feat: implement tracking as per spec

Signed-off-by: Todd Baert <todd.baert@dynatrace.com>

packages/angular/angular.json

@@ -39,6 +39,7 @@
   "cli": {
     "schematicCollections": [
       "@angular-eslint/schematics"
-    ]
+    ],
+    "analytics": false
   }
 }

packages/server/src/client/client.ts

@@ -8,12 +8,14 @@ import {
 import { Features } from '../evaluation';
 import { ProviderStatus } from '../provider';
 import { ProviderEvents } from '../events';
+import { Tracking } from '../tracking';
 
 export interface Client
   extends EvaluationLifeCycle<Client>,
     Features,
     ManageContext<Client>,
     ManageLogger<Client>,
+    Tracking,
     Eventing<ProviderEvents> {
   readonly metadata: ClientMetadata;
   /**

packages/server/src/client/internal/open-feature-client.ts

@@ -9,6 +9,7 @@ import {
   HookContext,
   JsonValue,
   Logger,
+  OccurrenceDetails,
   OpenFeatureError,
   ProviderFatalError,
   ProviderNotReadyError,
@@ -221,6 +222,10 @@ export class OpenFeatureClient implements Client {
     return this.evaluate<T>(flagKey, this._provider.resolveObjectEvaluation, defaultValue, 'object', context, options);
   }
 
+  track(occurrenceKey: string, context: EvaluationContext, occurrenceDetails: OccurrenceDetails): void {
+    return this._provider.track?.(occurrenceKey, context, occurrenceDetails);
+  }
+
   private async evaluate<T extends FlagValue>(
     flagKey: string,
     resolver: (

packages/server/src/index.ts

@@ -5,4 +5,5 @@ export * from './open-feature';
 export * from './transaction-context';
 export * from './events';
 export * from './hooks';
+export * from './tracking';
 export * from '@openfeature/core';

packages/server/src/provider/provider.ts

@@ -1,4 +1,12 @@
-import { CommonProvider, EvaluationContext, JsonValue, Logger, ResolutionDetails, ServerProviderStatus } from '@openfeature/core';
+import {
+  CommonProvider,
+  EvaluationContext,
+  JsonValue,
+  Logger,
+  OccurrenceDetails,
+  ResolutionDetails,
+  ServerProviderStatus,
+} from '@openfeature/core';
 import { Hook } from '../hooks';
 
 export { ServerProviderStatus as ProviderStatus };
@@ -57,4 +65,12 @@ export interface Provider extends CommonProvider<ServerProviderStatus> {
     context: EvaluationContext,
     logger: Logger,
   ): Promise<ResolutionDetails<T>>;
+
+  /**
+   * Track a thing
+   * @param occurrenceKey
+   * @param context
+   * @param occurrenceDetails
+   */
+  track?(occurrenceKey: string, context: EvaluationContext, occurrenceDetails: OccurrenceDetails): void;
 }

packages/server/src/tracking/index.ts

@@ -0,0 +1 @@
+export * from './tracking';

packages/server/src/tracking/tracking.ts

@@ -0,0 +1,12 @@
+import { EvaluationContext, OccurrenceDetails } from '@openfeature/core';
+
+export interface Tracking {
+
+  /**
+   * Track a thing
+   * @param occurrenceKey
+   * @param context
+   * @param occurrenceDetails
+   */
+  track(occurrenceKey: string, context: EvaluationContext, occurrenceDetails: OccurrenceDetails): void;
+}

packages/shared/src/evaluation/context.ts

@@ -1,4 +1,4 @@
-import { PrimitiveValue } from './evaluation';
+import { PrimitiveValue } from '../types';
 
 export type EvaluationContextValue =
   | PrimitiveValue

packages/shared/src/evaluation/evaluation.ts

@@ -1,13 +1,6 @@
-export type FlagValueType = 'boolean' | 'string' | 'number' | 'object';
-
-export type PrimitiveValue = null | boolean | string | number;
-export type JsonObject = { [key: string]: JsonValue };
-export type JsonArray = JsonValue[];
+import { JsonValue } from '../types/structure';
 
-/**
- * Represents a JSON node value.
- */
-export type JsonValue = PrimitiveValue | JsonObject | JsonArray;
+export type FlagValueType = 'boolean' | 'string' | 'number' | 'object';
 
 /**
  * Represents a JSON node value, or Date.

packages/shared/src/index.ts

@@ -7,4 +7,5 @@ export * from './logger';
 export * from './provider';
 export * from './evaluation';
 export * from './type-guards';
+export * from './tracking';
 export * from './open-feature';

packages/shared/src/tracking/index.ts

@@ -0,0 +1 @@
+export * from './occurrence';

packages/shared/src/tracking/occurrence.ts

@@ -0,0 +1,20 @@
+import { PrimitiveValue } from '../types';
+
+
+export type OccurrenceValue =
+  | PrimitiveValue
+  | Date
+  | { [key: string]: OccurrenceValue }
+  | OccurrenceValue[];
+
+/**
+ * A container for arbitrary contextual data that can be used as a basis for dynamic evaluation
+ */
+export type OccurrenceDetails = {
+  /**
+   * A string uniquely identifying the subject (end-user, or client service) of a flag evaluation.
+   * Providers may require this field for fractional flag evaluation, rules, or overrides targeting specific users.
+   * Such providers may behave unpredictably if a targeting key is not specified at flag resolution.
+   */
+  value?: number;
+} & Record<string, OccurrenceValue>;

packages/shared/src/types/index.ts

@@ -1,2 +1,3 @@
 export * from './metadata';
-export * from './paradigm';
+export * from './paradigm';
+export * from './structure';

packages/shared/src/types/structure.ts

@@ -0,0 +1,7 @@
+export type PrimitiveValue = null | boolean | string | number;
+export type JsonObject = { [key: string]: JsonValue };
+export type JsonArray = JsonValue[];
+/**
+ * Represents a JSON node value.
+ */
+export type JsonValue = PrimitiveValue | JsonObject | JsonArray;

packages/web/src/client/client.ts

@@ -2,8 +2,14 @@ import { ClientMetadata, EvaluationLifeCycle, Eventing, ManageLogger } from '@op
 import { Features } from '../evaluation';
 import { ProviderStatus } from '../provider';
 import { ProviderEvents } from '../events';
+import { Tracking } from '../tracking';
 
-export interface Client extends EvaluationLifeCycle<Client>, Features, ManageLogger<Client>, Eventing<ProviderEvents> {
+export interface Client
+  extends EvaluationLifeCycle<Client>,
+    Features,
+    ManageLogger<Client>,
+    Eventing<ProviderEvents>,
+    Tracking {
   readonly metadata: ClientMetadata;
   /**
    * Returns the status of the associated provider.

packages/web/src/client/internal/open-feature-client.ts

@@ -9,6 +9,7 @@ import {
   HookContext,
   JsonValue,
   Logger,
+  OccurrenceDetails,
   OpenFeatureError,
   ProviderFatalError,
   ProviderNotReadyError,
@@ -179,6 +180,14 @@ export class OpenFeatureClient implements Client {
     return this.evaluate<T>(flagKey, this._provider.resolveObjectEvaluation, defaultValue, 'object', options);
   }
 
+  track(occurrenceKey: string, occurrenceDetails: OccurrenceDetails): void {
+    const context = {
+      ...OpenFeature.getContext(this?.options?.domain),
+    };
+
+    return this._provider.track?.(occurrenceKey, context, occurrenceDetails);
+  }
+
   private evaluate<T extends FlagValue>(
     flagKey: string,
     resolver: (flagKey: string, defaultValue: T, context: EvaluationContext, logger: Logger) => ResolutionDetails<T>,

packages/web/src/index.ts

@@ -4,4 +4,5 @@ export * from './evaluation';
 export * from './open-feature';
 export * from './events';
 export * from './hooks';
+export * from './tracking';
 export * from '@openfeature/core';

packages/web/src/provider/provider.ts

@@ -1,4 +1,4 @@
-import { ClientProviderStatus, CommonProvider, EvaluationContext, JsonValue, Logger, ResolutionDetails } from '@openfeature/core';
+import { ClientProviderStatus, CommonProvider, EvaluationContext, JsonValue, Logger, OccurrenceDetails, ResolutionDetails } from '@openfeature/core';
 import { Hook } from '../hooks';
 
 export { ClientProviderStatus as ProviderStatus };
@@ -71,4 +71,12 @@ export interface Provider extends CommonProvider<ClientProviderStatus> {
     context: EvaluationContext,
     logger: Logger,
   ): ResolutionDetails<T>;
+
+  /**
+   * Track a thing
+   * @param occurrenceKey
+   * @param context
+   * @param occurrenceDetails
+   */
+    track?(occurrenceKey: string, context: EvaluationContext, occurrenceDetails: OccurrenceDetails): void;
 }

packages/web/src/tracking/index.ts

@@ -0,0 +1 @@
+export * from './tracking';

packages/web/src/tracking/tracking.ts

@@ -0,0 +1,11 @@
+import { OccurrenceDetails } from '@openfeature/core';
+
+export interface Tracking {
+
+  /**
+   * Track a thing
+   * @param occurrenceKey
+   * @param occurrenceDetails
+   */
+  track(occurrenceKey: string, occurrenceDetails: OccurrenceDetails): void;
+}