page:recipes:approval workflow:rails:private attachments

Host approval workflow with Rails: private attachments

Deploy a approval workflow built with Rails 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 Rails: 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 approval workflow-specific behavior as your application code.

Representative Queries

Host approval workflow with Rails: private attachments
Where can I host Approval workflow built with Rails?
I need attachment metadata, access checks and a tested private object access path.

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
An Ample account token with servers:write, databases:read, buckets:read

Workflow Steps

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.
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.
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 Keep private data in an unpublished bucket.
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 --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=...
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

Success Checks

App responds on its public URL (expect: ample canary rails patterns)
Private-document-library self-test (expect: private=ok with ?role=owner; 401 without, 403 for viewer)

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 approval workflow itself (your identity integration and role assignments) is application code and was not separately tested; the pattern checks are what was verified.

Costs Estimate

Monthly Amount: $10.00
App Server: $5.00
Managed PostgreSQL Database: $5.00
Note: Always-on monthly price of the tested sizes; apps and databases auto-pause when idle.

Evidence Summary

Rails pattern fixture deployed on Ample (checks passed for private-document-library and configuration-secrets).
The same Rails app deployed with a --release-command migration.

Last Verified At

2026-09-20T21:55:28Z