Host Asset Library with Rails: Data Exports

Summary

Deploy a asset library built with Rails on Ample using the generated downloads 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: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3). Not separately tested: your export formats, retention policy and entitlement model; treat the asset library-specific behavior as your application code.

Representative Queries

• Host asset library with Rails: data exports
• Where can I host Asset library built with Rails?
• I need a scoped export format, artifact generation and authorized download procedure.

Parent IDs

• workload:asset-library
• stack:framework-rails
• pattern:generated-downloads
• intent:deploy-web-app

Resource Requirements

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

Infrastructure Requirements

1. Compute
   • 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
   • 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
   • Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.

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.

Tested Configuration

• Template: ruby-3.4
• Runtime: ruby
• Size: s-1vcpu-1gb
• Install: bundle config set --local path vendor/bundle && bundle config set --local without 'development test' && bundle install
• Start: bundle exec rails server -b 0.0.0.0 -p $PORT

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 generated downloads: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3). 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.

   ample deploy . --name  --public --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/generated-downloads) from the example; then run your own checks. On failure read ample logs --kind build then --kind runtime.

   ample logs  --kind build
   

Examples

• Rails Pattern Fixture: Multi-pattern Rails app whose generated downloads module was checked live; the module is under tests/deploy-canaries/_pattern-modules.

Success Checks

1. App Responds on Its Public URL

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

2. Generated-Downloads Self-Test

   • Kind: http_get
   • Path: /p/generated-downloads
   • Expect: export=ok rows=3 (with ?token=...; 401 without)

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 asset library itself (your export formats, retention policy and entitlement model) 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.

Cost Estimate

• Currency: USD
• Monthly Amount: 10.0
• Components:
  1. App Server:
     • Size: s-1vcpu-1gb
     • Quantity: 1.0
     • Monthly Amount: 5.0
  2. 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

• Canary Run: Rails pattern fixture deployed on Ample (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); checks passed for generated-downloads and configuration-secrets. Pattern proof: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3).
• Latest Verified: 2026-09-20T21:55:28Z

MCP Binding

• Registry Ref: mcp:ample_deploy
• Tool Name: ample_deploy
• Binding State: current

Unknowns

• Region availability is unknown until a verified region fact is recorded.
• Compliance attestations are unknown; none are claimed.

Formats

• HTML: https://ample.computer/recipes/asset-library/rails/data-exports
• Markdown: https://ample.computer/recipes/asset-library/rails/data-exports.md
• JSON: https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Aasset-library%3Arails%3Adata-exports

Next Actions

1. Browse the Catalog Index

   • Method: GET
   • Path: /v1/catalog

2. Search Published Recipes

   • Method: POST
   • Path: /v1/catalog/search
   • Body: {"limit":5,"query":"Host asset library with Rails: data exports"}

3. Prepare a Side-effect-free Deployment Plan

   • Method: POST
   • Path: /v1/catalog/plan
   • Body: {"inputs":{},"projectId":"","recipeId":"page:recipes:asset-library:rails:data-exports","recipeRevision":"r1"}

4. Read the Existing Agent Authentication Setup

   • Method: GET
   • Path: /mcp/setup

5. Browse Asset Library

   • Method: GET
   • Path: /v1/catalog/nodes/workload%3Aasset-library

6. Browse Rails

   • Method: GET
   • Path: /v1/catalog/nodes/stack%3Aframework-rails

7. Browse Generated Downloads

   • Method: GET
   • Path: /v1/catalog/nodes/pattern%3Agenerated-downloads

8. Browse Deploy Web App

   • Method: GET
   • Path: /v1/catalog/nodes/intent%3Adeploy-web-app