FastAPI

The public FastAPI example uses the Python SDK directly inside the service boundary that owns authorization, tenant scope, before/after state, and the mutation. The adapters/fastapi directory describes future adapter intent; it is not presented here as a finished installable package.

Run the governed CRUD service

git clone https://github.com/getveritio/veritio.git
git -C veritio checkout c4100ee7b678d0c6b227c67ae6ea1d8a1f373967
cd veritio/examples/fastapi-governed-crud
python3 -m venv .venv
. .venv/bin/activate
pip install -e .
PYTHONPATH=../../sdks/python/src:. uvicorn app.main:app --reload --port 8010

The service uses fixed local identities tenant_demo and user_demo so it runs without an authentication provider. Those constants are demonstration context, not a production tenant-resolution strategy.

Create and inspect evidence

curl -X POST http://localhost:8010/projects \
  -H 'content-type: application/json' \
  -d '{"name":"Retention inbox"}'

curl http://localhost:8010/evidence

The mutation creates a governed-action draft, appends its audit and edge inputs to local hash-chained records, and binds the resulting record hashes into an EvidenceCommit. The evidence response returns the audit, edge, and commit chains plus verification status for all three.

Project display names are not stored in metadata. The example records a stable projectNameHash alongside stable IDs and governed fields.

Follow a mutation through the code

1. FastAPI validates the request body.
2. The service resolves actor and tenant from server-owned state.
3. It captures the previous project state.
4. create_governed_action_draft produces portable event and edge inputs for the before/after change.
5. The application applies the mutation and appends local evidence.
6. It creates an EvidenceCommit over the exact persisted record hashes.
7. GET /evidence verifies audit records, edge records, and commit membership.

A production application must decide how steps 5 and 6 become atomic or recoverable. A transactional outbox is appropriate when the business row and evidence delivery cannot be committed in one store operation.

Run the broader lifecycle

curl -X POST http://localhost:8010/scenarios/governed-lifecycle

This records auth session context, organization and membership events, consent, a data-subject request, export evidence, retention-policy evidence, processor-transfer relationships, and EvidenceCommit membership. It is useful for inspecting how templates and graph edges compose without implying that these records perform the governed workflows themselves.

Verify with the upstream tests

cd veritio/examples/fastapi-governed-crud
PYTHONPATH=../../sdks/python/src:. python3 -m unittest discover -s tests

The suite covers CRUD, chain verification, commit membership, country/region security context, canonical plan hashing, consent/DSAR/export/retention helpers, and graph relations.

Production boundary

Do not accept tenant or actor IDs from request bodies without authorization. Do not claim a completed change when the business mutation failed. Replace the in-memory collections with durable application and evidence stores, and define recovery when only one side of the operation commits.

Review the Python SDK boundaries and evidence graph model before adapting the example.