I Built a REST Microservice With a Database in 3 Files — and Wrote Zero Code

Описание и применение

Создан REST‑микросервис с SQLite, полностью описанный в трёх конфигурационных файлах HCL без кода приложения. Mycel автоматически генерирует сервер, маршрутизацию, валидацию, трансформацию и ретраи, а также эндпоинты health/metrics/debug.

Задача

Developers spend excessive time writing boilerplate plumbing for microservices, leading to repetitive code for routing, validation, database access, and error handling.

Результат

A production‑ready REST microservice running in two minutes, with CRUD endpoints, validation, data transformation, retries, and built‑in health/metrics/debug, all defined in three configuration files and requiring no application code.

Рабочий процесс

• 1. Create SQLite database schema via CLI
• 2. Write three HCL files: config.mycel, connectors/connectors.mycel, flows/flows.mycel
• 3. Define service name and version in config.mycel
• 4. Declare connectors for REST API and SQLite database
• 5. Define flows mapping API operations to database targets
• 6. (Optional) Add validation, transformation, and error handling blocks inside flows
• 7. Build or pull Mycel Docker image
• 8. Run Mycel container mounting config directory and exposing port

Доказательства

Mycel scans the config directory recursively, so the file layout is yours to choose — one file or fifty.

Источник

Now hit the API like any other REST service: ... A working CRUD microservice. Zero lines of Go, JavaScript, or anything else.

Источник