[golang] implement shipyards visits

golang/pkg/database/shipyards.go

@@ -0,0 +1,42 @@
+package database
+
+import (
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"git.adyxax.org/adyxax/spacetraders/golang/pkg/model"
+)
+
+func (db *DB) LoadShipyard(symbol string) (*model.Shipyard, error) {
+	var buf []byte
+	if err := db.QueryRow(`SELECT data FROM shipyards WHERE data->>'symbol' = ?;`, symbol).Scan(&buf); err != nil {
+		return nil, fmt.Errorf("failed to query shipyard: %w", err)
+	}
+	var shipyard model.Shipyard
+	if err := json.Unmarshal(buf, &shipyard); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal shipyard: %w", err)
+	}
+	return &shipyard, nil
+}
+
+func (db *DB) SaveShipyard(shipyard *model.Shipyard) error {
+	data, err := json.Marshal(shipyard)
+	if err != nil {
+		return fmt.Errorf("failed to marshal shipyard: %w", err)
+	}
+	_, err = db.Exec(
+		`INSERT INTO shipyards(data, updated)
+                VALUES (json(:data), :updated)
+         ON CONFLICT DO UPDATE SET data = :data, updated = :updated
+		                       WHERE data->>'symbol' = :symbol;`,
+		sql.Named("data", data),
+		sql.Named("symbol", shipyard.Symbol),
+		sql.Named("updated", time.Now()),
+	)
+	if err != nil {
+		return fmt.Errorf("failed to append shipyard: %w", err)
+	}
+	return nil
+}