page:recipes:community forum:rails:public profiles

Host community forum with Rails: public profile assets

Deploy a community forum built with Rails 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.

Summary: Verified on Rails: public objects in a published bucket served from the CDN URL, kept separate from private objects in an unpublished bucket that require authorization (private=ok only for the allowed role).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 Rails: public profile assets
• Where can I host Community forum built with Rails?
• I need separate public profile media from private data, with CDN cache rules.

Resource Requirements

• compute
• postgres
• s3-compatible-object-storage
• 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 Rails project that builds and starts with the documented commands (bundle install into vendor/bundle from Gemfile.lock (development and test groups skipped), then Puma via rails server reading PORT on the ruby-3.4 template with RAILS_ENV=production)
• 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

1. Build and start
   bundle install into vendor/bundle from Gemfile.lock (development and test groups skipped), then Puma via rails server reading PORT on the ruby-3.4 template with RAILS_ENV=production. The server must bind 0.0.0.0 on PORT.

2. 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.

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. Publish only the bucket that serves public assets and reference its CDN URL.

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.

5. 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.

Limitations

• Verified on the ruby-3.4 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Rails 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 (quantity: 1.0, monthly amount: 5.0)
• Managed PostgreSQL database: 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.