[wip] OpenRouter: Add model providers endpoint

src/endpoints/openrouter.js

@@ -4,6 +4,31 @@ import { jsonParser } from '../express-common.js';
 export const router = express.Router();
 const API_OPENROUTER = 'https://openrouter.ai/api/v1';
 
+router.post('/models/providers', jsonParser, async (req, res) => {
+    try {
+        const { model } = req.body;
+        const response = await fetch(`${API_OPENROUTER}/models/${model}/endpoints`, {
+            method: 'GET',
+            headers: {
+                'Accept': 'application/json',
+            },
+        });
+
+        if (!response.ok) {
+            return res.json([]);
+        }
+
+        const data = await response.json();
+        const endpoints = data?.data?.endpoints || [];
+        const providerNames = endpoints.map(e => e.provider_name);
+
+        return res.json(providerNames);
+    } catch (error) {
+        console.error(error);
+        return res.sendStatus(500);
+    }
+});
+
 router.post('/models/multimodal', jsonParser, async (_req, res) => {
     try {
         // The endpoint is available without authentication