gushakov

import lombok.Getter;

import javax.transaction.Transactional;
import java.math.BigDecimal;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.time.Instant;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.util.Currency;

gushakov

Hi Alex,

Wow! What an impressive endeavor you've embarked on with your Bid Binding engine. It's really rare to have someone sharing complete design and development process with the public. Here are some of my thoughts...

Your domain is an intrinsically asynchronous and a parallelized domain. This naturally warrants an EDA approach. So I can understand the direction of your thought and the general enthusiasm for event-driven canvas of the overall design.

As you may have seen in some of my articles on Medium, several years ago I was quite into EDA and CQRS. Here and here are some of my projects leveraging Axon platform. I'm not at all familiar with AWS stack, but I can guess that AWS EventBridge plays the same role as Axon.

Not to discourage you by any means, but let me tell your that I've been somewhat disenchanted with EDA since. Here are some of my frustrations with this architecture.

gushakov

public class CleanController {

    // autowire an instance of a use case
    UsecaseInputPort useCase;

    // note the "void" of the request handler method
    public void handleRequest(RequestModel inputDto) {

        // execute the use case
        useCase.execute(inputDto);

gushakov

public class Controller {

    // autowire a presenter through constructor argument injection,
    // for example
    PresenterOutputPort presenter;

    // also autowire any output ports to any of the secondary adapters
    // needed to perform use case logic
    SecondaryAdapterOutputPort someOperations;

gushakov

@Transactional
@Override
public void assignRoute(String trackingId, RouteDto selectedRoute) {

	try {

		// RBAC check: user must at least have Agent role
		securityOps.assertThatUserIsAgent();

		// make sure we retrieved candidate route from the session successfully

gushakov

public interface SecurityOutputPort {

    // Roles for the Cargo tracking application users
    String ROLE_CARGO_AGENT = "CARGO_AGENT";
    String ROLE_CARGO_MANAGER = "CARGO_MANGER";

    // Special region used for routing permission check
    Region SPECIAL_REGION = Europe;

    // this is the only method which needs to be implemented in

gushakov

@Bean
public SecurityFilterChain webSecurityFilterChain(HttpSecurity http) throws Exception {

	// no RBAC configuration here: all security is in use cases

	http.authorizeRequests()
			.anyRequest()
			.permitAll()
			.and()
			.formLogin()

gushakov

@Bean
public UserDetailsService inMemoryUserDetailsService() {

	InMemoryUserDetailsManager userDetailsManager = new InMemoryUserDetailsManager();

	userDetailsManager.createUser(
			User.withDefaultPasswordEncoder()
					.username("agent")
					.password("test")
					.authorities(ROLE_CARGO_AGENT)

gushakov

private Delivery(HandlingEvent lastEvent, Itinerary itinerary, RouteSpecification routeSpecification) {
        this.lastEvent = lastEvent;
        this.misdirected = calculateMisdirectionStatus(itinerary);
        this.routingStatus = notNull(calculateRoutingStatus(itinerary, routeSpecification));
        this.transportStatus = notNull(calculateTransportStatus());
        this.lastKnownLocation = calculateLastKnownLocation().orElse(null);
        this.currentVoyage = calculateCurrentVoyage().orElse(null);
        this.eta = calculateEta(itinerary);
        this.nextExpectedActivity = calculateNextExpectedActivity(routeSpecification, itinerary);
    }

gushakov

    @Builder
    public Delivery(TransportStatus transportStatus, UnLocode lastKnownLocation, VoyageNumber currentVoyage,
                    UtcDateTime eta, RoutingStatus routingStatus, boolean misdirected,
                    HandlingActivity nextExpectedActivity) {
        this.transportStatus = notNull(transportStatus);
        this.lastKnownLocation = lastKnownLocation;
        this.currentVoyage = currentVoyage;
        this.lastEvent = null;
        this.eta = eta;
        this.routingStatus = notNull(routingStatus);