1# Cosmos DB Recipe — Node.js — REFERENCE ONLY
2 
3## Cosmos SDK Setup
4 
5### npm Packages
6 
7```bash
8npm install @azure/cosmos @azure/identity
9```
10 
11### Database Module
12 
13Create `src/cosmosClient.js`:
14 
15```javascript
16const { CosmosClient } = require("@azure/cosmos");
17const { DefaultAzureCredential } = require("@azure/identity");
18 
19const client = new CosmosClient({
20  endpoint: process.env.COSMOS_ENDPOINT,
21  aadCredentials: new DefaultAzureCredential(),
22});
23 
24const container = client
25  .database(process.env.COSMOS_DATABASE_NAME)
26  .container(process.env.COSMOS_CONTAINER_NAME);
27 
28module.exports = { container };
29```
30 
31### CRUD Endpoints
32 
33Add to `src/index.js`:
34 
35```javascript
36const { container } = require("./cosmosClient");
37 
38app.get("/api/items", async (req, res) => {
39  const { resources } = await container.items.readAll().fetchAll();
40  res.json(resources);
41});
42 
43app.post("/api/items", async (req, res) => {
44  const { resource } = await container.items.create(req.body);
45  res.status(201).json(resource);
46});
47```
48 
49## Files to Modify
50 
51| File | Action |
52|------|--------|
53| `src/cosmosClient.js` | Create — Cosmos client + container reference |
54| `src/index.js` | Modify — add CRUD endpoints |
55| `package.json` | Modify — add @azure/cosmos, @azure/identity |
56