call lets you record user events and send them to LaunchDarkly as custom conversion metrics for your experiments.

{{< warning >}}
As mentioned above, you must call `identify` before sending any `track` events to LaunchDarkly.
{{< /warning >}}

A sample `track` call is as shown:

```javascript
rudderanalytics.track("Test Event", {
  foo: "bar"
});
```

## Alias

The [`alias`]({{< ref "event-spec/standard-events/alias.md" >}}) call lets you merge different identities of a known user. You can explicitly change the identity of a user via this call.

A sample `alias` call is shown below:

```javascript
rudderanalytics.alias("newUserId","userId");
```

## FAQ 

#### Where do I get the LaunchDarkly Client-side ID?

To get your LaunchDarkly client-side ID, follow these steps:

1. Log into your [LaunchDarkly dashboard](https://app.launchdarkly.com/).
2. Select your project:

{{< image src="images/event-stream-destinations/launchdarkly-projects.webp" alt="LaunchDarkly projects" >}}

3. Then, navigate to **Account settings** > **Projects**.
4. You will see the client-side ID for your project here.

{{< image src="images/event-stream-destinations/launchdarkly-clientsideID.webp" alt="LaunchDarkly client-side ID" >}}