Discloud One‑Click MongoDB Add‑On: Provision, Connect, and Limits

The problem: getting a managed MongoDB instance without leaving the Discloud workflow

When you deploy a Node.js service on Discloud you often need a database quickly. Spinning up a separate MongoDB cluster, handling credentials, and wiring the connection string into your app adds friction and a surface for mis‑configuration. Discloud’s one‑click MongoDB add‑on promises to remove that friction by provisioning a managed instance, generating credentials, and injecting a MONGODB_URI environment variable automatically.

What the add‑on actually does

• Creates a managed MongoDB deployment (versions 4.4 or 5.0).
• Generates a unique username/password pair.
• Exposes the connection string as MONGODB_URI in the linked app’s environment.
• Rotates credentials without downtime – the platform updates the env var for you.
• Provides automated daily backups (7‑day retention on the free tier).

Provisioning from the dashboard

1. Open your app in the Discloud dashboard.
2. Navigate to Add‑ons → MongoDB.
3. Click Add and confirm the plan (free or paid).
4. After a few seconds the MONGODB_URI entry appears under Environment Variables.

Provisioning from the CLI

Run the following command from a terminal where the Discloud CLI is authenticated (requires discloud login first). Replace <app-name> with your actual application slug.

discloud addon add mongodb <app-name>

The CLI prints the generated URI and confirms that the environment variable has been set. This mirrors the dashboard flow and is scriptable for CI pipelines.

Worked example: connecting a Node.js app

Assume a minimal Express service. The only code change required is reading the injected variable.

// server.js
const { MongoClient } = require('mongodb');
const uri = process.env.MONGODB_URI; // injected by Discloud
if (!uri) {
  console.error('MONGODB_URI not set – is the add‑on attached?');
  process.exit(1);
}
const client = new MongoClient(uri);
await client.connect();
console.log('Connected to MongoDB');
// ... use client.db() ...

Deploy the app (e.g., discloud deploy) and watch the logs. A successful connection message confirms that the add‑on is correctly provisioned and reachable.

Verification checklist

• Dashboard: Environment Variables list shows MONGODB_URI with a mongodb:// or mongodb+srv:// scheme.
• CLI: Run discloud env get <app-name> MONGODB_URI – it should return the same string.
• Runtime test: Add a one‑off script that logs process.env.MONGODB_URI and attempts client.connect(). Success = green light.

Trade‑offs and limitations

Aspect	Free tier	Paid plans
Storage	512 MB (shared)	Up to 10 GB, dedicated
Backup retention	7 days	30 days + point‑in‑time recovery
Performance	Throttled under load	Provisioned IOPS, no throttling
Scaling	Manual plan upgrade only	Vertical storage scaling via UI/CLI

If your workload is write‑heavy or you need longer backup history, the free tier will become a bottleneck. The add‑on does not expose replica‑set configuration or custom MongoDB parameters – you get a managed single‑node (or replica‑set on paid) instance with sensible defaults.

Actionable next step

Attach the MongoDB add‑on to a staging app today, run the verification checklist, and measure latency on a realistic write load. If you hit the 512 MB ceiling or see throttling, plan a paid‑tier upgrade before promoting to production. The zero‑downtime credential rotation means you can switch tiers without redeploying code – just change the plan in the dashboard and the MONGODB_URI updates automatically.