page:recipes:community forum:flask:public profiles

Host community forum with Flask: public profile assets

Deploy a community forum built with Flask on Ample using the public image delivery 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, and a published bucket serves public assets from the CDN host. Verified on Flask: public objects in a published bucket served from the CDN URL, kept separate from private objects in an unpublished bucket that require authorization (private=ok only for the allowed role). Not separately tested: your image processing and profile-media rules; treat the community forum-specific behavior as your application code.

Representative Queries

Host community forum with Flask: public profile assets
Where can I host Community forum built with Flask?
I need separate public profile media from private data, with CDN cache rules.

Resource Requirements

primitive:compute
primitive:postgres
primitive:s3-compatible-object-storage
primitive:cdn

Infrastructure Requirements

Compute
Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.
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.
S3-compatible object storage
Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.
CDN
The CDN host serves objects from published buckets. It does not front app compute and is not a cache or key-value store.

Prerequisites

A Flask project that builds and starts with the documented commands (pip install into .ample/python from requirements.txt, then waitress from app.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 and a second, published bucket for public assets (CDN_*).
An Ample account token with servers:write, databases:read, buckets:read.

Workflow Steps

Build and start
pip install into .ample/python from requirements.txt, then waitress from app.py reading PORT on the python-3.12 template. The server must bind 0.0.0.0 on PORT.
Implement the pattern on PostgreSQL
The fixture's module implements public image delivery: public objects in a published bucket served from the CDN URL, kept separate from private objects in an unpublished bucket that require authorization (private=ok only for the allowed role). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.
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. Publish only the bucket that serves public assets and reference its CDN URL.

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.

ample deploy . --name  --public --start "python3 app.py" --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=... --env CDN_PUBLIC_URL=...

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

Examples

Flask pattern fixture
Multi-pattern Flask app whose public image delivery module was checked live; the module is under tests/deploy-canaries/_pattern-modules.
- Source Reference: tests/deploy-canaries/flask-patterns

Success Checks

app responds on its public URL
- kind: http_get
- path: /
- expect: ample canary flask patterns
public-media-library self-test
- kind: http_get
- path: /p/public-media-library
- expect: a CDN URL whose content is served publicly
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 Flask major versions are not verified.
The community forum itself (your image processing and profile-media rules) 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.
The CDN serves published-bucket objects only; cache rules, purge, and TTL control are not verified (the fixture sets Cache-Control on upload and versions keys).

Cost Estimate

Currency: USD
Monthly Amount: 10.0
Basis: size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty
- Components:
  - app server: s-1vcpu-1gb, 1.0 quantity, $5.0 monthly
  - managed PostgreSQL database: s-1vcpu-1gb, 1.0 quantity, $5.0 monthly
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

Canary Run
Flask pattern fixture deployed on Ample (pip install into .ample/python from requirements.txt, then waitress from app.py reading PORT on the python-3.12 template); checks passed for public-media-library, private-document-library and configuration-secrets. Pattern proof: public objects in a published bucket served from the CDN URL, kept separate from private objects in an unpublished bucket that require authorization (private=ok only for the allowed role).

Last Verified At: 2026-09-21T01:14:18Z