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.NET Web Applications: ASP.NET Core Contracts

Design ASP.NET Core request pipelines, APIs, dependencies, data boundaries, and reliable operations.

18 lessonsEnglish + ArabicContent reviewed
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In this course

This complete web-framework course develops HTTP handling, middleware, routing, Minimal APIs, controllers, dependency injection, configuration, validation, identity, and data-access boundaries. Advanced lessons connect testing, observability, performance, deployment, reliability, and API evolution.

This is distinct from the C# language course: the focus is how ASP.NET Core composes application behavior and operational contracts. Examples use synthetic requests and in-memory framework objects. No configured application, listener, database, external service, or cloud environment is started.

What you will learn

  • Trace request and response behavior through ordered middleware and endpoints.
  • Design explicit DI, options, validation, authentication, and authorization boundaries.
  • Separate EF Core/data-provider behavior from domain and unit-test claims.
  • Verify application contracts and reason about deployment, performance, and recovery.

Your learning path

Three levels

Basic: HTTP and Application Composition

Build clear request, endpoint, controller, and dependency contracts.

  1. Hosting and the HTTP Contract
  2. Middleware Order and Error Boundaries
  3. Routing and Endpoint Selection
  4. Minimal API Binding and Results
  5. Controllers and MVC API Contracts
  6. Dependency Injection and Lifetimes
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Intermediate: Data, Identity, and Asynchronous Work

Connect configuration, validation, identity, persistence, and task lifetimes.

  1. Configuration, Options, and Secret Boundaries
  2. Validation and Problem Details
  3. Authentication Schemes and Trust
  4. Authorization and Resource Boundaries
  5. EF Core and Persistence Boundaries
  6. Async Requests, Cancellation, and Background Work
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Advanced: Verification and Reliable Operations

Review tests, telemetry, performance, deployment, reliability, and API compatibility.

  1. Testing and Evidence Boundaries
  2. Observability and Operational Contracts
  3. Performance, Caching, and Request Limits
  4. Deployment and Proxy Trust
  5. Reliability, Effects, and Retries
  6. API Evolution and Application Boundaries
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Who this is for

  • C# developers learning ASP.NET Core application design.
  • Web developers reviewing request boundaries, DI lifetimes, authorization, and operational reliability.

Before you start

  • Basic C# types, methods, collections, exceptions, and async/await; the public C# course provides that foundation.
  • Basic HTTP concepts help; the basic level explains the request/response model.

Related technical solutions

Resolve Dependency Registration and Scope FailuresIdentify the actual service graph and ownership boundary before changing lifetimes or building another container.Diagnose 404,405, and Binding/Validation FailuresTrace selection, HTTP method, input source, framework validation, and action behavior before adding broad fallback routes.Diagnose 401,403, and Unexpected Authentication OutcomesTrace the selected scheme, trusted principal, policy, resource rule, and HTTP result instead of treating every denial as a login failure.