setup: databaseskjema og tilkoblingspool for PostgreSQL (#7)

backend/.env.example

@@ -1,3 +1,3 @@
 PORT=3001
-DATABASE_URL=postgres://brukernavn:passord@localhost:5432/handlelappen
+DATABASE_URL=postgres://localhost:5432/handlelapp
 KASSALAPP_API_KEY=

backend/db/migrations/001_init.sql

@@ -0,0 +1,73 @@
+-- Databaseskjema for Handlelappen (issue #7)
+-- Kjør fra backend/: psql handlelapp -f db/migrations/001_init.sql
+-- Kan kjøres flere ganger uten feil (IF NOT EXISTS).
+
+CREATE EXTENSION IF NOT EXISTS pg_trgm;
+
+-- Kategoritre fra Kassalapp (/categories). parent_id er NULL for toppnivå.
+CREATE TABLE IF NOT EXISTS categories (
+  id        INTEGER PRIMARY KEY,
+  parent_id INTEGER REFERENCES categories (id),
+  name      TEXT NOT NULL
+);
+
+-- Én rad per vare (EAN). Samme vare i flere kjeder deler rad.
+-- category_id er NULL for varer uten kategori («Ukategorisert»).
+CREATE TABLE IF NOT EXISTS products (
+  ean          TEXT PRIMARY KEY,
+  name         TEXT NOT NULL,
+  brand        TEXT,
+  vendor       TEXT,
+  image_url    TEXT,
+  description  TEXT,
+  ingredients  TEXT,
+  weight       NUMERIC,
+  weight_unit  TEXT,
+  nutrition    JSONB,
+  allergens    JSONB,
+  labels       TEXT[] NOT NULL DEFAULT '{}',  -- f.eks. {debio,nyt_norge}
+  category_id  INTEGER REFERENCES categories (id)
+);
+
+-- Én rad per vare per kjede.
+CREATE TABLE IF NOT EXISTS prices (
+  ean         TEXT NOT NULL REFERENCES products (ean) ON DELETE CASCADE,
+  store_code  TEXT NOT NULL,              -- f.eks. KIWI, MENY_NO
+  price       NUMERIC(10, 2) NOT NULL,
+  unit_price  NUMERIC(10, 2),
+  url         TEXT,
+  updated_at  TIMESTAMPTZ,
+  PRIMARY KEY (ean, store_code)
+);
+
+-- Brukergenererte data. owner_id er den anonyme bruker-ID-en fra nettleseren.
+CREATE TABLE IF NOT EXISTS shopping_lists (
+  id            SERIAL PRIMARY KEY,
+  owner_id      TEXT NOT NULL,
+  name          TEXT NOT NULL,
+  status        TEXT NOT NULL DEFAULT 'ACTIVE' CHECK (status IN ('ACTIVE', 'DONE')),
+  in_use        BOOLEAN NOT NULL DEFAULT false,
+  created_at    TIMESTAMPTZ NOT NULL DEFAULT now(),
+  updated_at    TIMESTAMPTZ NOT NULL DEFAULT now(),
+  completed_at  TIMESTAMPTZ
+);
+
+CREATE TABLE IF NOT EXISTS list_items (
+  id        SERIAL PRIMARY KEY,
+  list_id   INTEGER NOT NULL REFERENCES shopping_lists (id) ON DELETE CASCADE,
+  ean       TEXT NOT NULL REFERENCES products (ean),
+  quantity  INTEGER NOT NULL DEFAULT 1 CHECK (quantity > 0),
+  note      TEXT,
+  checked   BOOLEAN NOT NULL DEFAULT false,
+  UNIQUE (list_id, ean)
+);
+
+-- Indekser for søk, sortering og filtrering
+CREATE INDEX IF NOT EXISTS products_name_trgm_idx ON products USING gin (name gin_trgm_ops);
+CREATE INDEX IF NOT EXISTS products_brand_idx     ON products (brand);
+CREATE INDEX IF NOT EXISTS products_category_idx  ON products (category_id);
+CREATE INDEX IF NOT EXISTS products_labels_idx    ON products USING gin (labels);
+CREATE INDEX IF NOT EXISTS prices_price_idx       ON prices (price);
+CREATE INDEX IF NOT EXISTS prices_store_idx       ON prices (store_code);
+CREATE INDEX IF NOT EXISTS shopping_lists_owner_idx ON shopping_lists (owner_id);
+CREATE INDEX IF NOT EXISTS list_items_list_idx    ON list_items (list_id);

backend/src/db.ts

@@ -0,0 +1,10 @@
+import 'dotenv/config';
+import pg from 'pg';
+
+const connectionString = process.env.DATABASE_URL;
+if (!connectionString) {
+  throw new Error('DATABASE_URL mangler i backend/.env (se .env.example)');
+}
+
+// Én felles tilkoblingspool for hele backenden.
+export const pool = new pg.Pool({ connectionString });