What are microservices and what are their advantages and disadvantages?

Microservices are an architectural style where an application is built as a collection of small, independent services that communicate over network protocols. Each service is self-contained, focuses on a specific business capability, and can be deployed independently.

Advantages:

• Independent Deployment: Services can be deployed without affecting others
• Technology Flexibility: Each service can use different tech stacks
• Scalability: Scale individual services based on demand
• Fault Isolation: Failures in one service don't crash the entire system
• Team Autonomy: Small teams can own and develop services independently
• Faster Development: Parallel development across multiple teams

Disadvantages:

• Complexity: Distributed systems are inherently complex
• Network Latency: Inter-service communication overhead
• Data Consistency: Maintaining consistency across services is challenging
• Testing Difficulty: End-to-end testing becomes more complex
• Operational Overhead: More services to monitor, deploy, and maintain
• Distributed Transactions: Harder to implement ACID transactions

Example in .NET Core:

// Product Service
public class ProductService
{
    private readonly IHttpClientFactory _httpClientFactory;
    
    public async Task GetProductWithInventory(int productId)
    {
        var product = await _productRepository.GetByIdAsync(productId);
        
        // Call inventory microservice
        var client = _httpClientFactory.CreateClient("InventoryService");
        var inventory = await client.GetFromJsonAsync($"/api/inventory/{productId}");
        
        product.StockLevel = inventory.Quantity;
        return product;
    }
}