create a few initial E2E tests

src/services/db/price.db.ts

@@ -0,0 +1,53 @@
+// src/services/db/price.db.ts
+import type { Logger } from 'pino';
+import type { PriceHistoryData } from '../../types';
+import { getPool } from './connection.db';
+
+/**
+ * Repository for fetching price-related data.
+ */
+export const priceRepo = {
+  /**
+   * Fetches the historical price data for a given list of master item IDs.
+   * It retrieves the price in cents and the start date of the flyer for each item.
+   *
+   * @param masterItemIds An array of master grocery item IDs.
+   * @param logger The pino logger instance.
+   * @param limit The maximum number of records to return.
+   * @param offset The number of records to skip.
+   * @returns A promise that resolves to an array of price history data points.
+   */
+  async getPriceHistory(
+    masterItemIds: number[],
+    logger: Logger,
+    limit: number = 1000,
+    offset: number = 0,
+  ): Promise<PriceHistoryData[]> {
+    if (masterItemIds.length === 0) {
+      return [];
+    }
+
+    const query = `
+      SELECT
+        fi.master_item_id,
+        fi.price_in_cents,
+        f.valid_from AS date
+      FROM public.flyer_items fi
+      JOIN public.flyers f ON fi.flyer_id = f.flyer_id
+      WHERE
+        fi.master_item_id = ANY($1::int[])
+        AND f.valid_from IS NOT NULL
+        AND fi.price_in_cents IS NOT NULL
+      ORDER BY
+        fi.master_item_id, f.valid_from ASC
+      LIMIT $2 OFFSET $3;
+    `;
+
+    const result = await getPool().query(query, [masterItemIds, limit, offset]);
+    logger.debug(
+      { count: result.rows.length, itemIds: masterItemIds.length, limit, offset },
+      'Fetched price history from database.',
+    );
+    return result.rows;
+  },
+};