page:recipes:public directory:phoenix:public site

Host Public Directory with Phoenix: Public-Site Delivery

Summary

Deploy a public directory built with Phoenix on Ample using the public web service pattern. Compute runs the app in an isolated microVM behind a public HTTPS URL, and a published bucket serves public assets from the CDN host. Verified on Phoenix: a versioned, immutable-cached asset uploaded to a published bucket and served from the CDN URL alongside the app's own public HTTPS URL.

Representative Queries

• Host public directory with Phoenix: public-site delivery
• Where can I host Public directory built with Phoenix?
• I need an explicit origin-to-CDN delivery path and a tested public content build.

Resource Requirements

• Compute
• CDN

Infrastructure Requirements

• Compute: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; priced VM sizes.
• 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 Phoenix project that builds and starts with the documented commands (mix deps.get, MIX_ENV=prod mix compile and mix release in the builder, then the release bin script with PHX_SERVER=true on the elixir-1.18 template; PORT, DATABASE_URL and SECRET_KEY_BASE read in config/runtime.exs)
• A bucket from ample bucket create with its credentials passed as encrypted S3_* environment variables
• An Ample account token with servers:write, buckets:read

Tested Configuration

• Template: elixir-1.18
• Runtime: elixir
• Size: s-1vcpu-1gb
• Install: mix local.hex --force && mix local.rebar --force && MIX_ENV=prod mix deps.get --only prod
• Build: MIX_ENV=prod mix compile && MIX_ENV=prod mix release --overwrite
• Start: PHX_SERVER=true _build/prod/rel/$(ls _build/prod/rel | head -n 1)/bin/$(ls _build/prod/rel | head -n 1) start

Workflow Steps

1. Build and Start: mix deps.get, MIX_ENV=prod mix compile and mix release in the builder, then the release bin script with PHX_SERVER=true on the elixir-1.18 template; PORT, DATABASE_URL and SECRET_KEY_BASE read in config/runtime.exs. The server must bind 0.0.0.0 on PORT.
2. 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 Keep private data in an unpublished bucket.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.
3. 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=... --env CDN_PUBLIC_URL=...
4. Verify: Fetch the live URL and the pattern self-test route(s) (/p/versioned-static-assets) from the example; then run your own checks. On failure read ample logs --kind build then --kind runtime.
   Command: ample logs --kind build

Examples

• Phoenix Pattern Fixture: Multi-pattern Phoenix app whose public web service module was checked live; the module is under tests/deploy-canaries/_pattern-modules.

Success Checks

• App responds on its public URL: HTTP GET on / expects ample canary phoenix patterns.
• Versioned-static-assets self-test: HTTP GET on /p/versioned-static-assets expects a CDN URL whose content is served publicly.

Limitations

• Verified on the elixir-1.18 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Phoenix major versions are not verified.
• The public directory itself (your site content and build) is application code and was not separately tested.

Cost Estimate

• Monthly Amount: 5.0 USD
• Note: Always-on monthly price of the tested sizes; apps and databases auto-pause when idle.

Evidence Summary

• Canary Run: Phoenix pattern fixture deployed on Ample; checks passed for versioned-static-assets.

Next Actions

• Browse the catalog index
• Search published recipes by intent, stack and constraints
• Prepare a side-effect-free deployment plan for an authorized project
• Read the existing agent authentication setup
• Browse Public directory
• Browse Phoenix
• Browse Public web service
• Browse Deploy web app