# Connect Postgres for React Router

Connect a React Router app to PostgreSQL on Ample. Read DATABASE_URL at runtime with pg: when you supply one with --env it is delivered encrypted and takes precedence; when you supply none and the app needs PostgreSQL, Ample auto-provisions a managed PostgreSQL 16 database and injects its connection string.

## Representative Queries
- Connect Postgres for React Router
- Where can I host Connect Postgres built with React Router?
- I need driver setup, connection settings, secret handling and a real connection test.

## Resource Requirements
- **Compute**
- **Postgres**

## Infrastructure Requirements
- **Compute**: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.
- **Postgres**: Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.

## Prerequisites
- pg reading the DATABASE_URL environment variable at runtime
- Either a production DATABASE_URL to pass with --env, or nothing (auto-provision)
- An Ample account token with servers:write and databases:read

## Workflow Steps
1. **Read the URL at runtime**: Open connections from the DATABASE_URL environment variable inside the app; never commit credentials and never connect at build time.
2. **Choose the source of the database**: Pass --env DATABASE_URL=... for an existing database, or omit it to let Ample provision a managed one on first deploy and reuse it on redeploys.
   - Command: `ample deploy . --name  --public`
3. **Test the connection through the app**: Expose a route (/db) that runs a trivial query and returns postgres=ok.
4. **Verify**: Fetch the live URL and run the success checks below. On failure read the build log, then the runtime log, fix the cause and deploy again; do not blind-retry.
   - Command: `ample logs  --kind build`

## Limitations
- Verified on the node-22 template at s-1vcpu-1gb; other templates and sizes are not verified by this recipe.
- Apps auto-pause when idle and wake on the next request; always-on is an operator setting, not a plan feature.

## Cost Estimate
- **Currency**: USD
- **Monthly Amount**: 10.0
- **Foundation**: Size prices from pricing.toml

### Components
- App server (s-1vcpu-1gb): 1.0 - $5.0
- Managed PostgreSQL database (s-1vcpu-1gb): 1.0 - $5.0

### Note
Apps and managed databases auto-pause when idle; the estimate is the always-on monthly price of the tested sizes. Plan quotas and budgets apply.

## Examples
### React Router + PostgreSQL canary
- Description: Auto-provisioned managed database with a real query.
- Source Reference: tests/deploy-canaries/react-router-postgres-app

## Success Checks
- **Description**: Database route reports a live connection
  - **Path**: /db
  - **Expectation**: postgres=ok

## Next Actions
- **Browse the catalog index**
- **Search published recipes by intent, stack and constraints**
- **Prepare a side-effect-free deployment plan for an authorized project**
- **Read the existing agent authentication setup**
- **Browse React Router**
- **Browse Connect app to database**
- **Browse Relational records**