Create a user context using the JavaScript (Node) SDK prior to v6

6 min

Create a user for which you can make flag decisions and track events. The user context is returned as a runtime object that is not otherwise persisted. The purpose of this method is to set a user context once, so you do not have to specify the user each time you make a flag decision or track an event. You can define multiple user contexts.

Version

SDK v4.5 and higher

Description

This call creates a user context for flag decisions and events. You can call this method on the Optimizely client instance, even when the instance is not fully configured yet.

Parameters

The following table lists the required and optional parameters:

Parameter	Type	Description
userId required	string	The ID of the user.
attributes\ optional	map	A map of custom key-value pairs specifying attributes for the user that are used for audience targeting. See the following section for more details.

Audience attributes

You can set custom audience attributes for the user, which you can then use to Target audiencesTarget audiences. You can pass strings, numbers, Booleans, and null as custom user attribute values. If you want to target audiences based on the version of your application that they're using, you can also pass in a string formatted as a semantic version, then define a version audience condition in the Optimizely app.

Important During audience evaluation, note that if you don't pass a valid attribute value for a given audience condition, for example, if you pass a string when the audience condition requires a Boolean, or if you forget to pass a value, then that condition is skipped. The SDK logsSDK logs will include warnings when this occurs.

Returns

Returns an OptimizelyUserContext object. For details, see OptimizelyUserContextOptimizelyUserContext.

Example

// Option 1 – Create a user, then set attributes.
const user = optimizely.createUserContext('user123');
user.setAttribute('is_logged_in', false);
user.setAttribute('app_version', '1.3.2');

// Option 2 – Pass attributes when creating the user.
const attributes = {
  is_logged_in: false,
  app_version: '1.3.2'
}

const user = optimizely.createUserContext('user123', attributes);

Source files

The language and platform source files containing the implementation for the JavaScript (Node) SDK are available on GitHub.