Understanding RESTful Services and APIs

REST APIs

• REST is an architectural style for distributed systems
• REST uses HTTP methods (GET, POST, PUT, DELETE) to perform CRUD operations on resources
• Resources are typically represented in JSON or XML format

REST vs SOAP

• SOAP is an XML-based messaging protocol that is used to transfer data between distributed applications and systems
• SOAP follows a very strict structure
• REST is more popular than SOAP but SOAP is still used in many enterprise-scale systems that require advanced security and error handling features

ASP.NET MVC vs ASP.NET Web API

• ASP.NET MVC is used to create web applications that can return views as well as data
• ASP.NET Web API is used to create RESTful HTTP services which return only data and no view
• In MVC, the request is mapped to the actions name
• In Web API, the request is mapped to the actions based on HTTP verbs

HTTP Methods

• HTTP methods define the type of operation performed on a resource

###.NET RESTful Service Best Practices

• API Design:
  • Use a consistent naming convention for resources and endpoints
  • Use clear and concise documentation
• Security:
  • Implement authentication and authorization
  • Secure communication
  • Input validation
• Performance:
  • Optimize database queries
  • Implement caching
  • Monitor performance
• Documentation:
  • Provide comprehensive API documentation
  • Use a format like Swagger
• Error Handling:
  • Provide meaningful error messages
  • Implement error handling
• Testing:
  • Write unit tests for API functionality
  • Perform integration testing
• Versioning:
  • Use versioning to manage changes in the API
• Logging and Monitoring:
  • Log API requests and responses
  • Monitor API performance and errors
• Compliance:
  • Adhere to relevant compliance standards
• Scalability:
  • Design the API for scalability
  • Use a cloud platform for deployment

Status Codes

• 1xx Informational
  • Communicates transfer protocol-level information
• 2xx Success
  • Indicates that the client’s request was accepted successfully
• 3xx Redirection
  • Indicates that the client must take some additional action in order to complete their request
• 4xx Client Error
  • This category of error status codes points the finger at clients
• 5xx Server Error
  • The server takes responsibility for these error status codes
• Common Status Codes
  • 200 - OK
  • 201 - Created
  • 202 - Accepted
  • 204 - No Content
  • 301 - Moved Permanently
  • 302 - Found
  • 303 - See Other
  • 304 - Not Modified
  • 307 - Temporary Redirect
  • 400 - Bad Request
  • 401 - Unauthorized
  • 403 - Forbidden
  • 404 - Not Found
  • 405 - Method Not Allowed
  • 406 - Not Acceptable
  • 412 - Precondition Failed
  • 415 - Unsupported Media Type
  • 500 - Internal Server Error
  • 501 - Not Implemented
  • 502 - Bad Gateway

HTTP Headers

• Categories of HTTP Headers:
  • General Headers: Apply to both requests and responses but do not relate to the data in the body.
  • Request Headers: Provide additional information about the request.
  • Response Headers: Provide additional information about the response.
  • Entity Headers: Provide information about the body of the resource, such as its content length or MIME type.

CORS

• Cross-Origin Resource Sharing (CORS) is a security feature that prevents web pages from making requests to a different domain than the one that served the web page.
• CORS allows or restricts resources on a web page to be requested from another domain outside the domain from which the resource originated

Authentication and Authorization

• Authentication verifies the identity of a user or system
  • Common Authentication Methods: Basic Authentication, Token-Based Authentication (JWT), OAuth 2.0, and API Keys
• Authorization determines what an authenticated user is allowed to do
  • Common Authorization Strategies: Role-Based Access Control (RBAC), Attribute-Based Access Control (ABAC), and Access Control Lists (ACLs)

ApiController vs Controller

• ApiController class is used for building HTTP APIs
• Controller class is used for building web applications with views, following the Model-View-Controller (MVC) pattern.