Improve evaluation context to user object mapping

Signed-off-by: Adam Simon <[email protected]>

Author: Adam Simon

libs/shared/config-cat-core/src/lib/context-transformer.spec.ts

@@ -10,9 +10,11 @@ describe('context-transformer', () => {
 
       const user = {
         identifier: context['targetingKey'],
-        country: undefined,
-        custom: {},
         email: undefined,
+        country: undefined,
+        custom: {
+          targetingKey: context['targetingKey']
+        },
       };
 
       expect(transformContext(context)).toEqual(user);
@@ -29,7 +31,11 @@ describe('context-transformer', () => {
         identifier: context['targetingKey'],
         email: context['email'],
         country: context['country'],
-        custom: {},
+        custom: {
+          targetingKey: context['targetingKey'],
+          email: context['email'],
+          country: context['country'],
+        },
       };
 
       expect(transformContext(context)).toEqual(user);
@@ -44,14 +50,15 @@ describe('context-transformer', () => {
       const user = {
         identifier: context['targetingKey'],
         custom: {
+          targetingKey: context['targetingKey'],
           customString: context['customString'],
         },
       };
 
       expect(transformContext(context)).toEqual(user);
     });
 
-    it('map custom property with number to number', () => {
+    it('map custom property with number', () => {
       const context: EvaluationContext = {
         targetingKey: 'test',
         customNumber: 1,
@@ -60,14 +67,15 @@ describe('context-transformer', () => {
       const user = {
         identifier: context['targetingKey'],
         custom: {
-          customNumber: 1,
+          targetingKey: context['targetingKey'],
+          customNumber: context['customNumber'],
         },
       };
 
       expect(transformContext(context)).toEqual(user);
     });
 
-    it('map custom property with boolean to string', () => {
+    it('map custom property with boolean', () => {
       const context: EvaluationContext = {
         targetingKey: 'test',
         customBoolean: true,
@@ -76,7 +84,8 @@ describe('context-transformer', () => {
       const user = {
         identifier: context['targetingKey'],
         custom: {
-          customBoolean: 'true',
+          targetingKey: context['targetingKey'],
+          customBoolean: context['customBoolean'],
         },
       };
 
@@ -95,6 +104,7 @@ describe('context-transformer', () => {
       const user = {
         identifier: context['targetingKey'],
         custom: {
+          targetingKey: context['targetingKey'],
           customObject: JSON.stringify(context['customObject']),
         },
       };
@@ -111,7 +121,8 @@ describe('context-transformer', () => {
       const user = {
         identifier: context['targetingKey'],
         custom: {
-          customArray: ['one', 'two', 'three'],
+          targetingKey: context['targetingKey'],
+          customArray: context['customArray'],
         },
       };
 
@@ -127,6 +138,7 @@ describe('context-transformer', () => {
       const user = {
         identifier: context['targetingKey'],
         custom: {
+          targetingKey: context['targetingKey'],
           customArray: JSON.stringify(context['customArray']),
         },
       };
@@ -154,11 +166,29 @@ describe('context-transformer', () => {
         email: 'email',
         country: 'country',
         custom: {
-          customString: 'customString',
-          customBoolean: 'true',
-          customNumber: 1,
-          customObject: '{"prop1":"1","prop2":2}',
-          customArray: '[1,"2",false]',
+          targetingKey: context['targetingKey'],
+          email: context['email'],
+          country: context['country'],
+          customString: context['customString'],
+          customBoolean: context['customBoolean'],
+          customNumber: context['customNumber'],
+          customObject: JSON.stringify(context['customObject']),
+          customArray: JSON.stringify(context['customArray']),
+        },
+      };
+
+      expect(transformContext(context)).toEqual(user);
+    });
+
+    it('map identifier if targetingKey is not present', () => {
+      const context: EvaluationContext = {
+        identifier: 'test',
+      };
+
+      const user = {
+        identifier: 'test',
+        custom: {
+          identifier: context['identifier'],
         },
       };
 

libs/shared/config-cat-core/src/lib/context-transformer.ts

@@ -2,26 +2,28 @@ import type { EvaluationContext, EvaluationContextValue } from '@openfeature/cor
 import type { IUser as ConfigCatUser, UserAttributeValue } from '@configcat/sdk';
 
 function toUserAttributeValue(value: EvaluationContextValue): UserAttributeValue {
-  if (typeof value === 'string' || typeof value === 'number' || value instanceof Date) {
-    return value;
-  } else if (Array.isArray(value) && value.every((item) => typeof item === 'string')) {
-    return value as ReadonlyArray<string>;
+  // NOTE: The ConfigCat SDK doesn't support objects and non-string arrays as user attribute values
+  // but we special-case these for backward compatibility.
+  if (typeof value === "object"
+    && (!Array.isArray(value) || !value.every((item) => typeof item === 'string'))) {
+    return JSON.stringify(value);
   }
-  return JSON.stringify(value);
-}
 
-function transformCustomContextValues(contextValue: EvaluationContextValue): ConfigCatUser['custom'] {
-  if (typeof contextValue !== 'object' || contextValue === null) {
-    return {};
-  }
+  // NOTE: No need to check for unsupported attribute values as the ConfigCat SDK handles those internally.
+  return value as UserAttributeValue;
+}
 
-  return Object.entries(contextValue).reduce<ConfigCatUser['custom']>(
-    (context, [key, value]) => {
+function transformCustomContextValues(values: Record<string, EvaluationContextValue>): ConfigCatUser["custom"] {
+  let attributes: ConfigCatUser["custom"];
+  for (const [key, value] of Object.entries(values)) {
+    if (value != null) {
       const transformedValue = toUserAttributeValue(value);
-      return transformedValue ? { ...context, [key]: transformedValue } : context;
-    },
-    {} as ConfigCatUser['custom'],
-  );
+      // NOTE: No need to check for `identifier`, `email` and `country` user attributes
+      // as the ConfigCat SDK ignores those as custom user attributes.
+      (attributes ??= {})[key] = transformedValue;
+    }
+  }
+  return attributes;
 }
 
 function stringOrUndefined(param?: unknown): string | undefined {
@@ -33,16 +35,13 @@ function stringOrUndefined(param?: unknown): string | undefined {
 }
 
 export function transformContext(context: EvaluationContext): ConfigCatUser | undefined {
-  const { targetingKey, email, country, ...attributes } = context;
-
-  if (!targetingKey) {
-    return undefined;
-  }
+  const { targetingKey, email, country } = context;
 
   return {
-    identifier: targetingKey,
+    // NOTE: The ConfigCat SDK handles missing or unsupported identifier values.
+    identifier: targetingKey ?? context["identifier"] as string,
     email: stringOrUndefined(email),
     country: stringOrUndefined(country),
-    custom: transformCustomContextValues(attributes),
+    custom: transformCustomContextValues(context),
   };
 }