Architecture and Principles Flashcards
What is Dapper?
Dapper is a lightweight and high-performance Object-Relational Mapping (ORM) library for .NET applications, allowing efficient database access using simple SQL queries.
How does Dapper differ from other ORMs?
Dapper focuses on simplicity and performance by mapping database query results directly to objects without much overhead.
Is Dapper suitable for complex data models?
Yes, Dapper can handle complex data models effectively by using multi-mapping and query composition techniques.
Can Dapper handle stored procedures?
Yes, Dapper can work with stored procedures by using the Query, QueryMultiple, and Execute methods.
Does Dapper support async operations?
Yes, Dapper provides asynchronous methods for executing queries and commands, which can enhance application responsiveness.
In which scenarios is Dapper most beneficial?
Dapper shines in scenarios where you need high-performance data access, like read-heavy applications or reporting systems.
How can parameterized queries be executed using Dapper?
Dapper supports parameterized queries by passing an anonymous type or a strongly-typed object to the query methods.
What’s the role of Dapper’s SqlMapper class?
SqlMapper is the core class in Dapper that provides extension methods for database operations and query mapping.
Is Dapper open-source?
Yes, Dapper is an open-source project maintained by the Stack Exchange team.
Can Dapper be used with non-relational databases?
While Dapper is primarily designed for relational databases, it might work with non-relational databases, but its design is better suited for SQL-based systems.
What is Clean Architecture?
Clean Architecture is a software design principle that emphasizes separation of concerns and the independence of business logic from external frameworks and tools.
What are the core components of Clean Architecture?
Clean Architecture consists of layers such as Entities, Use Cases, Interface Adapters, and Frameworks & Drivers.
Why is Dependency Inversion Principle important in Clean Architecture?
Dependency Inversion Principle promotes decoupling and modularity by allowing high-level modules to depend on abstractions, not concrete implementations
How does Clean Architecture improve maintainability?
Clean Architecture enforces a clear separation between business rules and external dependencies, making it easier to modify or replace specific components without affecting others.
What is the purpose of the “Entities” layer in Clean Architecture?
The Entities layer holds business entities, enterprise-wide business rules, and application-specific logic.
Explain the role of the “Use Cases” layer.
The Use Cases layer contains application-specific use cases and business logic, representing the application’s core functionality.
What are “Interface Adapters” in Clean Architecture?
Interface Adapters convert data between the use cases and the external world, including controllers, presenters, and gateways.
How does Clean Architecture facilitate automated testing?
Clean Architecture’s separation of concerns allows you to test each layer in isolation, enabling thorough unit and integration testing.
Is Clean Architecture suitable for small projects?
Clean Architecture’s benefits become more apparent in larger projects, but its principles can be scaled down for smaller applications as well.
Can Clean Architecture be applied to any programming language?
Yes, Clean Architecture’s principles can be adapted to various programming languages and technologies.
What is Hexagonal Architecture (a.k.a. Ports and Adapters)?
Hexagonal Architecture is a design pattern that focuses on creating a flexible and maintainable system by isolating core business logic from external dependencies.
Why is it called “Hexagonal” Architecture?
The architecture is named after the shape of the diagram, where the core application logic is in the center, surrounded by “ports” and “adapters.”
What are the “ports” in Hexagonal Architecture?
Ports are interfaces that define the interaction points between the application and the external world, such as input and output operations.
What are “adapters” in this context?
Adapters are implementations of the ports, responsible for translating external requests into calls to the core application and vice versa.
How does Hexagonal Architecture improve testability?
By decoupling the core logic from external dependencies, testing becomes easier as you can mock or replace adapters during testing.
Can Hexagonal Architecture be applied to monolithic applications only?
No, Hexagonal Architecture principles can be applied to both monolithic and microservices architectures to achieve modularity.
Does Hexagonal Architecture add complexity to development?
While there’s an initial overhead in setting up the architecture, it often reduces complexity in the long run by making the system more maintainable and adaptable.
Is Hexagonal Architecture suitable for every project?
Hexagonal Architecture is particularly beneficial for complex applications, where maintaining separation between core logic and external concerns is crucial.
How does Hexagonal Architecture aid in technology changes?
The core logic remains unchanged when adapting to new technologies, as only the adapters need to be adjusted to work with new frameworks or tools.
Are there any real-world examples of projects using Hexagonal Architecture?
Yes, projects like CQRS-based systems, domain-driven design implementations, and microservices architectures often adopt Hexagonal Architecture principles.
What are microservices?
Microservices is an architectural approach where an application is composed of loosely coupled, independently deployable services that communicate over a network.
What’s the key benefit of microservices?
Microservices enable scalability, maintainability, and agility by breaking down an application into smaller, manageable services.
How do microservices communicate with each other?
Microservices often use lightweight communication mechanisms like HTTP/REST, message queues, or event-driven architectures.
What challenges can arise in microservices around data consistency?
Maintaining data consistency across distributed services can be challenging; solutions include event sourcing, distributed transactions, and eventual consistency.
What’s the difference between monolithic and microservices architectures?
Monolithic architectures have all components within a single codebase, while microservices split functionalities into separate services.
Can microservices be built using different programming languages?
Yes, microservices can be built using various programming languages and technologies, as long as the services can communicate effectively.
How does microservices architecture impact deployment and scaling?
Microservices can be deployed and scaled independently, allowing for more efficient resource allocation and better responsiveness.
What is the role of API gateways in microservices?
API gateways handle routing, authentication, load balancing, and sometimes aggregation of requests for various microservices.
What are the challenges of testing in microservices?
Testing can become complex due to the distributed nature of microservices; strategies like contract testing and service virtualization can help.
Is there a relationship between microservices and containerization?
Yes, containerization technologies like Docker are often used to package microservices along with their dependencies for consistency in different environments.
What is Domain-Driven Design (DDD)?
Domain-Driven Design is a software design approach that focuses on aligning software models with the real-world domain, enhancing collaboration between technical and domain experts
Why is domain knowledge crucial in DDD?
Domain knowledge helps in creating a shared understanding between developers and domain experts, leading to more accurate and effective software models.
What is the core concept of a “domain model” in DDD?
A domain model represents the core business logic and rules of an application, capturing essential concepts, behaviors, and relationships.
How does DDD handle complex business rules?
DDD provides techniques like aggregates, value objects, and entities to encapsulate and manage complex business rules within the domain model.
What is an “aggregate” in DDD?
An aggregate is a cluster of domain objects treated as a single unit for data changes, ensuring consistency and integrity.
What’s the difference between “entities” and “value objects” in DDD?
Entities have identity and are distinguishable, while value objects do not have identity and are immutable representations of concepts.
What are “repositories” in DDD?
Repositories provide an abstraction for accessing and managing aggregates, helping to maintain a clean separation between domain logic and data access.
How does DDD approach tackling ubiquitous language?
Ubiquitous language refers to using a common vocabulary between developers and domain experts; DDD encourages modeling software using this shared language.
What is the role of “bounded contexts” in DDD?
Bounded contexts define specific boundaries where a certain model is valid; they help avoid ambiguity when different models use the same terms differently.
Can DDD be used with any programming language or technology?
Yes, DDD’s principles can be applied to various programming languages and technologies, making it adaptable to different contexts.
What is CQRS (Command Query Responsibility Segregation)?
CQRS is a design pattern that separates read and write operations into distinct paths, optimizing the data model and processing for each operation.
What problem does CQRS address
CQRS helps solve scalability and performance challenges by allowing separate optimization of read-heavy and write-heavy parts of an application.
How does CQRS affect the data store?
CQRS often leads to different storage solutions for reads and writes, enabling each storage mechanism to be tailored to its specific usage.
What is a “command” in CQRS?
A command represents an intention to change the state of the system; it’s responsible for updating data and enforcing business rules.
What is a “query” in CQRS?
A query represents a request to retrieve data from the system; it’s focused on reading and displaying information without modifying the state.
Does adopting CQRS lead to eventual consistency?
Yes, CQRS can result in eventual consistency since writes and reads occur separately, potentially causing a delay in data synchronization.
Are there any challenges associated with CQRS implementation?
CQRS introduces complexity due to managing the divergence between read and write models, as well as maintaining synchronization.
Is CQRS suitable for every application?
CQRS is beneficial for applications with complex or varying read and write requirements, while simpler applications might not require its overhead.
Can CQRS be used in conjunction with other architectural patterns?
Yes, CQRS can be combined with other patterns like Event Sourcing and DDD to create a comprehensive solution for complex applications.
How does CQRS affect the user experience?
CQRS might lead to slightly different views of data for readers compared to writers, which could impact user expectations and understanding of the system’s behavior.
