pamietnik/CLAUDE.md

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

Pamietnik (Codename: RALPH) is a life/travel journal consisting of three components:

• app/ — Android app (Kotlin + Jetpack Compose)
• backend/ — Go REST API + server-side rendered Web UI
• README.md — single source of truth for architecture, requirements, and backlog

Backend (backend/)

Stack: Go, chi router, pgx/v5 (PostgreSQL), golang-migrate, Argon2id

Run locally:

cd backend
docker-compose up -d          # starts PostgreSQL + API on :8080
./start.sh                    # alternative start script

Run only PostgreSQL and server manually:

docker-compose up -d postgres
go run ./cmd/migrate           # run DB migrations
go run ./cmd/server            # starts API on :8080 (default)

Env vars (with defaults):

• DATABASE_URL — postgres://ralph:ralph@localhost:5432/ralph?sslmode=disable
• LISTEN_ADDR — :8080
• UPLOAD_DIR — ./uploads

Tests:

go test ./...                  # all tests
go test ./internal/api/...     # handler tests only

Create a user:

go run ./cmd/createuser

DB migrations live in migrations/ and are applied via cmd/migrate.

Backend Architecture

cmd/
  server/     entry point: wires stores → router → http.Server
  migrate/    runs golang-migrate against DATABASE_URL
  createuser/ CLI to create users with Argon2id-hashed passwords
internal/
  domain/     shared model types (Trackpoint, Stop, Suggestion, …)
  db/         pgx store implementations (trackpoints, stops, suggestions, journal)
  auth/       session store (Postgres-backed), Argon2id hashing
  api/
    router.go     chi router wiring + middleware
    middleware.go session auth middleware
    ingest.go     POST /v1/trackpoints, POST /v1/trackpoints:batch
    query.go      GET /v1/days, /v1/trackpoints, /v1/stops, /v1/suggestions
    webui.go      server-side rendered web UI (login, /days, /days/{date})
    journal.go    journal entry endpoints
    response.go   shared response helpers

Key invariants:

• Idempotency via unique (device_id, event_id) — duplicate inserts return 200 OK
• Geocoding is event-driven (per Stop only), never bulk/periodic
• Sessions are stored in PostgreSQL (invalidatable on logout)
• OpenAPI spec must be kept current (openapi.yaml); changes only via PR + CI validation

Android App (app/)

Stack: Kotlin, Jetpack Compose, Room (SQLite), WorkManager, MapLibre

Build:

cd app
./gradlew assembleDebug
./gradlew installDebug        # install on connected device/emulator

Tests:

./gradlew test                           # JVM unit tests
./gradlew connectedAndroidTest           # instrumentation tests (device required)
./gradlew :app:testDebugUnitTest         # single module unit tests

Android Architecture

de.jacek.reisejournal/
  domain/       Trackpoint domain model
  data/         Room entities, DAOs, local DB
  service/      Background location foreground service
  worker/       WorkManager upload worker
  ui/
    home/       HomeScreen (Compose) + HomeViewModel
    navigation/ NavGraph
    theme/      Compose theme

Key invariants:

• Offline-first: every point persisted to Room before any upload attempt
• All points carry a client-generated event_id (UUID) for server-side idempotency
• source field distinguishes "gps" vs "manual" trackpoints
• Upload worker uses NetworkConnected constraint + retry/backoff
• No DB or network access directly in Composables — always via ViewModel

Project Decisions (from README)

Decision	Choice
Android UI	Jetpack Compose
Local DB	Room / SQLite
Backend DB	PostgreSQL
Maps	MapLibre + OpenStreetMap tiles (configurable source)
Geocoding	Nominatim (OSM), cached, provider-swappable via config
Auth (Web UI)	Session Cookie (Postgres-backed)
Password hashing	Argon2id
API spec	OpenAPI 3.1 (openapi.yaml)

Open Decisions (TBD)

• timestamp format: epochMillis vs RFC3339
• Android upload auth: X-API-Key vs Bearer/JWT
• HTTP payload: JSON vs Protobuf
• Batch limits (max items / max bytes)
• Retention policy for trackpoints
• Stop detection parameters (min duration, radius)
• Geocoding provider: Nominatim public vs self-hosted vs alternative