• Backend for Frontend pattern - Challenges and Pitfalls - Exams of ASP.NET - Managing the shopping cart - Revisiting the CQRS pattern

    Challenges and Pitfalls – Modular Monolith

    September 11, 2024 - By 

    It is a misconception that monoliths are only suitable for small projects or small teams. A well-built monolith can go a long way, which is what a modular structure and a good analysis bring. Modular Monoliths can be very powerful and work well for different sizes of projects. It is essential to consider the pros and cons of each approach when selecting the application pattern for a project. Maybe a cloud-native, serverless, microservices application is what your next project needs, but perhaps a well-designed Modular Monolith would achieve the same performance at a tremendously lower cost.To help you make those…

  • Challenges and Pitfalls - Exams of ASP.NET - Managing the shopping cart - Revisiting the CQRS pattern - The message broker

    Sending HTTP requests to the API – Modular Monolith

    July 5, 2024 - By 

    Now that we have a working modular monolith, we can reuse similar HTTP requests than the previous versions.At the root of the REPR.API project, we can use the following: A new outcome in this API compared to the previous versions is when we try to add a product that does not exist in the catalog to our basket, like the following request: POST https://localhost:7164/basketsContent-Type: application/json{    “customerId”: 1,    “productId”: 5,    “quantity”: 99} Since the product 5 does not exist, the API returns the following: HTTP/1.1 400 Bad RequestContent-Type: application/problem+json{  “type”: “https://tools.ietf.org/html/rfc9110#section-15.5.1”,  “title”: “One or more validation errors occurred.”,  “status”: 400,  “errors”:…

  • ASP.NET Certifications - Backend for Frontend pattern - Challenges and Pitfalls - Exams of ASP.NET - The message broker - What is a Modular Monolith?

    The message broker – Modular Monolith

    January 16, 2024 - By 

    To handle the integration events between the catalog and the basket modules, I decided to pick MassTransit. To quote their GitHub project: MassTransit is a free, open-source distributed application framework for .NET. MassTransit makes it easy to create applications and services that leverage message-based, loosely-coupled asynchronous communication for higher availability, reliability, and scalability. I picked MassTransit because it is a popular project with 5,800 GitHub stars as of 2023 and supports many providers, including in-memory. Moreover, it offers many features that are way above our needs. Once again, we could have used anything. For example, MediatR could have also done…

  • ASP.NET Certifications - Backend for Frontend pattern - Challenges and Pitfalls - Exams of ASP.NET - What is a Modular Monolith?

    The URI space – Modular Monolith

    December 26, 2023 - By 

    The modules of this application follow the previously discussed URI space: /{module name}/{module space}. Each module has a Constants file at its root that looks like this: namespace REPR.Baskets;public sealed class Constants{    public const string ModuleName = nameof(Baskets);} We use the ModuleName constant in the {module name}ModuleExtensions files to set the URI prefix and tag the endpoints like this: namespace REPR.Baskets;public static class BasketModuleExtensions{    public static IEndpointRouteBuilder MapBasketModule(this IEndpointRouteBuilder endpoints)    {        _ = endpoints            .MapGroup(Constants.ModuleName.ToLower())            .WithTags(Constants.ModuleName)            .AddFluentValidationFilter()            // Map endpoints            .MapFetchItems()            .MapAddItem()            .MapUpdateQuantity()            .MapRemoveItem()        ;        return endpoints;    }} With this in place, both modules self-register themselves in the correct URI…

  • Challenges and Pitfalls - Exams of ASP.NET - The message broker - What is a Modular Monolith?

    Identifying the modules – Modular Monolith

    November 25, 2023 - By 

    Now that we have identified the entities, it is time to map them into modules. Let’s start with the following diagram:  Figure 20.4: Modules (bounded context) separation and entities relationships.   As expected, we have a product catalog, a shopping basket, and a customer management modules. What’s new here is the relationships between the entities. The catalog mainly manages the Product entity, yet the shopping basket needs to know about it to operate. The same logic applies to the Customer entity. In this case, the shopping basket only needs to know the unique identifier of each entity, but another module…

  • ASP.NET Certifications - Backend for Frontend pattern - Challenges and Pitfalls - Exams of ASP.NET

    Key Components of a Modular Monolith – Modular Monolith

    August 6, 2023 - By 

    The first thing to know about Modular Monoliths is that they are composed of different parts called modules. Each module is like a mini-app that performs a specific job. This job is related to a particular business capability. A business capability comes from the business domain and aims at a cohesive group of scenarios. Such a group is called a bounded context in DDD. Think of each module as a microservice or a well-defined chunk of the domain.That separation means everything we need to complete a specific task is in one module, which makes it easier for us to understand…

  • Backend for Frontend pattern - Challenges and Pitfalls - Exams of ASP.NET - Managing the shopping cart

    What are traditional Monoliths? – Modular Monolith

    July 5, 2023 - By 

    In a traditional monolithic architecture, we build the application as a single, indivisible unit. This leads to the functionalities being tightly coupled together, making it difficult to make changes or scale specific features. This approach makes creating a big ball of mud easier, particularly when the team invests little effort in domain modeling and analysis before and during development.On top of that, while this approach is simple and straightforward, it lacks the flexibility and scalability of more modern architectures. A monolith does not have to be indivisible, yet most end up this way because it is easy to create tight…

  • Challenges and Pitfalls - Exams of ASP.NET - Managing the shopping cart - Revisiting the CQRS pattern

    What is a Modular Monolith? – Modular Monolith

    April 15, 2023 - By 

    Before you begin: Join our book community on Discord Give your feedback straight to the author himself and chat to other early readers on our Discord server (find the “architecting-aspnet-core-apps-3e” channel under EARLY ACCESS SUBSCRIPTION). https://packt.link/EarlyAccess In the ever-evolving software development landscape, choosing the right architecture is like laying the foundation for a building. The architecture dictates how the software is structured, impacting its scalability, maintainability, and overall success. Traditional monolithic architecture and microservices have long been the dominant paradigms, each with advantages and challenges.However, a new architectural style has been gaining traction—Modular Monoliths. This approach aims to offer the…

  • ASP.NET Certifications - Backend for Frontend pattern - Challenges and Pitfalls - Exams of ASP.NET - What is a Modular Monolith?

    Decommissioning a legacy application – Introduction to Microservices Architecture-1

    September 21, 2022 - By 

    In this scenario, we have a legacy application to decommission and a microservices system to which we want to connect some existing capabilities. To achieve this, we can create one or more adapters to migrate all features and dependencies to the new model.Here is a representation of the current state of our system:  Figure 19.37: The original legacy application and its dependencies  The preceding diagram shows the two distinct systems, including the legacy application we want to decommission. Two other applications, dependency A and B, directly depend on the legacy application. The exact migration flow is strongly dependent on your…

  • Challenges and Pitfalls - Exams of ASP.NET - Managing the shopping cart - What is a Modular Monolith?

    Advantages and potential risks – Introduction to Microservices Architecture

    July 5, 2022 - By 

    This section explores some advantages and risks of separating a data store’s read and write operations using the CQRS pattern. Benefits of the CQRS pattern Potential Risks of using the CQRS pattern Conclusion CQRS helps divide queries and commands and helps encapsulate and isolate each block of logic independently. Mixing that concept with serverless computing or microservices architecture allows us to scale reads and writes independently. We can also use different databases, empowering us with the tools we need for the transfer rate required by each part of that system (for example, frequent writes and occasional reads or vice versa).Major…