Add notification types as an enum in utils

packages/utils/src/index.ts

@@ -102,3 +102,44 @@ export function sprintf(format: string, ...args: any[]): string {
     }
   })
 }
+/*
+ * Notification types for use with NotificationCenter
+ * Format is EVENT: <list of parameters to callback>
+ *
+ * SDK consumers can use these to register callbacks with the notification center.
+ *
+ *  @deprecated since 3.1.0
+ *  ACTIVATE: An impression event will be sent to Optimizely
+ *  Callbacks will receive an object argument with the following properties:
+ *    - experiment {Object}
+ *    - userId {string}
+ *    - attributes {Object|undefined}
+ *    - variation {Object}
+ *    - logEvent {Object}
+ *
+ *  DECISION: A decision is made in the system. i.e. user activation,
+ *  feature access or feature-variable value retrieval
+ *  Callbacks will receive an object argument with the following properties:
+ *    - type {string}
+ *    - userId {string}
+ *    - attributes {Object|undefined}
+ *    - decisionInfo {Object|undefined}
+ *
+ *  OPTIMIZELY_CONFIG_UPDATE: This Optimizely instance has been updated with a new
+ *  config
+ *
+ *  TRACK: A conversion event will be sent to Optimizely
+ *  Callbacks will receive the an object argument with the following properties:
+ *    - eventKey {string}
+ *    - userId {string}
+ *    - attributes {Object|undefined}
+ *    - eventTags {Object|undefined}
+ *    - logEvent {Object}
+ *
+ */
+export enum NOTIFICATION_TYPES {
+  ACTIVATE = "ACTIVATE:experiment, user_id,attributes, variation, event",
+  DECISION = "DECISION:type, userId, attributes, decisionInfo",
+  OPTIMIZELY_CONFIG_UPDATE = "OPTIMIZELY_CONFIG_UPDATE",
+  TRACK = "TRACK:event_key, user_id, attributes, event_tags, event"
+}