The simplest way to create an API is with .NET | Minimal APIs

[@dougelk3]

Thanks!

[@AlFasGD]

You've successfully made me wanna touch building APIs. I have always been avoiding them and sticking to my area, which is building libraries and now code analyzers, but the simplicity of properly building a functional API appeals to me like it's never done before.

[@dsvechnikov]

That's simple until you get to authentication, authorization, validation and other stuff that must be implemented in 99% of real production applications

[@johnnyt.2523]

I started watching your other series where you created the api in the old way, and I didn't really understand how it worked(coming from Django, java). It was the most professional and well structured series I've ever seen! Hope you make a more beginner friendly series explaining the C# and architecture used.

[@okbrown]

Beautiful!!! This makes me so happy!! (Says the NodeJS Developer in me!!)

[@cethrivias]

Amazing! I think that this is a great entry point for somebody who just wants to try to write some basic api in dotnet

[@bennymountain1]

Cool! Now I need to know even less stuff to do my job!

[@Lyokou]

My mind is literally blown away. My biggest frustration with C# is how verbose it is compared to PHP, JavaScript, and Python, and the compiler on change, so annoying. This really makes me want to use now, so excited to play with it.

[@cembobiohazard7779]

short and sweet. Thanks man 👍

[@peymannaji]

Thanks for the video, I think one of the good use cases for this feature would be creating a mock server or a test API, otherwise I still would choose the old approach for production.

[@davidpereira5303]

Really well explained, thanks👌!

[@mohamedsalah324]

Your videos helps a lot thanks for the great stuff

[@rockymarquiss8327]

Nice.. Thank you for your demonstration!

[@alexvanheerden5702]

1. This was amazing 2. Seeing you use Visual Studio was quite jarring 😜

[@StephenBeale]

A helpful video, as always, but when I follow along, why does mine need using statements and yours does not? I am using a .NET 6 console app project type - I can't see any icons in any project type that match yours. What type of project are you using? And even when I do add the suggested using statement for Microsoft.Graph.Models, the same builder function is not available. Any help/clarity would be much appreciated. Thanks, Steve

[@darianferrer]

At first I thought it would change dramatically how we structure a project, but on second thought, I think it won't change too much actually (at least for microservices): following your example, I would have a static class CustomersApi, with static methods GetAll, GetById, etc that will be passed to app.MapGet, etc. That way testability for the new "controller" is easy to do, and the rest of the code can be organised in the same way you are used to.

[@nickchapsas]

That's exactly it. And the cool thing is that this type of routing is more performant than Controller routing so you also get a free performance boost for virtually minimal (no pun intented) change

[@lolyasuo1235]

@@nickchapsas If im not wrong you could use Configure > IApplicationBuilder app to have routing in Startup.cs. I don't know what is happening in the behind, but you always could do this. Ofc the new approach is much cleaner...

[@darianferrer]

@@lolyasuo1235 you are right, it's almost the same thing, but with this new style you get DI by default for example, in the old style you only get the http context (though you can get the service with that) and the configuration here is smaller (lots of defaults of course). The point is, it's great for teaching, PoC, even microservices in real live if defaults are enough

[@davidfowl]

@@darianferrer It's the same tech under the covers and it's as capable as whatever you were using in the past. This new API is a cleaner way to remove boilerplate for common scenarios.

[@darianferrer]

@@davidfowl I agree, seems to be built in what's already in .NET Core, but I was thinking for big monolithic apps which can have lots of controllers, I would still prefer the routing attributes, but that's a personal choice and probably very influenced by me not using this new style yet :D I will still try it because 99% of the time I work with microservices and this seems very good for that

[@katsmike853]

Hey Nick, I was wandering, how would you go about enabling authentication/authorization on this type of an API web app ?

[@nickchapsas]

It's the exact same as in normal MVC. It's just that instead of having to configure it in Startup.cs you can configure it with builder.Services.AddAuthentication() and app.UseAuthentication()

[@codeme8016]

@@nickchapsas Hey there, how would you apply [Authorize] to a single controller endpoint?

[@sky_walker_]

Which usings and dlls i need? I dont find the webapplication class.

[@StephenBeale]

ditto

[@Mirko_G.]

Thank you Mom Microsoft ! We truly love you ! I will try some spikes with Soc

[@basitameen6156]

can you do a series on architectural and design patterns for microservices stack

[@saadbinsami4801]

Hi Nick, Can you please do a comparative analysis on Memory and T [ ] ?

[@rosspovey1869]

LOVE this! Thank you!

[@lardosian]

Cool, gonna wait till November, knowing my luck I would mess things up with preview versions etc!!

[@TransparentWorld1275]

Is there any advantage to building APIs the older way, besides having more (possibly) organization?

[@morgadoapi4431]

Nick or anyone else correct me if I'm wrong or agree with me. I would see how this is useful for a prototype or very simple application. Introducing this new way of writing APIs in an ENTERPRISE setting comes with a couple of drawbacks. 1. Your developers have to learn new skills to do what they already knew how to do with the conventional way 2. You should build your prototypes as closely to production ready as pragmatically possible, the code should be as close to the existing architecture as possible 3. You lose testability, then again this is not intended for business logic applications only CRUD and manual testing on small endpoints is ok 4. You have limited extensibility because of a simplistic architecture 5. Security has to be simplistic you lose flexibility in this aspect If you keep these things in mind you will have a great time with Minimal APIs.

[@nickchapsas]

Check my “in defence of minima apis” video

[@vert3cx373]

Thanks Nick!

[@JesseUnderscoreMartin]

Hi Nick, at 14:00 it sounds as if you mentioned that this can do 800,000 requests per second. Do you have more information about this, or a source? I may be misunderstanding something. I've been looking at Node vs Go REST benchmarks and they're all in the 4,000-10,000 request per second range.

[@nickchapsas]

They are plain text responses, Maria Nagaga’s (Microsoft) demo had that slide

[@JesseUnderscoreMartin]

@@nickchapsas Got it, thanks Nick! And thanks for the vid!

[@JesseUnderscoreMartin]

20:00 in this video (kzbin.info/www/bejne/Z5XEgHd8pZurrNU) if anyone else is interested, that's a pretty big increase!

[@MaxPlayle]

10:20 @Nick Chapsas How would I interact with the Query String using this method? Thanks in advance :)

[@romafedor2590]

Nick please do something with monitors/timeout monitors ! Thank you!

[@EduardoAG]

9:20 I guess you can use Global Usings and move the usings on a single separate file

[@ronaldoperes1202]

How to create a minimal API folder structure? I don't see the "public static void main()" What template do you use in Visual Studio?

[@nickchapsas]

No template. Just a blank console app. public static void isn't neede anymore. It's just infered in the Program.cs

[@ronaldoperes1202]

@@nickchapsas ok, and is that only for Dotnet core 6?

[@jakebradminster709]

Excellent, now I can simplify all my 'Hello World' APIs.

[@techman6713]

Hi Nick! Thanks for the video, I have a simple question: is it possible to separate routing to another file, like in Angular?

[@nickchapsas]

Sure thing

[@lollo4711]

In another presentation for this “new style” - the question if the compiled assembly size will also shrink was answered with NO (which sounded like a pre-compiler that transforms “new style” into “old style” code) @2:11 you say: bitcode gets smaller - but the total size of the compiled assembly remains the same?

[@nickchapsas]

So that's partially true. The code will get lowered and top level statements and all the cool features will be lowered to the old style which means more code in the packaged version but Minimal APIs the feature, won't get lowered to old MVC style

[@lollo4711]

@@nickchapsas Tnx 4 your answer. Another example came along with no (visible) “void Main()”. How can “void Main()” be made async/sync? Thinking about costs in the cloud (every flop counts;) it would have been really awesome just to start a Web-API with three lines of code - but the code-creator hides a lot of stuff done in the background. So, I would recommend a dotnet-cmd compiler-option to output the fully generated (old style) code.

[@nickchapsas]

@@lollo4711 You can totally use async in that method. for example if you wanna use the app.RunAsync() method to run the app, you can just to "await app.RunAsync()" and the code will automatically detect it and accept it. Not that it will make any difference in that specific usecase, but it's totally acceptable if you wanna use it.

[@AdisonCavani]

What's your thoughts about "new" VS Studio 2022 Preview? I think it's a big improvement over the previous one. Everything runs much faster, especially intelliSense and startup

[@nickchapsas]

At least on my PC it still runs quite a bit slower than Rider. It's just less snappy. It might be something that I can probably configure, plus it's still in preview, but for now, I can't see myself switching.

[@djmotion86]

2022 freezes quite a bit after waking up from sleep

[@pabloturnesg]

Nick do you or your team ocasionally use linked lists?

[@LindenMikus]

can you do push notifications with this?

[@20windfisch11]

Will Blazor also use the newer simple API?

[@m.wilusz964]

How it's possible that '_customers[id];' in GetById don't throw but return null?

[@codeme8016]

I feel in order to skip every single simple Controller I have to add a lot of extra codes/files in order to achieve the same thing. e.g. validating data. What's the point of using Minimal API now? Am I missing something?

[@lukmankazeem2188]

Dayummmm man, you make it make sense, make sense?

[@Layarion]

i'll have to come back to this later, kinda just glazing over me right now. is there a more birds-eye view with wireframe examples of what this is about?

[@ofc2463]

What could be the use of this Minimal APIs? For demo/learning or can it be used in production?

[@nickchapsas]

Can be used in production

[@mmaranta785]

That is one huge computer you are sitting in front of

[@swathivallabhani6320]

Hi Nick, How can i get data from sql in this concepts?? Do you have any example ???

[@nickchapsas]

In other videos about Minimal APIs yeah

[@paulcappello5931]

I like this. Reminds me of Perl Dancer

[@pavanchandu6172]

what about Swashbuckle and swagger injection in the simple API? Is it feasible

[@nickchapsas]

I should have shown it. It's the same thing as the full api. You need to add the swagger gen and the middleware with app.UseSwagger() and app.UseSwaggerUI()

[@ripple123]

you can check out a dotnet standup with david fowler and others about minimal apis where they go into more detail about this new approach

[@parlor3115]

I kinda knew this would happen since they started to refer to dotnet application as "app". Also, isn't that a C# script. Like there are no using statements and all.

[@nickchapsas]

This is just C#, not C# script. They changed it so a lot of using statements can be automatically infered without the need to be explicitly stated

[@godfather7695]

If your api have just one function it is very good, but if you need make som checks or you have n layer architecture...🤔

[@megaman2016]

Where is the port defined?,

[@snokzor]

Pretty cool stuff. How is this so much faster tho?

[@nickchapsas]

It’s doing less

[@naveenmishra1778]

my question is, can a Minimal APIs concept be used in large complex applications

[@Vastlee]

The evil twin Tom Chapsas!

[@Morzelius]

How those APIs can be used in a real-world project? I mean, it looks fancy on a tutorial. But I don't see how the program can be structured on a large project.

[@Maric18]

tbh the simplest way i have seen to build apis is python-flask but this is cool as well :D

[@ortundgaming967]

What project type am I using for this? dotnet new webapi dotnet new web dotnet new console dotnet new classlib You didn't show D:

[@davidfowl]

dotnet new web

[@JohnZakaria]

Nothing beats fastapi in its simplicity

[@nickchapsas]

Looking at their hello world example, it looks longer

[@JohnZakaria]

Well you get free swagger UI. Type checking in python too.

[@shreyasjejurkar1233]

@@JohnZakaria nothing comes as free. Swagger ui is there in here as well, but it's option for developer to have it or not.

[@obinnaokafor6252]

@@JohnZakaria C# is strongly typed. Lol

[@goodoleme747]

Simple in Go as well.

[@hasan-ceo]

Awesome! Do I need to map all my 100+ end point in single file?

[@davidfowl]

You can if you want to sure, you can also use methods.

[@nickchapsas]

Several people asked this. On Tuesday I will be publishing a video that shows how you can structure a minimal api in a more elegant way. These videos are supposed to show you how things work and how to get started. You should never think that this is all there is to it and that’s true for things outside of minimal APIs too

[@joe-sydney-au]

Can you please show a more complicated example, where the API returns a custom Http Status Code and Message (say, for example 422) and capture it with any client-side library (e.g. the Browser's built-in fetch)? Now that's an idea for a video (if you haven't done one already).

[@toebeann]

For that, from the handler you would return, e.g. Results.Text("Something went wrong! Oh noes!", statusCode: 422)

[@toebeann]

Most of the Results methods have an overload which accepts an int representing a status code. e.g. Results.Json, Results.Content, Results.Text to name a few. There's also the Results.StatusCode method which accepts just an int argument and will not output any body in the response, just the status code.

[@TonoNamnum]

Does anyone know how to access the httpContext in order to add a custom header as a response for example?

[@AvgDan]

What's the cleanest way to add an API server to a Windows Forms app?

[@filipecotrimmelo7714]

Ow nice, but I want to see it a real small application. This example with customers is just a hello world. But I love the content and see what is new.

[@avtargill]

Agreed. I'd pay for a course that covered a full app (authentication, database, etc.), preferably with tests.

[@godfather7695]

I think single responsibility principle is not working here. Class Program must response only one job is to run midleware and application🤔

[@Gameplayer55055]

While you're building a simple APIs, i suffer from problems with tls 1.3 support.

[@mahesh_rcb]

What else is possible in Minimal API .. Out of curiosity 😅 Most demos have CRUD

[@nickchapsas]

Well anything really. The reason why most demos use crud is to compare it with how less boilerplate code you have compared to full MVC. The rest is the same.

[@antonkomyshan1727]

Rider doesn't support C# 10 yet?

[@shreyasjejurkar1233]

.NET 6 & C# 10 isn't GA yet!

[@CRBarchager]

C# 10 is sceduled to be released in November 2021 so no Rider doesn't not support it.... yet!

[@MaZe741]

800'000 requests a second? thats almost a thousandth of a millisecond, how did you get to this number?

[@nickchapsas]

It’s the number Microsoft gets in there JSON TechEmpowered benchmarks

[@MaZe741]

@@nickchapsas I doubt you can even make a db call in that time, please link the source, its just so unrealistic and depends on so many factors like network latency. you sure this isnt "per minute", for example?

[@MaZe741]

@@nickchapsas also, your demo at 13:14 shows 11ms and 10ms, I dont understand how you would improve this by a factor of 10'000 without some serious scaling solutions like containers, workers or load balancers. There's something else missing here, it cannot just be fastapi by itself working at almost a million requests a second. just nope. And this isnt even connected to a real database yet.

[@CrapE_DM]

My biggest thing is TDD. So I would create those functions separately to be testable. But yeah, they've got something similar in Kotlin, and I think Java Spark comes close, too.

[@Mirko_G.]

Me too! Im developing rest apis with tdd and Soc its part of that!

[@John_FritzTheCat_Doe]

The quickest and shortest API setup you can get is with Python + FastAPI. I'm pretty sure Microsoft has copied that concept (like everything) for their minimal api's.

[@nickchapsas]

Is it though? FastAPI Hello world is 5 lines of code. Minimal APIs in .NET is 3.

[@DiegoNovati1]

No different from Quarkus, that you can deploy as native or with Java runtime

[@nickchapsas]

I don't know about that. This looks pretty verbose to me: quarkus.io/guides/getting-started#the-jax-rs-resources

[@DiegoNovati1]

@@nickchapsas The Java code is more verbose than the Kotlin one, but at the same level as the code you have written.

[@clearlyunwell]

👍🏽

[@jcorrify]

It's indeed a nice feature for quick work, but I wonder how it will turn out with a real-life situation with a full rest API capability implementing swagger documentation, media types validation, hateoas, authentication, etc... I suspect it will turn into a large unreadable mono file...

[@ySomic]

It's more as an introductionary for new programmers or people that are new to .NET. Making it easy to be immersed into .NET. which will really propell the framework (and C#) forward.

[@davidfowl]

Show me your controller with all of those things and I'll show you the minimal API equivalent.

[@obinnaokafor6252]

@@davidfowl ❤️❤️❤️❤️

[@FilmfanOliver1992]

I like ASP Net Core as much as Spring Boot :-)

[@KangoV]

Nice that you expose your internal database structure through a HTTP interface. If I saw a developer working for me do that, I'd haul him/her over the coals. This kind of example is teachinf developers very bad habits. Oh I just tried this and did it in around 67 lines of Java code.

[@greyedout]

Where exactly did he expose the database structure in HTTP? I somehow missed that part?

[@greyedout]

For anyone also wondering, I was being sarcastic. There is exactly nothing wrong with the code and no "internal database structure" is exposed through a "HTTP" interface. What he probably meant is that he is returning the "database models" without using a DTO. Which is out of scope for this video and also I doubt the 67 line Java code has it implemented.

[@denis-suleimanov]

Well... What if I have a many entities? Controllers - is more or less "strong" structure. And now... microsoft told me "hey! Add all of your endpoints and their handlers to single file".. Thanks, but no. What about multiple attributes (cached, authority, access model..)? Multiline handlers, etc? I think C# is going to wrong path... "divide et impera" isn't?

[@nickchapsas]

You don't need to have everything in a single file. This can still be "structured" without the need for a controller. Just because those MapGet methods can be in the Program.cs doesn't mean that you can't give them proper structure and move them in a different place. It's more about what you could do not what you should do.

[@CRBarchager]

Almost any tutorial will not should you the most optimal way of doing things. Just demonstrate a function or a way to do things. Doing it "the right way" will obviously make this video alot longer not having it cramped down into a 15 minute snippet. But Nick gets the meaning out perfectly and it really shows how far .NET have come.

[@denis-suleimanov]

​@@CRBarchager hmm... I don't have any problem with this video or Nick or even Microsoft as a company.. I was saying just about new conception, nothing more.

[@obinnaokafor6252]

Microsoft never told you that.

[@CobeinCobein]

Looks like nancyfx

[@chadiusmaximus9350]

you are 100% correct. the Nancy devs went on to create Carter which is the successor to Nancy. David Flower and the ASP.Net Core team took alot inspiration for this team.

[@miatribe]

Now add some security to it.

[@void_star_void]

I'm of two worlds about this. More like a love hate relationship

[@nickchapsas]

The great thing about it is that it's completely optional

[@lolyasuo1235]

@@nickchapsas Seems like they have changed all templates to use the minimal api approach. Even console template is 1 line with just Console.WriteLine()... which personally i don't like it. I don't think there is any real use that will benefit from not having main method. Even a student assignment will propably have 3-4 methods for solving the problem... so you will end up manually adding the old main method. (ofc you can ignore main and just add other methods. but i prefer the old style). Minimal api is a good approach for easy and fast web apis but not for other things. My opinion ofc. I don't like the "scriptish" languages. I would prefer the Visual Studio templates to remain the same and just have variations for the minimal apis.

[@chriskeo392]

FastAPI beats this by a mile

[@nickchapsas]

In what? Performance? lolno, even on FastAPI's own benchmarks, ASP.NET is faster

[@AnonymousDeveloper1]

I don't like top-level statements stuff and well minimal API seems to be very strange at the first time. It looks like being taken from Express.js which I like however I'm not sure if it's good to have everything in just one file. It only works in "tutorial hello world" videos and not even slightly bigger application. Could you show us example where you don't write everything in Program.cs? Just split the code and make it clean with interfaces, services, configuration, AutoMapper, entity framework core...

[@nickchapsas]

No one ever said that minimal APIs mean that you should have everything in one file. Check my “In defence of minimal APIs” video

[@AnonymousDeveloper1]

@@nickchapsas Thanks, I'll watch this video soon. Generally speaking I'd like to see examples which don't show everything in just one file. I wish .NET designers, Microsoft and community guys will show easy and detailed tutorials in the future. So many questions, not so many answers.

[@luderx]

But anyway, who uses Microsoft Java?

[@anotherme4638]

Wait a minute, Is this actually .NET 6 C# ? it feels like python or nodeJS thanks man for the demo.

[@bennymountain1]

They've made it so if you don't declare class and static Main method in a file it generates when you build your app, if that's what you mean. I think this was in since .net 5. Handy for a "hello world", but I haven't used it, honestly.

[@stepanhakobyan]

The second part of the video shows how to get some unmaintainable code. Enjoy.

[@nickchapsas]

You don’t have to keep everything in a single file. You can structure it like any other project. The only thing that changes is the entry point and you get routing performance over controller for free.

[@twiksify]

How would one go about unit testing such an endpoint? As I see it you no longer have a dedicated method, instead you'll have to launch the app in order to expose the endpoint in form of an API call. The lambda can be replaced with a testable method call, however how can I verify that the method is configured for the right API endpoint path as well as that the method isn't falsely being used by another endpoint? Selenium can be used for integration tests, however it'll be rather hard to maintain mocks for unit test of an endpoint which you don't have the entry point context.

[@yearlyoatmeal]

This guys style and content is absolutely on point but at times the speed with which he speaks combines with his accent in a way that can make it just a little bit exhausting to follow. I wished he would either slow down just a tiny bit, or alternatively try to improve his pronunciation. Not wanting to be rude or ungrateful here!! He's the best C# content source on KZbin imo but that's kind of why I'm taking the time to provide this unsolicited feedback here.. anyways, thanks for all the fantastic free content and insights! Keep it up. 🍺

[@nickchapsas]

So, this is kind of the double edge sword of this type of content creation. Long videos just dont' get clicked and I have plenty of data to back that up. If I do talk slower, then the video will get longer and it will definately cross that threshold. The majority of the comments I get about the content's pace is positive, mainly because the people who watch my content are intermediate to advance levels. Ofc that means that when I do a more entry level video like this one I will inevitably be too fast for some people, and you're right me accent doesn't help. Ultimately if people think it's too fast, they can use the KZbin speed controls to slow that down. I'd rather have people slow a video down than people speed a video up.

[@pilotboba]

You can speed up or slow down the You Tube play back. I watch most things like this at 1.5x or 1.75x.

[@yearlyoatmeal]

@@nickchapsas fair enough!! Yeah I can see that too fast for some is probably better than the opposite. For example Tim Corey tutorials are basically unwatchable due to their mind numbing snail pace. That guy can take a half hour to explain something that should take a minute... Thanks again for providing such great value!!

[@zedmagdy]

: Am I a joke to you bro?

[@obinnaokafor6252]

--OR-- Console.WriteLine("Hello, World);

[@zedmagdy]

@@obinnaokafor6252 You just forgot to add .csproj file so it's not gonna work

[@obinnaokafor6252]

@@zedmagdy csproj adds itself

[@nanvlad]

Waiting for 'import' and 'export' directives to include .cs files into a main module :)

[@fulmetalmage]

Cute. I can see it being useful for faas or micro services. However i think it will turn into a shitshow in a monolythic api.

[@nickchapsas]

What I am interested to see is how people will decide to "structure" this approach. It is meant to be really easy to get started but in order to become managable and not violate the principles we like using, it will probably need some grooming.

[@Insel03]

@@nickchapsas I imagine I would create a project per resource/domain where I can pass my app builder into. This new approach really would make it a blast to build API modules. Is there proper middleware support?

[@davidfowl]

@@Insel03 It supports all of ASP.NET Core, all of the features.

[@abdelhaleemalfreihat7261]

so what is the point? we all know we use .net for enterprise projects not for building hello world applications!, I think .net development team just trying to make it work in all ways and having as many features as possible, I don't like it :)

[@nickchapsas]

Well that's not true. Enterprise projects doesn't mean big code bases. I am working on "enterprise projects" but I can totally see myself using Minimap APIs for them. Simplifying the entry point and giving a 40% performance increase over the MVC approach is something I just can't resist. It's the thing that the entry point calls that hide the complexity, not the entry point itself. That's why it works.

[@lolyasuo1235]

@@nickchapsas Where 40% performance comes from? is it from the minimal apis approach or from the NET 6 in general? Yea i see a chance for minimal apis in production. You can put em behind some APIM for protection and youre fine.

[@nickchapsas]

@@lolyasuo1235 It comes from the routing. Controller routing is more complicated and less performant compared to Minimal API routing

[@davidfowl]

@@nickchapsas Right, it comes from doing less :)

[@manuillo94]

100% of th15:18

[@ivancarmenates84]

All that is good but wring code sequentially like old fashion programming languages like basic doesn't really makes the point, that is just a mess show.

[@nickchapsas]

Check the followup video

[@scryptum]

This an Express server style. Copy paste !

[@tootytooty5135]

Lol... 0 improvement other than making it into less code which makes it less readable too.

[@AnonymousDeveloper1]

Yes, very bad decision. I was writing about it but they can't understand.