From

to a dockerized CI/CD

Vedran Mandić, MCSD, MCSA, MCT

 #ATD15, Zagreb 2019-12-05

https://slides.com/vmandic/from-dotnet-new-webapi

dotnet new webapi

...with integration tests

Thank you sponsors

Hi, I am Vedran. 👋

  • I freelance, talk and lecture C# / .NET and JavaScript
  • currently in insurance industry
  • on medium and dev.to by @vekzdran
  • on github by @vmandic
  • bad at basics, suck at CSS, moderate in C#... jk 🙈

What's this presentation about?

Today's plan?

  1. (ASP).NET Core super quick overview
  2. No Visual Studio IDE?
  3. API Design, REST, DDD, Swagger?
  4. demo up a web API with code 👩‍💻
  5. host the demo to a CI/CD provider

First a  bit of .NET Core

.NET Core, an overview

  • open-source (GitHub) cross-platform Runtime and SDK 
  • Current release is 3.1 (Dec 3 2019), started in 2015
  • modern, stable, performing, modular, extensible
  • you can fix bugs, suggest PRs, report issues, ... FIND ANSWERS :-)
  • it is a complete rewrite of .NET Framework; its Core libraries
  • introduced .NET Standard, run side by side with Full framework
  • integrated DI/IoC, Builder pattern, logging, configuration
  • extends with ASP.NET Core, ASP.NET Identity, MVC, Razor Pages, Blazor, EFCore... just search NuGet.org and you got it...
  • you can compile for a dedicated OS, e.g. linux-x64
  • you can compile the whole framework /w app as single .exe

ASP.NET Core?

ASP.NET Core

  • a set of APIs, libraries for building a web apps and services
  • APIs come either separately or in AspNetCore Metapackage
  • comes with its own new server Kestrel, also HTTP.sys
  • can host in IIS, outside it, behind a reverse proxy e.g. Nginx
  • expands design on the OWIN architecture
  • Startup.cs, ConfigureService(), Configure()
  • Go full MVC with filters etc, or go Web API with ControllerBase
  • Razor view, Razor pages, Blazor server side-by-side with Razor
  • compile the app as self-executable and host on any linux server

by the way... we will be building a web API today

$ dotnet new webapi

what's to like?

lol, what's not to like?! :-)

what's to like?

  • dotnet CLI... and dotnet tools!
  • fast builds, logs everything!
  • stability, performance and openness for extensiblity
  • fantastic docs and GitHub support
  • learn from MSDN docs 80%, 10% from blogs, and 10% from XP
  • my XP: 1 month for basics, 6 months to feel safe
  • great community, lots of books, blogs
  • widespread (open-source) NuGet packages, supported
  • cross-plat and docker friendly, CI/CD happy
  • I learned to appreciate and harness the CLI and linux

Visual Studio IDE?

  • there is... Visual Studio 2017, 2019 and they are better then ever
  • Instead try the open source community VSCode
  • embrace the dotnet CLI, reference projects faster ;-)
  • VSCode is an editor with a ton of extensions and C# support
  • currently I use Visual Studio IDE only for multi test debugging
  • https://visualstudio.microsoft.com/services/visual-studio-online/

Visual Studio Code

Considerations to take when building an API

 possibly > decimal.MaxValue

that's 79,228,162,514,264,337,593,543,950,335 things to think about...

Some things to consider in API design

  • exhaustive logging
  • healthcheck API
  • REST(ful) (as much as possible...🙈) HATEOAS
  • API Documentation (Swagger OpenAPI)
  • CORS policy
  • full control over in and out HTTP headers
  • versioned, rate limited, cached... 
  • Authentication with JWT and claims
  • Multi-authentication
  • Fail unobtrusively and redact error details
  • logic independent to scaling (ACS, k8s, OpenShift pods++)
     
  • Clean Code, Domain Driven Design layered...
  • Open-Closed, SRP, pure as much as possible...
  • Testable, Integration testable, CI/CD-able

That's what you should love about .NET Core, all of it's plug and play

Also Luka Gospodnetić had a wonderful great talk about it yesterday:
 

"Through desert and wilderness to .NET Core Enterprise app"

Swagger (OpenAPI)

demo time!

more sort of a code-review than coding :-)

The end! 📸 Questions?

VEDRAN MANDIĆ

mandic.vedran@gmail.com

@vekzdran @vmandic
https://gitlab.com/vmandic/from-dotnet-new-webapi
https://slides.com/vmandic/from-dotnet-new-webapi