refactor(backend): Changed folder structure for learning content services.

backend/src/services/learning-objects/learning-object-provider.ts

@@ -0,0 +1,27 @@
+import {
+    FilteredLearningObject,
+    LearningObjectIdentifier,
+    LearningPathIdentifier
+} from "../../interfaces/learning-content";
+
+export interface LearningObjectProvider {
+    /**
+     * Fetches a single learning object by its HRUID
+     */
+    getLearningObjectById(id: LearningObjectIdentifier): Promise<FilteredLearningObject | null>;
+
+    /**
+     * Fetch full learning object data (metadata)
+     */
+    getLearningObjectsFromPath(id: LearningPathIdentifier): Promise<FilteredLearningObject[]>;
+
+    /**
+     * Fetch only learning object HRUIDs
+     */
+    getLearningObjectIdsFromPath(id: LearningPathIdentifier): Promise<string[]>;
+
+    /**
+     * Obtain a HTML-rendering of the learning object with the given identifier (as a string).
+     */
+    getLearningObjectHTML(id: LearningObjectIdentifier): Promise<string | null>;
+}