page:recipes:public directory:phoenix:public media

Host public directory with Phoenix: object-stored public media

Summary

Deploy a public directory built with Phoenix on Ample using the public media 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, and a published bucket serves public assets from the CDN host. Verified on Phoenix: an object written to a published bucket with an immutable Cache-Control header, a mapping row, and the CDN URL serving it publicly.

Representative Queries

• Host public directory with Phoenix: object-stored public media
• Where can I host Public directory built with Phoenix?
• I need an object layout, public asset URL policy and CDN delivery configuration.

Resource Requirements

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

Infrastructure Requirements

1. Compute: Apps run in isolated x86_64 Firecracker microVMs.
2. Postgres: Managed PostgreSQL 16 runs in its own microVM.
3. S3-compatible object storage: Buckets are S3-compatible with issued credentials.
4. CDN: The CDN host serves objects from published buckets.

Prerequisites

• A Phoenix project that builds and starts with the documented commands.
• A PostgreSQL driver reading DATABASE_URL at runtime.
• A bucket with its credentials passed as encrypted S3_* environment variables and a second, published bucket for public assets.
• An Ample account token with required permissions.

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: Run the commands specified to build and start the app.
2. Implement the pattern on PostgreSQL: Copy the public media library module and keep migrations idempotent.
3. Wire object storage: Create the bucket(s) and pass necessary values as --env.
4. Deploy: Run the synchronous deploy command and read the result.
5. Verify: Fetch the live URL and run checks on the deployed app.

Success Checks

• App responds on its public URL.
• Public-media-library self-test.

Limitations

• Verified only on the elixir-1.18 template at s-1vcpu-1gb.
• The public directory's behavior is application code.
• Other configuration, compliance, and performance metrics are unknown.

Cost Estimate

• Currency: USD
• Monthly Amount: 10.0
• Components:
  • App server: s-1vcpu-1gb
  • Managed PostgreSQL database: s-1vcpu-1gb

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.