fixes #808 ([Backend] Optimize Custom RPC URL Support for Hackathon Project Idea Generator)

backend/src/generator/generator.service.ts

@@ -1,7 +1,6 @@
 import OpenAI from 'openai';
-import logger from '../utils/logger.js';
-import dotenv from 'dotenv';
 import { cbManager } from '../lib/circuit-breaker/CircuitBreakerManager.js';
+import logger from '../utils/logger.js';
 
 // dotenv.config(); // Skip in Docker Compose - use environment variables instead
 
@@ -34,24 +33,26 @@ export class GeneratorService {
   async generateProjectIdea(
     theme: string,
     techStack: string[],
-    difficulty: string
+    difficulty: string,
+    customRpcUrl?: string
   ): Promise<ProjectIdea> {
     return this.breaker.execute(
       async () => {
         const prompt = `
           As an expert Web3 and Software Architect, generate a unique and innovative hackathon project idea.
-          
+
           Theme: ${theme}
           Technology Stack: ${techStack.join(', ')}
           Target Difficulty: ${difficulty}
-
+          ${customRpcUrl ? `\nIf this project will interact with a blockchain, prefer using the following RPC endpoint: ${customRpcUrl}` : ''}
+
           Return the response in a structured JSON format with the following keys:
           - title: A catchy name for the project.
           - description: A detailed description of the project and its value proposition.
           - keyFeatures: An array of 3-5 core functionalities.
           - recommendedTech: An array of tools and libraries that would be useful.
           - difficulty: The suggested level (Beginner, Intermediate, or Advanced).
-          
+
           Ensure the idea is practical for a 48-hour hackathon but still innovative.
         `;
 

backend/src/routes/generator/generator.routes.ts

@@ -1,10 +1,10 @@
 // @ts-nocheck
+import { randomUUID } from 'crypto';
 import { Request, Response, Router } from 'express';
 import { GeneratorService } from '../../generator/generator.service.js';
-import logger from '../../utils/logger.js';
 import { getRandomProjectIdea, mockProjectIdeas } from '../../generator/mockData.js';
-import { randomUUID } from 'crypto';
 import { storageService } from '../../services/storage/index.js';
+import logger from '../../utils/logger.js';
 
 const router = Router();
 const generatorService = new GeneratorService();
@@ -21,16 +21,35 @@ const slugify = (value: string): string =>
  */
 router.post('/generate', async (req: Request, res: Response) => {
   try {
-    const { theme, techStack, difficulty, persistToStorage, queuedPersist } = req.body;
+    const { theme, techStack, difficulty, persistToStorage, queuedPersist, customRpcUrl } = req.body;
+
+    // Validate optional custom RPC URL
+    if (customRpcUrl) {
+      try {
+        const url = new URL(customRpcUrl);
+        if (url.protocol !== 'http:' && url.protocol !== 'https:') {
+          res.status(400).json({ error: 'customRpcUrl must use http or https' });
+          return;
+        }
+      } catch (err) {
+        res.status(400).json({ error: 'customRpcUrl is not a valid URL' });
+        return;
+      }
+    }
 
     if (!theme || !techStack || !difficulty) {
       res.status(400).json({ error: 'Theme, techStack, and difficulty are required' });
       return;
     }
 
     // Try AI generation first, fallback to mock data if it fails
-    try {
-      const projectIdea = await generatorService.generateProjectIdea(theme, techStack, difficulty);
+      try {
+      const projectIdea = await generatorService.generateProjectIdea(
+        theme,
+        techStack,
+        difficulty,
+        customRpcUrl
+      );
 
       if (persistToStorage) {
         const projectId = `${slugify(theme)}-${Date.now()}-${randomUUID().slice(0, 8)}`;

backend/tests/generator.service.test.ts

@@ -0,0 +1,57 @@
+import { jest } from '@jest/globals';
+
+const mockCreate = jest.fn();
+
+jest.mock('openai', () => {
+  return {
+    default: jest.fn().mockImplementation(() => ({
+      chat: {
+        completions: {
+          create: mockCreate,
+        },
+      },
+    })),
+  };
+});
+
+describe('GeneratorService - custom RPC integration', () => {
+  beforeEach(() => {
+    mockCreate.mockClear();
+  });
+
+  it('passes customRpcUrl into the AI prompt when provided', async () => {
+    process.env.OPENAI_API_KEY = 'test-key';
+
+    const mockResponse = {
+      choices: [
+        {
+          message: {
+            content: JSON.stringify({
+              title: 'RPC Test Project',
+              description: 'Test description',
+              keyFeatures: ['f1'],
+              recommendedTech: ['Node.js'],
+              difficulty: 'Intermediate',
+            }),
+          },
+        },
+      ],
+    };
+
+    mockCreate.mockResolvedValue(mockResponse as never);
+
+    // Dynamic import to ensure mock is applied
+    const mod = await import('../src/generator/generator.service.js');
+    const GeneratorService = mod.GeneratorService;
+    const svc = new GeneratorService();
+
+    const customRpc = 'https://custom-rpc.example:443';
+    const result = await svc.generateProjectIdea('Theme', ['React'], 'Intermediate', customRpc);
+
+    expect(mockCreate).toHaveBeenCalled();
+    const calledArg = mockCreate.mock.calls[0][0];
+    const userMessage = calledArg.messages[1].content;
+    expect(userMessage).toContain(customRpc);
+    expect(result).toHaveProperty('title', 'RPC Test Project');
+  });
+});

frontend/HACKATHON_IDEA_GENERATOR_README.md

@@ -30,6 +30,10 @@ existing [`generatorAPI`](src/lib/api.ts) in `src/lib/api.ts` — no new client
 introduced. `buildGeneratorParams()` maps the UI filters to the request shape the
 endpoint already accepts (`{ theme, techStack, difficulty }`).
 
+The backend endpoint also accepts an optional `customRpcUrl` string in the
+request body; when provided the AI prompt will be instructed to prefer that RPC
+endpoint for any blockchain interactions mentioned in the generated idea.
+
 ## Filtering
 
 - **Difficulty** — `Beginner | Intermediate | Advanced` (matches `ProjectIdea`).