relational catalog.md
Host product catalog with Spring Boot: relational catalog data
Summary
Deploy a product catalog built with Spring Boot on Ample using the transactional workflows 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. Verified on Spring Boot: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected). Not separately tested: your domain records, validation rules and concurrency policy; treat the product catalog-specific behavior as your application code.
Infrastructure requirements
- Verified: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.
- Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.
Prerequisites
- A Spring Boot project that builds and starts with the documented commands (./mvnw -q -DskipTests package (or the Gradle wrapper) producing one application jar, then java -jar on the jvm-21 template).
- A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env).
- An Ample account token with servers:write, databases:read.
Exact tested configuration
- template:
jvm-21 - runtime:
java - size:
s-1vcpu-2gb - build:
./mvnw -q -DskipTests package - start:
java -jar $(ls target/*.jar | grep -v -- '-plain' | head -n 1)
Steps
- Build and start. Run
./mvnw -q -DskipTests package(or the Gradle wrapper) producing one application jar, thenjava -jaron the jvm-21 template with server.port read from PORT. The server must bind 0.0.0.0 on PORT. - Implement the pattern on PostgreSQL. The fixture's module implements transactional workflows: an optimistic version check and an event row written in the same transaction. Copy the approach into your schema; keep migrations idempotent and run them with --release-command.
- Deploy. Run the synchronous deploy once and read the result (exit 0 live, 1 failed, 2 blocked).
ample deploy . --name <app-name> --public
- Verify. Fetch the live URL and the pattern self-test routes. Run your own checks. On failure read
ample logs <deployment_id> --kind buildthen--kind runtime.
ample logs <deployment_id> --kind build
Success checks
- App responds on its public URL, expect ample canary spring boot patterns.
- Transactional-workflows self-test.
Limitations
- Verified on the jvm-21 template at s-1vcpu-2gb with the example fixture; other sizes and Spring Boot major versions are not verified.
- The product catalog-specific behavior is application code and was not separately tested.
Cost estimate
Estimated 10.00 USD per month.
- App server x1
s-1vcpu-1gb: 5.00 USD - Managed PostgreSQL database x1
s-1vcpu-1gb: 5.00 USD
Verification evidence
- Various deployment checks and outcomes are logged for reference.