feat: pass cache metadata to getFreshValue

in order to support dynamically changing chage properties while getting the value

fix #25

src/cachified.spec.ts

@@ -716,6 +716,32 @@ describe('cachified', () => {
     expect(await pValue2).toBe('TWO');
   });
 
+  it('supports extending ttl during getFreshValue operation', async () => {
+    const cache = new Map<string, CacheEntry>();
+    const reporter = createReporter();
+    const getValue = (
+      getFreshValue: CachifiedOptions<string>['getFreshValue'],
+    ) =>
+      cachified({
+        cache,
+        ttl: 5,
+        key: 'test',
+        reporter,
+        getFreshValue,
+      });
+
+    expect(
+      await getValue(({ metadata }) => {
+        metadata.ttl = 10;
+        return 'ONE';
+      }),
+    ).toBe('ONE');
+
+    currentTime = 6;
+
+    expect(await getValue(() => 'TWO')).toBe('ONE');
+  });
+
   it('resolves earlier pending values with faster responses from later calls', async () => {
     const cache = new Map<string, CacheEntry>();
     const getValue = (

src/common.ts

@@ -26,9 +26,12 @@ export interface Cache {
   delete: (key: string) => unknown | Promise<unknown>;
 }
 
+interface GetFreshValueContext {
+  metadata: CacheMetadata;
+}
 export const HANDLE = Symbol();
 export type GetFreshValue<Value> = {
-  (): Promise<Value> | Value;
+  (context: GetFreshValueContext): Promise<Value> | Value;
   [HANDLE]?: () => void;
 };
 export const MIGRATED = Symbol();
@@ -72,7 +75,7 @@ export interface CachifiedOptions<Value> {
    *
    * Can be async and must return fresh value or throw.
    *
-   * @type {function(): Promise | Value} Required
+   * @type {function(context): Promise | Value} Required
    */
   getFreshValue: GetFreshValue<Value>;
   /**

src/getFreshValue.ts

@@ -14,7 +14,7 @@ export async function getFreshValue<Value>(
   let value: unknown;
   try {
     report({ name: 'getFreshValueStart' });
-    const freshValue = await getFreshValue();
+    const freshValue = await getFreshValue({ metadata: context.metadata });
     value = freshValue;
     report({ name: 'getFreshValueSuccess', value: freshValue });
   } catch (error) {