Configure S3-compatible access for Starlette

Summary

Object storage client for a Starlette app on Ample. Verified on Starlette: bucket credentials delivered as encrypted S3_* environment variables and a validated PutObject/GetObject round-trip linked to a database row (upload=ok linked=ok). Build and start: pip install into .ample/python from requirements.txt, then uvicorn from run.py reading PORT on the python-3.12 template.

Prerequisites

• A Starlette project (pip install into .ample/python from requirements.txt, then uvicorn from run.py reading PORT on the python-3.12 template)
• A bucket from ample bucket create with credentials passed as encrypted S3_* environment variables
• An Ample account token with servers:write, buckets:read

Workflow Steps

1. Build and start
   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. Create the bucket and pass its credentials
   Create it once with ample bucket create, then pass endpoint, region, bucket and keys with --env; use path-style addressing.
   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=...

3. Verify
   Fetch the live URL and /p/browser-file-uploads on the example; on failure read the build and runtime logs.
   Command: ample logs --kind build

Success Checks

• app responds on its public URL

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

• browser-file-uploads check from the example

  • Kind: http_get
  • Path: /p/browser-file-uploads
  • Expect: see the pattern fixture checks

Limitations

• Verified on the python-3.12 template at s-1vcpu-1gb; other sizes and Starlette major versions are not verified.
• Region, compliance attestations, and request-duration limits are unknown and not claimed.
• PutObject and GetObject with path-style addressing are verified; other S3 operations are not.

Cost Estimate

• Currency: USD
• Monthly Amount: 5.0
• Basis: size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty
• Note: Always-on monthly price of the tested sizes; apps auto-pause when idle. Buckets are allocation-priced per quota and not included.

Examples

• Title: Starlette pattern fixture
  Description: Verified object storage client on Starlette.
  Source Reference: tests/deploy-canaries/starlette-patterns

Infrastructure Requirements

• Primitive: 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.

• Primitive: 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.

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

Input Schema

• Properties:

  • env: Encrypted environment variables (type: array)
  • name: App name (type: string)
  • path: Project directory or ample.toml service (type: string)
  • release_command: Migration command run before activation (type: string)
  • start: Start command (type: string)

• Required: ["env", "name", "path", "start"]

• Type: object

Evidence Summary

• Kind: canary_run
• Summary: Starlette pattern fixture deployed on Ample (pip install into .ample/python from requirements.txt, then uvicorn from run.py reading PORT on the python-3.12 template); for this guide: bucket credentials delivered as encrypted S3_* environment variables and a validated PutObject/GetObject round-trip linked to a database row (upload=ok linked=ok).
• Observed At: 2026-09-21T01:21:36Z
• Implementation Revision: 50dbac567d2c5cc8e55e6c748a646be0025d9cfb-dirty (CLI 0.1.21)
• Expires At: 2027-03-20T01:21:36Z
• Scope: {"checks":["/p/browser-file-uploads"],"template":"python-3.12"}

Last Verified At

• 2026-09-21T01:21:36Z