# Construction contractors: reporting dashboard using Django

## Summary

A reporting dashboard blueprint for construction contractors built with Django on Ample. Domain schema: listings (reference, project_type, location, publishing_status, agency_id): showcase projects with publishing status; agencies (name, license_number, service_region): branches or divisions; vendors (name, trade, agency_id, prequalified): subcontractors and suppliers per branch; reports (agency_id, period, object_key, generated_at): branch progress reports; exports (id, definition, object_key, row_count, generated_at, authorized_role): generated artifacts and who may download them. Public information: published project showcases, services and regions, licenses and insurance summary. Kept out of scope until handling is reviewed: site safety incidents, bid pricing, client contracts. Safety and bid data are confidential; only published showcases and branch reporting are modeled. Technical basis verified on Django: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3).

## Infrastructure requirements

- **Compute**: verified (Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.)
- **Postgres**: verified (Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.)
- **S3-compatible object storage**: verified (Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.)

## Prerequisites

- A Django project (pip install into .ample/python from requirements.txt, then waitress serving project.wsgi from run.py reading PORT on the python-3.12 template)
- A PostgreSQL driver reading DATABASE_URL (auto-provisioned when omitted)
- Bucket credentials from `ample bucket create` passed as encrypted S3_* environment variables
- A review of which construction contractors data classes may be handled at all; this blueprint models public information only

## Steps

1. **Model the construction contractors domain.** Create the tables listings, agencies, vendors, reports, exports. Showcase projects with publishing status lives in listings; keep the sensitive classes (site safety incidents, bid pricing, client contracts) out of this schema.
2. **Workflow step 1.** Model report definitions scoped to the agency
3. **Workflow step 2.** Generate report artifacts from queries and store them with metadata
4. **Workflow step 3.** Authorize downloads (401 without identity)
5. **Workflow step 4.** Deploy and verify an authorized export and the rejected anonymous request
6. **Deploy.** Run the synchronous deploy once and read the result. Re-running with no change is a no-op.

```
   ample deploy . --name <app-name> --public --start "python3 run.py" --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=...
   ```
7. **Verify.** Run the pattern self-test(s) from the example (/p/generated-downloads) and your own acceptance checks for the construction contractors workflow.

```
   ample logs <deployment_id> --kind build
   ```

## Cost estimate

Estimated 10.00 USD per month (size prices from pricing.toml at build revision a1b8c38919e59cd035ebabaced73cf84ece24371).
- app server x1 `s-1vcpu-1gb`: 5.00 USD
- managed PostgreSQL database x1 `s-1vcpu-1gb`: 5.00 USD

Always-on monthly price of the tested sizes; apps and databases auto-pause when idle. Buckets are allocation-priced per quota and not included.

## Verification evidence

- canary_run on 2026-09-20T03:31:44Z at revision `03b6402b1b3e19178985f08ea4033804521d85d4-dirty (CLI b75e104)`: Django pattern fixture deployed on Ample (pip install into .ample/python from requirements.txt, then waitress serving project.wsgi from run.py reading PORT on the python-3.12 template); the generated downloads checks passed: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3).

Last verified: 2026-09-20T03:31:44Z