feat(config-files): add CacheConfigFileContent decorator

Author: Char2sGu

packages/config-files/src/behaviors.ts

@@ -0,0 +1,25 @@
+import { Observable, shareReplay } from 'rxjs';
+
+import { ConfigFileDefinition } from './definition';
+import { ConfigFileLoader } from './loader';
+
+/**
+ * Decorator for {@link ConfigFileLoader}
+ * that caches the loaded configuration objects of each definition.
+ */
+export class CacheConfigFileContent implements ConfigFileLoader {
+  #cache = new Map<
+    ConfigFileDefinition<unknown, unknown>,
+    Observable<unknown>
+  >();
+
+  constructor(private kernel: ConfigFileLoader) {}
+
+  load<T, Schema>(def: ConfigFileDefinition<T, Schema>): Observable<T> {
+    const cached = this.#cache.get(def);
+    if (cached) return cached as Observable<T>;
+    const result$ = this.kernel.load(def).pipe(shareReplay(1));
+    this.#cache.set(def, result$);
+    return result$;
+  }
+}

packages/config-files/src/public-api.ts

@@ -3,6 +3,7 @@ import { defineConfigFile } from './definition';
 /**@deprecated */
 export const defineConfigFileMetadata = defineConfigFile;
 
+export * from './behaviors';
 export * from './definition';
 export * from './loader';
 export * from './parser';