Host inventory manager with Phoenix: CSV imports

Summary

Deploy a inventory manager built with Phoenix on Ample using the bulk import staging 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 Phoenix: a CSV staged as an object, row-level validation with per-row errors recorded, and a restart-safe import keyed by import id (imported=2 rejected=1 restart=ok). Not separately tested: your import format, mapping and conflict rules; treat the inventory manager-specific behavior as your application code.

Infrastructure requirements

• Compute: verified (Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.)
• Postgres: verified (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: verified (Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.)

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 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

Exact 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

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. Implement the pattern on PostgreSQL. The fixture's module implements bulk import staging: a CSV staged as an object, row-level validation with per-row errors recorded, and a restart-safe import keyed by import id (imported=2 rejected=1 restart=ok). 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 <app-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/bulk-import-staging) from the example; then run your own checks. On failure read ample logs <deployment_id> --kind build then --kind runtime.

   ample logs <deployment_id> --kind build
   

Tested examples

• Phoenix pattern fixture (tests/deploy-canaries/phoenix-patterns): Multi-pattern Phoenix app whose bulk import staging module was checked live; the module is under tests/deploy-canaries/_pattern-modules.

Success checks

• app responds on its public URL (/ on the live URL, expect ample canary phoenix patterns)
• bulk-import-staging self-test (/p/bulk-import-staging on the live URL, expect imported=2 rejected=1 restart=ok)

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 inventory manager itself (your import format, mapping and conflict 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.