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+---
+name: testing-mean003
+description: Test the mean003 MEAN stack web app end-to-end. Use when verifying login, profile, navigation, or MongoDB-related changes.
+---
+
+# Testing mean003
+
+## Prerequisites
+
+- Node.js (tested with v22.12.0)
+- Access to the MongoDB Atlas cluster via `MONGODB_URI` secret
+
+## Devin Secrets Needed
+
+- `MONGODB_URI` — MongoDB Atlas connection string for the sample_mflix database
+
+## Running the App
+
+```bash
+cd /home/ubuntu/repos/mean003
+npm install
+MONGODB_URI="$MONGODB_URI" npm start
+```
+
+The dev server runs on `localhost:3000`. Webpack 4 requires the `--openssl-legacy-provider` flag on Node 17+ (already configured in package.json).
+
+## Test User Setup
+
+Create a test user in the `sample_mflix.users` collection with bcrypt-hashed password:
+
+```javascript
+const { MongoClient } = require('mongodb');
+const bcrypt = require('bcryptjs');
+async function createTestUser() {
+  const client = new MongoClient(process.env.MONGODB_URI);
+  await client.connect();
+  const db = client.db('sample_mflix');
+  const hash = await bcrypt.hash('testpass123', 12);
+  await db.collection('users').insertOne({
+    name: 'Test User',
+    email: 'test@mean003.com',
+    password: hash,
+    secondaryEmail: 'test.backup@mean003.com',
+    phone: '(555) 123-4567',
+    mailingAddress: { street: '123 Main Street', city: 'Springfield', state: 'IL', zip: '62701' }
+  });
+  await client.close();
+}
+```
+
+Credentials: `test@mean003.com` / `testpass123`
+
+**Important:** Clean up the test user after testing by deleting it from the collection.
+
+## Key Testing Flows
+
+### 1. Navigation
+- Visit each page: `/`, `/about`, `/blog`, `/products`, `/profile`
+- Verify nav header appears on all pages with correct links
+- Account Profile link should be positioned upper-right with a user silhouette icon
+
+### 2. Login Redirect
+- Visit `/profile` while logged out → should auto-redirect to `/login?redirect=/profile`
+- Log in with test credentials → should redirect back to `/profile` with user data displayed
+- The old behavior showed a static "not logged in" message; the new behavior auto-redirects
+
+### 3. Profile Form
+- Log in, navigate to `/profile`
+- Form should display: Primary Email, Secondary Email, Phone Number, Mailing Address (Street, City, State, Zip)
+- Edit a field, click "Save Changes" → green "Profile updated successfully" message
+- Refresh page → edited value should persist (data saved to MongoDB)
+
+### 4. Logout
+- Click Logout on profile page → redirects to `/login`
+- Visit `/profile` again → should redirect to login (session cleared)
+
+## Lint & Tests
+
+```bash
+npm run lint   # ESLint — expect 0 errors, 2 warnings (console statements in connection.js)
+npm test       # Mocha — expect 2 passing tests
+```
+
+## Common Issues
+
+- **ERR_OSSL_EVP_UNSUPPORTED**: Already fixed via `cross-env NODE_OPTIONS=--openssl-legacy-provider` in package.json. If it recurs, ensure `cross-env` is installed.
+- **ESLint async/await errors**: `.eslintrc.json` ecmaVersion must be 8+ (ES2017).
+- **Empty profile fields**: If a user has no secondaryEmail/phone/mailingAddress fields in MongoDB, the form shows empty inputs — this is expected behavior.