Implementing SQL version of the receipts interface

Signed-off-by: Ethan Wellenreiter <ewellenreiter@gmail.com>

backend/internal/storage/sql-receipts.go

@@ -0,0 +1,66 @@
+package storage
+
+import (
+	"context"
+	"database/sql"
+)
+
+type SQLReceiptsStore struct {
+	db *sql.DB
+}
+
+func (s *SQLReceiptsStore) GetByID(ctx context.Context, id int64) (*Receipt, error) {
+	query := `SELECT id, groupid, data FROM receipts WHERE id = $1`
+
+	receipt := &Receipt{}
+	err := s.db.QueryRowContext(ctx, query, id).Scan(&receipt.ID, &receipt.OwnerID, &receipt.Data)
+	if err != nil {
+		return nil, err
+	}
+
+	return receipt, nil
+}
+
+func (s *SQLReceiptsStore) Create(ctx context.Context, receipt *Receipt) error {
+	query := `
+				INSERT INTO receipts (groupid, data) 
+				VALUES ($1, $2) RETURNING id, created_at, updated_at`
+
+	ctx, cancel := context.WithTimeout(ctx, QueryTimeoutDuration)
+	defer cancel()
+
+	err := s.db.QueryRowContext(
+		ctx,
+		query,
+		receipt.OwnerID,
+		receipt.Data, // might need to marshal or serialize this
+	).Scan(
+		&receipt.ID,
+		&receipt.CreatedAt,
+		&receipt.UpdatedAt,
+	)
+	return err
+}
+
+func (s *SQLReceiptsStore) Delete(ctx context.Context, id int64) error {
+	query := `DELETE FROM receipts WHERE id = $1`
+
+	ctx, cancel := context.WithTimeout(ctx, QueryTimeoutDuration)
+	defer cancel()
+
+	res, err := s.db.ExecContext(ctx, query, id)
+	if err != nil {
+		return err
+	}
+
+	rows, err := res.RowsAffected()
+	if err != nil {
+		return err
+	}
+
+	if rows == 0 {
+		return ErrNotFound
+	}
+
+	return nil
+}