django.md
Membership associations: event registration using Django
Summary
A event registration blueprint for membership associations built with Django on Ample. Domain schema: course_groups (chapter_or_program, start_at, end_at): chapters and programs as groups; memberships (course_group_id, member_email, tier, role, renewed_at): members and roles; sessions (course_group_id, starts_at, title, venue): meetings and events; materials (course_group_id, title, object_key, visibility): member resources; events (seq, record_type, record_id, kind, at): application-owned history written in the same transaction. Public information: about, chapters and benefits, public events, join information. Kept out of scope until handling is reviewed: member directory details, dues and payment records. Member directories are personal data; only public events and member-authorized resources are modeled. Technical basis verified on Django: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected).
Infrastructure requirements
- Verified Compute: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.
- Verified 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.
- Verified S3-compatible object storage: 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 createpassed as encrypted S3_* environment variables - A review of which membership associations data classes may be handled at all; this blueprint models public information only
Exact tested configuration
- template:
python-3.12 - runtime:
python - size:
s-1vcpu-1gb - install:
python3 -m pip install --target .ample/python -r requirements.txt - start:
PYTHONPATH=.ample/python:${PYTHONPATH:-} python3 run.py
Steps
Model the membership associations domain. Create the tables course_groups, memberships, sessions, materials, events. Chapters and programs as groups lives in course_groups; keep the sensitive classes (member directory details, dues and payment records) out of this schema.
Workflow step 1. Model sessions with capacity and registrations with status
Workflow step 2. Register transactionally with a capacity check and an event per registration
Workflow step 3. Reject stale concurrent updates
Workflow step 4. Deploy and verify history and conflict handling
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=...Verify. Run the pattern self-test(s) from the example (/p/transactional-workflows) and your own acceptance checks for the membership associations workflow.
ample logs <deployment_id> --kind build
Tested examples
- Django pattern fixture (tests/deploy-canaries/django-patterns): Verified transactional workflows basis for this blueprint.
Success checks
- app responds on its public URL (
/on the live URL, expect ample canary django patterns) - transactional-workflows self-test from the example (
/p/transactional-workflowson the live URL, expect see the pattern fixture checks)
Limitations
- The technical basis (transactional workflows on Django) was verified with the pattern fixture; the membership associations schema and workflow are an original design for this blueprint and were not executed as a separate application.
- No health, financial, privacy or other compliance claim is made. Member directories are personal data; only public events and member-authorized resources are modeled.
- Public content and synthetic examples only until actual data-handling requirements have been reviewed.
- Verified on the python-3.12 template at s-1vcpu-1gb; region, request-duration limits and other sizes are unknown or unverified.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified.
- PutObject and GetObject with path-style addressing are verified; other S3 operations and CDN cache rules are not.
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 transactional workflows checks passed: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected). The blueprint's Membership associations schema and workflow below build on that verified basis and were not separately executed. (expires 2027-03-19T03:31:44Z)
Execution binding
MCP tool ample_deploy (registry mcp:ample_deploy), schema hash 876465fce906da0c observed 2026-09-21T03:19:59.461917+00:00 at revision 49962bcade4f, binding state current, required scopes: servers:write, databases:read, buckets:read.