Sample
fastapi 0.141.1: Configure FastAPI behind a reverse proxy prefix with root_path and root_path_in_servers without route matching 404s or broken Swagger UI docs
Verified sample for pypi fastapi 0.141.1: Configure FastAPI behind a reverse proxy prefix with root_path and root_path_in_servers without route matching 404s…
sha256:fc03836e42df24fc9ebcc02153f8212390e8abec2d04d133be4cc5598abd71d4
This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured.
How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people.
MIT-0
Execution evidence
The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.
- Evidence basis
- Signed contract pass
- Verification receipts
- 2
- Signing keys that built it
- 2
Declared environment
python linux x64 python python pip
Verification-run environments
| Environment | Contract | Stages | Run |
|---|---|---|---|
| python 3.12 · linux alpine/x64 · docker ed25519:d91480838ac982c9 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · python@1 |
2026-08-16 |
| python 3.12 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · python@1 |
2026-08-18 |
Case
HOW- Goal
- Configure FastAPI behind a reverse proxy prefix with root_path and root_path_in_servers without route matching 404s or broken Swagger UI docs
- Symbols
-
- fastapi.FastAPI
- root_path
- root_path_in_servers
- fastapi.testclient.TestClient
- starlette.routing.get_route_path
- Environment
- python
- Created
- 2026-08-16T06:22:44Z
Contract
- assert Starlette get_route_path strips root_path from ASGI scope path, dispatching /api/v1/items/42 to @app.get('/items/{item_id}')
- assert defining route decorators with root_path prefix as @app.get('/api/v1/trapped') fails matching and 404s on /api/v1/trapped
- assert a trailing slash on root_path='/api/v1/' prevents prefix stripping in get_route_path, returning 404 on proxied requests
- assert request.url_for automatically includes root_path without manual string concatenation
- assert static app.openapi() contains no servers, while the ASGI GET /openapi.json endpoint dynamically injects [{'url': '/api/v1'}]
- assert FastAPI(root_path_in_servers=False) suppresses OpenAPI servers injection
- assert Swagger UI /docs dynamically configures the JS bundle to fetch /api/v1/openapi.json
- assert mounting a sub-app at /v2 composes root_path to /api/v1/v2 for routing, url_for, and OpenAPI documentation
Files
- NOTES.md
- csx.json
- requirements.txt
- src/__init__.py
- src/app.py
- test/contract.py