feat: allowing for customKeyFunction in higher-order function

README.md

@@ -101,6 +101,9 @@ The options available are:
   - `executionTime`: The execution time of the current function execution in milliseconds.
   - `args`: The arguments passed to the current function.
   - `timeFrameCacheRecords`: The cache records of the last `timeFrame` milliseconds.
+- `customKeyFunction` (_optional_): A function to generate a custom key for every cache record.  
+  The function receives the arguments passed to the current function and should return a string.  
+  If not passed, the key will be generated based on an internal algorithm that considers the arguments passed to the function.
 - `millisecondThreshold` (_optional_): The threshold in milliseconds to be considered for the condition checks. If not passed, this criteria will be ignored.
 - `requestsThreshold` (_optional_): The number of requests to be considered for the condition checks. Default: `1`.
 - `expirationMode` (_optional_): The expiration mode to use. Default: `default`.

src/index.test.ts

@@ -222,6 +222,22 @@ describe('Higher-Order Function', () => {
     await sleep(TTL + EXECUTION_MARGIN);
     expect(eventHits.get('onCacheHit')).toBe(1);
   });
+
+  it('should allow for custom getDataCacheKey functions', async () => {
+    const mockFn = jest.fn();
+    const wrappedMockFn = cacheCandidate(mockFn, {
+      customKeyFunction: (args) => {
+        return 'custom-key';
+      },
+      events: {
+        onCacheSet: ({key}) => {
+          expect(key).toBe('custom-key');
+        }
+      }
+    });
+    wrappedMockFn(1);
+    await sleep(TTL + EXECUTION_MARGIN);
+  });
 });
 
 describe('Library-wide Conditions', () => {

src/lib.ts

@@ -111,7 +111,7 @@ export function cacheCandidate<T extends (...args: any[]) => Promise<any>>(
   return function cacheCandidateWrapper(...args: Parameters<T>): ReturnType<T> {
     return letsCandidate({
       options,
-      key: getDataCacheKey([uniqueIdentifier, JSON.stringify(args)]),
+      key: _options.customKeyFunction ? _options.customKeyFunction(args) : getDataCacheKey([uniqueIdentifier, JSON.stringify(args)]),
       timeoutCache,
       runningQueryCache,
       timeframeCache,

src/models.ts

@@ -17,6 +17,7 @@ export interface CacheCandidateInputOptions {
   ttl?: number;
   timeFrame?: number;
   candidateFunction?: (CandidateFunctionOptions) => boolean;
+  customKeyFunction?: (args: any) => string;
   millisecondThreshold?: number;
   requestsThreshold?: number;
   expirationMode?: 'default' | 'timeout-only' | 'eject';