Cross-Service Integration

Communication Methods

Entity Event Bus (Automatic Sync)

// Producer (in source service) - Platform handles automatically
// Entities sync via PlatformCqrsEntityEventBusMessageProducer

// Consumer (in target service)
internal sealed class UpsertEmployeeOnEventConsumer :
    PlatformApplicationMessageBusConsumer<EmployeeEntityEventBusMessage>
{
    public override async Task<bool> HandleWhen(
        EmployeeEntityEventBusMessage msg, string routingKey) => true;

    public override async Task HandleLogicAsync(
        EmployeeEntityEventBusMessage msg, string routingKey)
    {
        // Wait for dependencies with timeout
        var companyExists = await Util.TaskRunner.TryWaitUntilAsync(
            () => companyRepo.AnyAsync(c => c.Id == msg.Payload.EntityData.CompanyId),
            maxWaitSeconds: 300);

        if (!companyExists) return;

        // CREATE/UPDATE
        if (msg.Payload.CrudAction == Created ||
            (msg.Payload.CrudAction == Updated && !msg.Payload.EntityData.IsDeleted))
        {
            var existing = await repository.FirstOrDefaultAsync(
                e => e.Id == msg.Payload.EntityData.Id);

            if (existing == null)
                await repository.CreateAsync(
                    msg.Payload.EntityData.ToEntity()
                        .With(e => e.LastMessageSyncDate = msg.CreatedUtcDate));
            else if (existing.LastMessageSyncDate <= msg.CreatedUtcDate)
                await repository.UpdateAsync(
                    msg.Payload.EntityData.UpdateEntity(existing)
                        .With(e => e.LastMessageSyncDate = msg.CreatedUtcDate));
        }

        // DELETE
        if (msg.Payload.CrudAction == Deleted ||
            (msg.Payload.CrudAction == Updated && msg.Payload.EntityData.IsDeleted))
            await repository.DeleteAsync(msg.Payload.EntityData.Id);
    }
}

Service Boundaries

Key Patterns

Message Naming Convention

Anti-Patterns

• Direct database access across services
• Synchronous HTTP calls between services
• Not waiting for dependencies before processing
• Ignoring LastMessageSyncDate (causes race conditions)
• Processing messages out of order