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

Compare minimal APIs and MVC style controllers to build web APIs in .NET, and organize endpoints with shirts and pants controllers by deriving from ControllerBase and decorating with ApiController.

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.

Create custom validation attributes beyond data annotations to validate multiple properties, enforcing size rules—men: size >= 8 and women: size >= 6—via the validation context in a .NET Web API.

Explore how to choose return types for web api endpoints in .NET, switching from string to in-memory data, and using IActionResult to handle 200, 404, and 400 responses.

Implement a read endpoint for shirts using an in-memory data store, a shirt repository, and a get shirts method; verify retrieval with Postman.

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.

Move exception handling in Web API endpoints from try-catch to an exception filter, validating IDs and returning 404 not found when the shirt does not exist.

Implement a delete endpoint by validating the shirt ID, performing a hard delete from the in-memory store, and testing with postman to confirm the updated list.

Learn how EF Core maps objects to a SQL Server database via an orm, and install NuGet packages for EF Core SQL Server, Tools, and Design to manage migrations.

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.

Create the database and shirts table by applying the initial migration to SQL Server, and configure the connection string in app settings for the shirts store management database.

Implement the get shirts endpoint using entity framework core and the application db context, replacing the in-memory shirt repository with a db set and constructor injection, and verify with postman.

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.

Learn how to implement a put endpoint with EF Core by replacing the static repository, validating IDs with action filters, using FirstOrDefault, tracking changes, saving updates, and returning no content.

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.

Build a web api executor with IHttpClientFactory, configure a named http client with headers, implement a generic get method, and inject it into the MVC controller to fetch data.

Use the web api executor to fetch shirts from the api, display them on the mvc shirts page, and verify the read-all shirts endpoint with postman.

Create shirt form in Razor view, connect it from shirts index to the create shirt action with Bootstrap, and implement a post method for brand, color, size, and price.

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.

Update shirt view teaches fetching a shirt by id through a get action, binding it to a razor view, and posting updates from a form in the update shirt page.

Shows updating a shirt through a web api by posting from an mvc action, using http put with id in the URL and shirt data in the body, with validation.

Learn to delete a shirt using a post-based web api call from a form, with a hidden shirt id and a confirmation prompt, then verify via end-to-end testing.

Learn robust error handling in the mvc web api executor by deserializing api error responses, throwing a custom web api exception, and handling post, put, and delete errors.

Display API error messages by catching web API exceptions in the shirts create action, collecting non-null errors, joining them, and showing all errors in the create shirt view’s validation summary.

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

Handle web api exceptions in an mvc app by displaying error messages for delete shirt. Return the index view to preserve modal state and show a red validation summary.

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.

Register apps against the authority to enable authentication in a web api, using a hardcoded in-memory store to simulate registered apps with client id and secret.

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.

Generate a json web token by configuring hmac sha256 signing, building a token descriptor with claims and scopes, and testing token creation with postman.

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 consume secured web API endpoints by authenticating against the authority, obtaining a JWT access token, and attaching it to the HTTP header for each request.

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.

Document and visualize your .NET web API with OpenAPI and Swagger UI, enable OpenAPI support, install the necessary package, and test endpoints and responses.

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

Explore adding a second API version by creating a v2 controller, configuring API versioning and explorer, and addressing OpenAPI/swagger limitations in .NET 10.

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.

Implement an authorization header in Swagger by configuring a security scheme and an operation filter, enabling bearer token authentication for all endpoints in the web API.

Apply versioning to api endpoints to manage data sharing and functionality, scheduling changes so new customers use newer versions while existing ones stay on older versions.

Install the NuGet package for versioning in the web api project by managing NuGet packages, selecting ASP.Net Core MVC versioning, and installing the latest stable release.

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.

Run a database migration to add the description field to the shares table using the package manager console to add migration and update database, then verify the new column.

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.

Learn to enable multi-version swagger documentation in a web api by configuring the swagger ui and endpoint, adding the versioned api explorer, and using a triple v version format.