## Connect Postgres for Astro

### Summary
Connect an Astro 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.

### 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

### Input Schema
- **env**: Encrypted environment variables as KEY=value; secret values are never stored in ample.toml.
    - Items: Pattern: `^[A-Z][A-Z0-9_]*=.*$`
    - Max items: 50
- **name**: App name (lowercase, digits, and dashes).
    - Max length: 63
    - Min length: 1
    - Pattern: `^[a-z0-9-]+$`
- **path**: Project directory to deploy, or one service name from ample.toml.
    - Max length: 512
    - Min length: 1
- **size**: VM size; omit to let Ample pick a runtime-safe size.
    - Enum: ["s-1vcpu-256mb", "s-1vcpu-1gb", "s-1vcpu-2gb", "s-2vcpu-2gb", "s-2vcpu-4gb"]
- **start**: Start command override when detection cannot infer it.
    - Max length: 512

### 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`

### Examples
- **Astro + PostgreSQL canary**: Auto-provisioned managed database with a real query.
    - Source Reference: `tests/deploy-canaries/astro-postgres-app`

### Success Checks
- Database route reports a live connection.
    - Kind: `http_get`
    - Path: `/db`
    - Expect: `postgres=ok`

### Limitations
- Verified on the node-22 template at s-1vcpu-1gb; other templates and sizes are not verified by this recipe.
- Region, compliance attestations and request-duration limits are unknown and not claimed.
- Apps auto-pause when idle and wake on the next request; always-on is an operator setting, not a plan feature.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified.
- Apps and their managed databases are placed together; cross-node shared databases are unsupported.

### Cost Estimate
- **Currency**: USD
- **Monthly Amount**: 10.0
- **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.