feat: added route for learningObjects

backend/src/app.ts

@@ -2,6 +2,8 @@ import express, { Express, Response } from 'express';
 import initORM from './orm.js';
 import themeRoutes from './routes/themes.js';
 import learningPathRoutes from './routes/learningPaths.js'
+import learningObjectRoutes from './routes/learningObjects.js'
+
 
 const app: Express = express();
 const port: string | number = process.env.PORT || 3000;
@@ -15,6 +17,7 @@ app.get('/', (_, res: Response) => {
 
 app.use('/theme', themeRoutes);
 app.use('/learningPath', learningPathRoutes);
+app.use('/learningObject', learningObjectRoutes);
 
 async function startServer() {
     await initORM();

backend/src/config/config.ts

@@ -0,0 +1,9 @@
+// Can be placed in dotenv but found it redundant
+
+// import dotenv from "dotenv";
+
+// Load .env file
+// dotenv.config();
+
+export const DWENGO_API_BASE = "https://dwengo.org/backend/api";
+

backend/src/controllers/learningObjects.ts

@@ -0,0 +1,20 @@
+import { Request, Response } from "express";
+import { getLearningObjectsFromPath } from "../services/learningObjects.js";
+
+export async function getAllLearningObjects(req: Request, res: Response): Promise<void> {
+    try {
+        const { hruid } = req.params;
+        const language = req.query.language as string || "nl"; // Default to Dutch;
+
+        if (!language) {
+            res.status(400).json({ error: "Language query parameter is required." });
+            return;
+        }
+
+        const learningObjects = await getLearningObjectsFromPath(hruid, language);
+        res.json(learningObjects);
+    } catch (error) {
+        console.error("Error fetching learning objects:", error);
+        res.status(500).json({ error: "Internal server error" });
+    }
+}

backend/src/controllers/learningPaths.ts

@@ -1,16 +1,7 @@
 import { Request, Response } from "express";
 import axios from "axios";
 import { themes } from "../data/themes.js";
-import dotenv from "dotenv";
+import { DWENGO_API_BASE } from "../config/config.js";
-
-// Load environment variables
-dotenv.config();
-
-// Get API base URL from environment variables
-const DWENGO_API_BASE = process.env.DWENGO_API_BASE as string;
-if (!DWENGO_API_BASE) {
-    throw new Error("DWENGO_API_BASE is not defined in the .env file");
-}
 
 /**
  * Fetch learning paths for a given list of HRUIDs.

backend/src/routes/learningObjects.ts

@@ -0,0 +1,11 @@
+import express from "express";
+import { getAllLearningObjects } from "../controllers/learningObjects.js";
+
+const router = express.Router();
+
+// arg: hruid learningPath
+// query: language
+// Route to fetch list of learning objects based on hruid of learning path
+router.get("/:hruid", getAllLearningObjects);
+
+export default router;

backend/src/routes/learningPaths.ts

@@ -3,15 +3,20 @@ import { getLearningPathsFromIds, getLearningPathsByTheme, getAllLearningPaths,
 
 const router = express.Router();
 
+// query: language
 // Route to fetch learning paths based on a list of HRUIDs
 router.get("/", getLearningPathsFromIds);
 
+// query: language
 // Route to fetch all possible learning paths
 router.get("/all", getAllLearningPaths);
 
+// query: language
 // Route to fetch learning paths based on a searchterm
 router.get("/search", searchLearningPaths);
 
+// arg: theme id
+// query: language
 // Route to fetch learning paths based on a theme
 router.get("/theme/:theme", getLearningPathsByTheme);
 

backend/src/services/learningObjects.ts

@@ -0,0 +1,67 @@
+import axios from "axios";
+import { DWENGO_API_BASE } from "../config/config.js";
+
+interface LearningObjectNode {
+    _id: string;
+    learningobject_hruid: string;
+    version: number;
+    language: string;
+}
+
+
+export async function getLearningObjectsFromPath(hruid: string, language: string) {
+    try {
+        const learningPathUrl = `${DWENGO_API_BASE}/learningPath/${hruid}/${language}`;
+        const learningPathResponse = await axios.get(learningPathUrl);
+        const nodes = learningPathResponse.data.nodes;
+
+        if (!nodes || nodes.length === 0) {
+            throw new Error("No learning objects found in this learning path.");
+        }
+
+        return await Promise.all(
+            nodes.map(async (node: LearningObjectNode) => {
+                const metadataUrl = `${DWENGO_API_BASE}/learningObject/getMetadata?hruid=${node.learningobject_hruid}&version=${node.version}&language=${language}`;
+                const metadataResponse = await axios.get(metadataUrl);
+
+                const html_url = `${DWENGO_API_BASE}/learningObject/getRaw?hruid=${node.learningobject_hruid}&version=${node.version}&language=${language}`;
+
+                return filterLearningObjectMetadata(metadataResponse.data, html_url);
+            })
+        );
+
+    } catch (error) {
+        console.error("Error fetching learning objects:", error);
+        throw new Error("Failed to fetch learning objects.");
+    }
+}
+
+function filterLearningObjectMetadata(data: any, html_url: String) {
+    return {
+        key: data.hruid,
+                // hruid learningObject (not path)
+        _id: data._id,
+        uuid: data.uuid,
+        version: data.version,
+
+        title: data.title,
+        html_url,
+            // html content object
+        language: data.language,
+        difficulty: data.difficulty,
+        estimated_time: data.estimated_time,
+        available: data.available,
+        teacher_exclusive: data.teacher_exclusive,
+        educational_goals: data.educational_goals,
+                // list with learningObjects
+        keywords: data.keywords,
+                // for search
+        description: data.description,
+                // for search (not an actual description)
+        target_ages: data.target_ages,
+
+        // skos concepts needed ??
+        // content type needed ??
+        // content location ??
+    };
+}