ASP.NET Web API (.NET Framework) Tutorial

Write an action GET api/reports/sales that binds a [FromUri] SalesQuery with From and To (DateTime) and Region (string, optional), and returns them back. What query string calls it?

Write an UpdatePriceDto with only NewPrice, and an action PUT api/products/{id}/price that applies it to the entity and returns a ProductListItemDto-like anonymous object.

Create a RegisterRequest with Email ([Required], [EmailAddress]), Password ([Required], [StringLength(64, MinimumLength = 8)]) and Age (int? with [Range(13, 120)]). Write an action that returns 400 with ModelState when invalid.

Register an ITaxCalculator (implemented by GstCalculator, 18%) as SingleInstance, and write a TaxController that receives it and returns the tax for GET api/tax/{amount}.

Write an ICouponService with ApplyCoupon(string code, decimal total) that throws BusinessRuleException for unknown codes and returns the discounted total for "SAVE10" (10% off). Write a controller action that returns 200 with the new total or 400 with the message.

Write an async method UpdateStockAsync(int productId, int newStock) that runs an UPDATE with parameters and returns true if a row was changed.

Write an action GET api/categories/summary that returns each category name with its product count and average price, using one EF6 query.

Write the CREATE TABLE for dbo.Orders: Id identity PK, ProductId FK to Products, Quantity (1–10 via CHECK), Total DECIMAL(18,2), CreatedAt UTC default, plus an index for “orders of a product, newest first”.

Call a procedure dbo.usp_SearchProducts @Term NVARCHAR(50) that returns Id, Name, Price, using EF6 Database.SqlQuery into a ProductRow class, and return the list from GET api/products/proc-search?term=pen.

Add PATCH api/products/{id}/stock that receives { "Change": -3 } and adjusts stock, returning 409 if stock would go below 0.

Implement keyset pagination: GET api/orders?afterId=4000&limit=20 returns up to 20 orders with Id > afterId ordered by Id, plus nextAfterId (the last Id, or null when there are no more).

Add a createdAfter (DateTime?) filter and a "stock" sort option (lowest stock first unless desc=true) to the filter above.

Support multi-word search: q="blue pen" should return products whose Name contains every word. Write the query-building part.

Extend the exception filter so that UnauthorizedAccessException returns 403 with {"message":"You do not have access to this resource."}.

Add a warning log to an action GET api/products/{id}/stock when stock is below 5, including ProductId and Stock as properties.

Document a POST api/products action: summary, a [ResponseType(typeof(ProductDto))], and response comments for 201 and 400.

Add an [AllowAnonymous] action GET api/profile/public-info inside the [Authorize] ProfileController that returns { app = "Shop" } without a token.

Write GET api/orders/{id} that returns 404 if the order does not exist, 403 if it belongs to another user (unless the caller is Admin), and 200 otherwise. Orders are a static Dictionary<int, string> of id → owner user name.

Read allowed origins from Web.config appSettings key "Cors:Origins" (comma-separated) instead of hard-coding them.

Add an OrdersController in a V2 namespace with [ApiVersion("2.0")] whose GET api/v2/orders/{id} returns { Id, Status, Items = new string[0] }.

Write a CorrelationIdHandler that reads an X-Correlation-Id request header (or creates a new GUID), stores it in request.Properties["CorrelationId"], and adds it to the response headers.

Write a helper IsAllowedImage(string fileName, long size) that returns true only for .jpg/.jpeg/.png up to 2 MB, and use it in an upload action for profile photos.

Write curl commands that (1) update product 1’s name with PUT, (2) request page 2 with pageSize 5, and (3) check that pageSize=1000 is capped.

Write a test proving that Get returns NotFoundResult when the service throws nothing but returns null for id 0, and a test that the service is called exactly once.

Add an integration test proving that a request with an Accept: application/json header returns Content-Type application/json.

Cache the result of an expensive GetDashboardStatsAsync() for 30 seconds in MemoryCache, using a helper GetOrAddAsync(key, factory, seconds).

Write an extension method EnsureOwner(this ApiController controller, string ownerUserName) that throws HttpResponseException with 404 when the current user is not the owner (404 hides that the resource exists).

Write a Web.Staging.config transform that sets the ShopDb connection string to Server=sql-staging;Database=Shop;Integrated Security=True; and Environment to Staging.

Write az commands that (1) add an app setting FeatureFlags:NewCheckout=true to the staging slot only and (2) stream the production logs.

Convert the TimingHandler from the Message Handlers lesson into ASP.NET Core middleware that adds an X-Response-Time-ms header.