4 min read
What Is an API? REST and ASP.NET Core Examples
What is an API — definition, how REST APIs work, request/response flow, and a minimal ASP.NET Core example. Plain English before framework details.
Blog topic
Article map for REST API design on ASP.NET Core — links to definitions, principles checklist, OpenAPI/Swagger, and Angular contracts.
API design is the contract Angular, mobile, and partner clients depend on. Start with what is an API, then API design principles.
This page is the article map for REST API design on ASP.NET Core. Definitions, checklists, and OpenAPI tooling each own their own URL.
| You want… | Open |
|---|---|
| What is an API | What is an API |
| API design principles checklist | API design principles |
| Swagger vs OpenAPI / Swashbuckle | Swagger vs OpenAPI |
| Validation envelope for Angular | FluentValidation |
| Angular + .NET contracts | Angular + .NET integration |
Open the linked guides for depth — this index does not replace them.
Related: Architecture · Auth & Tokens · Interview Questions
Plain definition: what is an API. Production checklist: API design principles. This page indexes the cluster.
4 min read
What is an API — definition, how REST APIs work, request/response flow, and a minimal ASP.NET Core example. Plain English before framework details.
Updated Published 6 min read
API design principles for production REST APIs — resource naming, versioning, errors, pagination, auth, and idempotency with ASP.NET Core examples.
Updated Published 21 min read
Swagger is the UI name; OpenAPI is the document. Say both on a README. Package choice lives at /blog/dotnet-9-openapi-vs-swashbuckle, not on this page.
Updated Published 12 min read
FluentValidation in ASP.NET Core without the deprecated AspNetCore package — one ProblemDetails envelope, field errors Angular forms can bind, and validation in ASP.NET APIs.
Updated Published 6 min read
Set up ASP.NET Core global exception handling with ProblemDetails so Angular forms show consistent errors — middleware vs IExceptionHandler, 400 vs 500, and what not to leak.
Updated Published 6 min read
ASP.NET Core Minimal APIs guide — MapGet, MapGroup, DI, validation, OpenAPI, JWT auth, and when controllers still win for Angular-backed products.
Updated Published 8 min read
Angular and ASP.NET Core integration habits — DTO contracts, error envelopes, pagination metadata, datetime policy, and CORS decisions that stop rework.
8 min read
API design interview prep for .NET developers. REST design, idempotency, pagination, versioning, and rate limiting — with 30-second and strong answers.
9 min read
.NET 9 built-in OpenAPI versus Swashbuckle: who writes the document, who only draws a UI, and where NSwag or Scalar still fits. Do not run two generators.
10 min read
.NET 10 ASP.NET Core new features for APIs: Minimal API validation, OpenAPI 3.1, cookie 401s, and the transformer compile break after you upgrade.
10 min read
ASP.NET Core WebSockets vs SignalR: choose SignalR for groups and reconnect, or raw sockets when you must own the frames, auth, and scale-out.
9 min read
Enable ASP.NET Core request decompression so gzip, Brotli, or deflate bodies bind as normal JSON, and cap the inflated size. Not response compression.
10 min read
ASP.NET Core rate limiting vs Polly: return 429 before the action, and limit outbound HttpClient calls in Polly. Most APIs need both, for different budgets.
11 min read
ASP.NET Core file download streaming for large CSV exports: async EF rows, an early flush, cancellation, and a one-time ticket instead of a query JWT.
10 min read
Download a file with Angular HttpClient as a blob from an ASP.NET Core API, and report upload progress, without parsing that file body as JSON.
12 min read
Accessible Angular forms with aria-live: labels, ASP.NET Core field errors, and a live region that already exists when @defer swaps content in.
10 min read
RFC 9457 ProblemDetails in ASP.NET Core — standard error responses, extension fields, Angular error parsing, and client-friendly formats.
9 min read
Hot Chocolate GraphQL in ASP.NET Core — schema definition, queries, mutations, subscriptions, and auth integration patterns.
Updated Published 5 min read
Stop duplicate orders with idempotency keys in ASP.NET Core — store the Idempotency-Key header with the response and replay safely for duplicate requests.
3 min read
Offset page numbers skip and duplicate rows when the table changes. Cursor pagination for an ASP.NET Core list API is a key, a stable order, and a next link Angular can follow.
Updated Published 5 min read
Implement end-to-end request tracing in ASP.NET Core with custom CorrelationIdMiddleware, ILogger scopes, W3C traceparent headers, and Angular HTTP interceptors.
Updated Published 5 min read
Implement API versioning in ASP.NET Core with Asp.Versioning.Http, URL/Header strategies, OpenAPI Swagger docs, and deprecation sunset headers.
Updated Published 7 min read
Microsoft.AspNetCore.RateLimiting in ASP.NET Core — fixed/sliding windows, per-user policies, 429 responses for Angular clients, and multi-instance pitfalls.
6 min read
Use IHttpClientFactory in ASP.NET Core to avoid HttpClient socket exhaustion and stale DNS — named clients, typed clients, Polly retries, and mistakes that still break production APIs.
Updated Published 5 min read
Fix System.Text.Json object cycle detected in ASP.NET Core — EF navigation graphs, why ReferenceHandler.Preserve breaks Angular, and DTO projection that actually ships.
Updated Published 9 min read
ASP.NET Core JWT checklist for issuance, validation, and token lifetimes only. Refresh rotation and the Angular interceptor each have their own post.
7 min read
Backend-for-Frontend BFF pattern with ASP.NET Core, Angular, and YARP — cookie sessions, server-side tokens, CSRF defense, and when to skip SPA-held JWTs.