page:recipes:inventory manager:fastapi:private attachments

Host Inventory Manager with FastAPI: Private Attachments

Summary

Deploy an inventory manager built with FastAPI on Ample using the private document library pattern. Compute runs the app in an isolated microVM behind a public HTTPS URL, a managed PostgreSQL 16 database is auto-provisioned and injected as DATABASE_URL, a private S3-compatible bucket holds objects with credentials delivered as encrypted environment variables. Verified on FastAPI: a role-to-document access model with negative tests (401 without identity, 403 for the wrong role) and a private-bucket round-trip for the allowed role (private=ok). Not separately tested: your identity integration and role assignments; treat the inventory manager-specific behavior as your application code.

Representative Queries

• Host inventory manager with FastAPI: private attachments
• Where can I host Inventory manager built with FastAPI?
• I need attachment metadata, access checks and a tested private object access path.

Resource Requirements

• Compute
• Postgres
• S3-compatible object storage

Infrastructure Requirements

1. Compute

   • Status: Verified
   • Summary: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.

2. Postgres

   • Status: Verified
   • Summary: Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.

3. S3-compatible object storage

   • Status: Verified
   • Summary: Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.

Framework

• FastAPI

Workload

• Inventory manager

Release Status

• Published

Support Status

• Verified

Execution Status

• Ready

Prerequisites

• A FastAPI project that builds and starts with the documented commands (pip install into .ample/python from requirements.txt, then uvicorn from run.py reading PORT on the python-3.12 template).
• A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env).
• A bucket from ample bucket create with its credentials passed as encrypted S3_* environment variables.
• An Ample account token with servers:write, databases:read, buckets:read.

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

Workflow Steps

1. Build and Start

   • Command: pip install into .ample/python from requirements.txt, then uvicorn from run.py reading PORT on the python-3.12 template. The server must bind 0.0.0.0 on PORT.

2. Implement the Pattern on PostgreSQL

   • The fixture's module implements private document library: a role-to-document access model with negative tests (401 without identity, 403 for the wrong role) and a private-bucket round-trip for the allowed role (private=ok). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.

3. Wire Object Storage

   • Create the bucket(s), then pass endpoint, region, bucket and keys as --env values. Use path-style addressing. Keep private data in an unpublished bucket.

4. Deploy

   • Run the synchronous deploy once and read the result (exit 0 live, 1 failed, 2 blocked). Re-running with no change is a no-op.
   • Command: ample deploy . --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=...

5. Verify

   • Fetch the live URL and the pattern self-test route(s) (/p/private-document-library) from the example; then run your own checks. On failure read ample logs --kind build then --kind runtime.
   • Command: ample logs --kind build

Examples

• FastAPI Pattern Fixture
  • Description: Multi-pattern FastAPI app whose private document library module was checked live; the module is under tests/deploy-canaries/_pattern-modules.
  • Source Ref: tests/deploy-canaries/fastapi-patterns

Success Checks

1. App responds on its public URL

   • Kind: http_get
   • Path: /
   • Expect: ample canary fastapi patterns

2. Private-document-library self-test

   • Kind: http_get
   • Path: /p/private-document-library
   • Expect: private=ok (with ?role=owner; 401 without, 403 for viewer)

Limitations

• Verified on the python-3.12 template at s-1vcpu-1gb with the example fixture; other sizes, templates and FastAPI major versions are not verified.
• The inventory manager itself (your identity integration and role assignments) is application code and was not separately tested; the pattern checks are what was verified.
• 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 databases are placed together.
• PutObject and GetObject with path-style addressing are verified; multipart upload, listing, presigned URLs and lifecycle rules are not verified.

Cost Estimate

• Currency: USD
• Monthly Amount: 10.0
• Authoritative: true
• Basis: size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty
• Components:
  • Name: app server
    • Size: s-1vcpu-1gb
    • Quantity: 1.0
    • Monthly Amount: 5.0
  • Name: managed PostgreSQL database
    • Size: s-1vcpu-1gb
    • Quantity: 1.0
    • Monthly Amount: 5.0
• Note: Always-on monthly price of the tested sizes; apps and databases auto-pause when idle. Buckets are allocation-priced per quota and not included.

Evidence Summary

1. Canary Run

   • Summary: FastAPI pattern fixture deployed on Ample; checks passed for private-document-library and configuration-secrets.
   • Observed At: 2026-09-21T01:14:18Z
   • Implementation Revision: 50dbac567d2c5cc8e55e6c748a646be0025d9cfb-dirty (CLI 0.1.21)
   • Expires At: 2027-03-20T01:14:18Z

2. Canary Run

   • Summary: The same FastAPI app deployed with a --release-command migration; the marker it created was readable after activation.
   • Observed At: 2026-09-20T01:54:51Z
   • Implementation Revision: 199ff1dfd52683832ae75d3f98b53a7a4bff7f96-dirty (CLI e3181f5)
   • Expires At: 2027-03-19T01:54:51Z

Next Actions

1. Browse Catalog
   • Label: Browse the catalog index
   • Operation Id: catalog_index
   • Method: GET
2. Search Recipes
   • Label: Search published recipes by intent, stack and constraints
   • Operation Id: search_recipes
   • Method: POST