sonus21

@require_GET
def order_detail(request, id):
    order = get_object_or_404(Order, id=id)
    return JsonResponse(model_to_dict(order), safe=False)


@require_POST
@csrf_exempt
def create_order(request):
    form = CreateOrder(json.loads(request.body))

sonus21

package database
const (
	Primary   = "primary"
	Secondary = "secondary"
)

sonus21

public class Constants {
    public static final String PRIMARY = "primary";
    public static final String SECONDARY = "secondary";
}

sonus21

@RequestMapping("/api/v1/orders")
@RestController
@Database(Constants.SECONDARY)
public class OrderController {
    private final OrderService orderService;

    public OrderController(OrderService orderService) {
        this.orderService = orderService;
    }

sonus21

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(basePackages = {"com.github.sonus21.readwrite.repositories"})
@EntityScan(basePackages = "com.github.sonus21.readwrite.models.entities")
public class SqlDatabaseConfiguration {

    private final DataSourceSecondaryConfig dataSourceSecondaryConfig;
    private final DataSourcePrimaryConfig dataSourcePrimaryConfig;

    @Autowired

sonus21

public class DatabaseRouter extends AbstractRoutingDataSource {
    @Override
    protected Object determineCurrentLookupKey() {
        return DatabaseContext.get();
    }
}

sonus21

public class DatabaseContext {
    private static final ThreadLocal<String> databaseName = new ThreadLocal<>();

    public static void set(String name) {
        databaseName.set(name);
    }

    public static void clear() {
        databaseName.remove();
    }

sonus21

@Aspect
@Component
public class DatabaseAspect {
    /**
     * AOP joint point handler that will be invoked by AOP when it encounters a method annotated with Database
     * or the class containing this method is annotated with Database.
     *
     * @param jointPoint joint point object
     * @return the result of joint point
     * @throws Throwable if any exception occurred while handling joint point

sonus21

/**
 * A Database annotation that should be used at controller,worker,consumer,methods or classes
 * to route the database traffic to appropriate node.
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.TYPE, ElementType.METHOD})
public @interface Database {
    String value() default "";
}

sonus21

func getPrimaryDbConfig() database.MySqlConfig {
	// use any other mechanism like viper/toml/env file to create the cpnfig
	return database.MySqlConfig{
		Host:                 "localhost",
		Port:                 3306,
		Database:             "my_app_db",
		Username:             "my_app",
		Password:             "my_app_pass",
		MaxConnectionRetries: 3,
		MaxOpenConnection:    30,