prepare 3.0.0 release

[LaunchDarklyReleaseBot]

[3.0.0] - 2022-12-07

The latest version of this SDK supports LaunchDarkly's new custom contexts feature. Contexts are an evolution of a previously-existing concept, "users." Contexts let you create targeting rules for feature flags based on a variety of different information, including attributes pertaining to users, organizations, devices, and more. You can even combine contexts to create "multi-contexts."

This feature is only available to members of LaunchDarkly's Early Access Program (EAP). If you're in the EAP, you can use contexts by updating your SDK to the latest version and, if applicable, updating your Relay Proxy. Outdated SDK versions do not support contexts, and will cause unpredictable flag evaluation behavior.

If you are not in the EAP, only use single contexts of kind "user", or continue to use the user type if available. If you try to create contexts, the context will be sent to LaunchDarkly, but any data not related to the user object will be ignored.

For detailed information about this version, please refer to the list below. For information on how to upgrade from the previous version, please read the migration guide.

Added:

• The types LDContext, LDSingleKindContext, and LDMultiKindContext define the new "context" model.
• All SDK methods that took an LDUser parameter now take an LDContext. LDUser is now a subset of LDContext, so existing code based on users will still work.

Changed (breaking changes from 3.x):

• There is no longer such a thing as a secondary meta-attribute that affects percentage rollouts. If you set an attribute with that name in LDContext, it will simply be a custom attribute like any other.
• Evaluations now treat the anonymous attribute as a simple boolean, with no distinction between a false state and an undefined state.
• LDClient.getUser has been replaced with LDClient.getContext.
• privateAttributeNames has been replaced with privateAttributes in LDOptions. Private attributes now allow using attribute references.

Changed (behavioral changes):

• Analytics event data now uses a new JSON schema due to differences between the context model and the old user model.

Removed:

• Removed all types, fields, and methods that were deprecated as of the most recent 3.x release.
• Removed the secondary meta-attribute in LDUser.
• The alias method no longer exists because alias events are not needed in the new context model.
• The autoAliasingOptOut and inlineUsersInEvents options no longer exist because they are not relevant in the new context model.

Deprecated:

• The LDUser object has been deprecated. Support for LDUser is maintained to simplify the upgrade process, but it is recommended to use LDContext in the shape of either LDSingleKindContext or LDMultiKindContext.