ASP.NET Core Web API [.NET 10]: The Complete Guide

Map data from http requests to the parameters of an action method using model binding in asp.net core web api, sourcing data from route, query, header, and body.

Learn how ASP.NET Core Web API validates models between binding and action execution using data annotations. Apply attributes like required, range, url, and compare to auto-generate clear JSON error messages.

Implement the update shared endpoint in the in-memory web API by validating IDs, updating the shirt in the shared repository, and returning 204 on success or 404/400 for errors.

Install and verify three EF Core NuGet packages—Entity Framework Core.SqlServer, Entity Framework Core.Tools, and Entity Framework Core.Design—within a .NET project, then confirm they appear in the project file.

Implement a get by id endpoint with EF Core and SQL Server, using an action filter and constructor injection to validate shirt existence via the shared repository.

Implement a post endpoint with entity framework core, replacing the in-memory repository, inject the application db context, use lower-case comparison, and persist new shirts via change tracker and save changes.

Add an ASP.NET Core MVC project to the solution and set it as the startup project to consume existing web api endpoints. The default template includes homepage and privacy page.

Add a shirts page to display a list of shirts using an mvc shirts controller and a razor view, using an in-memory repository and bootstrap table; no api calls yet.

Implement MVC form validation in .NET 10 by showing model-based errors with a validation summary and tag helpers, and display field-level messages for brand, gender, color, size, and price.

Post a new shirt via the web api to the shirts endpoint, validate the model state, and redirect to the shirts index after successful creation in the database.

Implement a helper method to handle web API exceptions, add the error to the model state, and display it on the update shirt view.

Explore how authentication, token-based authorization, and token verification secure web api endpoints, with an application, authority, and resource exchanging a client id, secret, and token.

Authenticate apps against authority by posting app credentials to an authority endpoint, validating via the app repository, and returning an access token with a 10-minute expiry.

refactor authentication logic by extracting authenticate and create token into a static authenticator class, update authority controller calls, and validate with postman to ensure functionality remains unchanged.

Learn to save a jwt token in session backed by a cookie and reuse it to avoid authenticating the token on every request, using http context accessor to access session.

Install two NuGet packages to support versioning for controller style web api endpoints: ASP versioning MVC and ASP versioning MVC API explorer.

add swagger document support to a web api by installing swashbuckle and open api packages, configuring middleware, and enabling swagger ui in development to document and explore endpoints.

Introduce a second version of the web API by adding a required description to the shirt class, plus a v2 validate description method and an ensure description is present filter.

Configure API versioning to support multiple versions by setting a default version and routes, ensuring existing clients stay functional while validating with Postman and bearer tokens.

Enable API version reporting in program.cs with options.reportApiVersions = true. After running the app, Postman headers show available versions 1.0 and 2.0; default is 1.0.

Explore route-based versioning in .net web APIs by configuring v1.0 and v2.0 routes in the shirts controller, and verify supported versions in the response header.

Learn how to version a .NET web API using a query string, compare header and route approaches, and verify updates across versions with practical examples.