开源外卖系统多运力并存模型设计：自营+众包架构实现

CREATE TABLE delivery_provider (
    id BIGINT PRIMARY KEY AUTO_INCREMENT,
    provider_name VARCHAR(50),
    provider_type VARCHAR(20), -- SELF / CROWD / THIRD_PARTY
    status TINYINT DEFAULT 1,
    create_time DATETIME
);

CREATE TABLE rider (
    id BIGINT PRIMARY KEY AUTO_INCREMENT,
    name VARCHAR(50),
    phone VARCHAR(20),
    provider_id BIGINT,
    status VARCHAR(20), -- ONLINE / OFFLINE / BUSY
    latitude DECIMAL(10,6),
    longitude DECIMAL(10,6),
    FOREIGN KEY (provider_id) REFERENCES delivery_provider(id)
);

ALTER TABLE orders 
ADD COLUMN provider_id BIGINT,
ADD COLUMN dispatch_status VARCHAR(20);

public interface DispatchStrategy {
    Rider dispatch(Order order);
}

public class SelfDispatchStrategy implements DispatchStrategy {

    @Override
    public Rider dispatch(Order order) {
        List<Rider> riders = riderRepository.findAvailableRiders("SELF");

        return riders.stream()
                .min(Comparator.comparing(r -> distance(r, order)))
                .orElse(null);
    }

    private double distance(Rider rider, Order order) {
        return GeoUtil.calculateDistance(
                rider.getLatitude(),
                rider.getLongitude(),
                order.getLatitude(),
                order.getLongitude()
        );
    }
}

public class CrowdDispatchStrategy implements DispatchStrategy {

    @Override
    public Rider dispatch(Order order) {
        List<Rider> riders = riderRepository.findAvailableRiders("CROWD");

        return riders.stream()
                .min(Comparator.comparing(r -> distance(r, order)))
                .orElse(null);
    }

    private double distance(Rider rider, Order order) {
        return GeoUtil.calculateDistance(
                rider.getLatitude(),
                rider.getLongitude(),
                order.getLatitude(),
                order.getLongitude()
        );
    }
}

public class DispatchCenter {

    private DispatchStrategy selfStrategy;
    private DispatchStrategy crowdStrategy;

    public Rider dispatch(Order order) {

        Rider rider = selfStrategy.dispatch(order);

        if (rider != null) {
            order.setProviderId(1L); // SELF
            return rider;
        }

        rider = crowdStrategy.dispatch(order);

        if (rider != null) {
            order.setProviderId(2L); // CROWD
            return rider;
        }

        // 调用第三方接口
        return thirdPartyDispatch(order);
    }

    private Rider thirdPartyDispatch(Order order) {
        // 调用第三方API
        ThirdPartyResponse response = thirdPartyApi.createOrder(order);
        return convert(response);
    }
}

public BigDecimal calculateRiderIncome(Order order) {

    if (order.getProviderType().equals("SELF")) {
        return order.getDeliveryFee().multiply(new BigDecimal("0.8"));
    }

    if (order.getProviderType().equals("CROWD")) {
        return order.getDeliveryFee().multiply(new BigDecimal("0.9"));
    }

    if (order.getProviderType().equals("THIRD_PARTY")) {
        return order.getDeliveryFee().subtract(order.getThirdPartyCost());
    }

    return BigDecimal.ZERO;
}

String lockKey = "dispatch_lock:" + order.getId();
Boolean success = redisTemplate.opsForValue()
        .setIfAbsent(lockKey, "1", 10, TimeUnit.SECONDS);

if (!success) {
    throw new RuntimeException("正在派单中");
}