9 ms·

Using WebAssembly from .NET with Wasmtime

246 points by skellertor 7y ago

jcmontx 7y ago
I know MSFT technologies get a lot of hate here, but ASP.NET Core is pretty awesome. Blazor (the wasm based framework) is innovative and a positive step forward frontend web development. You should leave your prejudices aside and give it a try if you haven't yet.
- sergiotapia 7y ago
  dotnet core is an insanely good sell for any company. seriously take a look at what you can do and forget what you knew about .net of the 2010s.
- kirse 7y ago
  I really like the approach of Blazor wrt WASM, but really dislike having to dump whole code blocks into CSHTML files like I'm writing old ASP.NET Forms again. Something just feels off. Is there any way to isolate those code blocks and import them? EDIT: To answer my own question, this appears to be the solution: https://www.telerik.com/blogs/using-a-code-behind-approach-to-blazor-components https://www.telerik.com/blogs/using-a-code-behind-approach-t...
  - pjmlp 7y ago
    Well there is Blazor components, unless you mean something else.
  - SigmundA 7y ago
    Blazor supports components: https://docs.microsoft.com/en-us/aspnet/core/blazor/components?view=aspnetcore-3.1 https://docs.microsoft.com/en-us/aspnet/core/blazor/componen...
  - angrysaki 7y ago
    ASP.NET Core 3.1 added support for partial classes for Razor Components, so I don't think you need to use the inheritance style code behind anymore. https://gunnarpeipman.com/blazor-partial-page-class/ https://gunnarpeipman.com/blazor-partial-page-class/
  - bob1029 7y ago
    This is something that hosed me up too at first when using Blazor. There is a specific item type in the VS "Add New Item" dialog that is called "Razor Component" with a fancy purple icon next to it. If your files in the solution explorer end in .razor, you are using the correct item type. If your files end in .cshtml, you are going to have a bad time and everything will seem very wrong. At first, I was using the "Add->Razor Page" context menu option assuming this was what I wanted, but it will give you the wrong type of item.
  - manigandham 7y ago
    The latest release (.Net 3.1) finished the partial classes implementation so now you can create a `Comp.razor` template file and a separate `Comp.razor.cs` code-behind file that only contains the code. These are automatically compiled together on build.
- loudmax 7y ago
  > I know MSFT technologies get a lot of hate here Are you reading the same HN as I do? In the last couple of years, I see a lot more positive than negative comments whenever Microsoft comes up. From what I see, Google is the company that gets the most hate on HN. Of course, Microsoft isn't universally loved. There are a lot of people that don't trust them based on their past behavior, and the fact that Windows and Microsoft Office are still an entrenched monopoly. That might not apply to ASP.NET Core, but not everyone is going to let MSFT off the hook.
  - saagarjha 7y ago
    Interestingly, I ran some very rough sentiment analysis of the comments here and it turns out that Apple gets people the most worked up, followed closely by Facebook. Of Apple, Google, Microsoft, Amazon, and Facebook, posts about Microsoft did seem to have the most positive comments.
    - somedangedname 7y ago
      To add to the general din: Apple are the worst. They kept me waiting four months this year for a client's enterprise developer enrolment to complete. When the client were enrolled? Surprise! You can't sign apps for in-house distribution for another two weeks. Not mentioned anywhere when you sign up. I talked to Apple support and they told me to pound sand. My last enquiry to Tim Cook's customer complaints inbox went unanswered.
      - saagarjha 7y ago
        Oh, I remember being hit by this. Agree that it's not well documented; I think it's there to prevent "signing services" from spring up (not that it does a great job…)
    - ksec 7y ago
      I thought it was pretty clear even without any Stats. People know what Microsoft is doing, the good things and Open Sources. They dont use it not because of hate, I think it is 1. It isn't good enough to make the jump into another ecosystem or language yet. 2. Not hating doesn't mean loving them. IE era, that is IE 5 - 6 if you aren't old enough ( Yes, some people still bash WebKit as the new IE and thinks IE era meant IE7... ) along with the pain on early Windows days still hurt a bit, they will have to try harder, and doing so continuously to win those people back. The thing about Apple isn't hate as in Google or Facebook. It is people have high expectations of Apple and demands quality from them, and when they are not up to that high bar, people complain.
- hackinthebochs 7y ago
  Since you seem to have a positive sentiment towards Blazor, can you point me to a good introduction that demonstrates the power and the benefits of the framework, e.g. increased expressiveness, reduced friction, etc? I've looked through a couple of intros but they never seemed to really sell the benefits of it. As someone who loves the C# language and .NET ecosystem I really want to like it but nothing has clicked so far.
  - nwah1 7y ago
    The idea is to unify the development process and tooling on the front-end and the back-end, without suffering from poor performance and constant unnecessary roundtrips over the network. Not to mention, a significant number of people strongly prefer C# to Javascript (and even Typescript). If those two things never bothered you, then you might not understand the benefit, and you can continue to use what you like. In practice, sending the .NET libraries over the network is the major burden of the approach Blazor takes, since the first load will be slow and bandwidth-intensive, even though everything will likely be cached for subsequent visits. However, as the WASM tooling and standards improve, the library sizes will shrink, and less libraries in general will be necessary to accomplish stuff that has been solved at the level of web standards.
    - wvenable 7y ago
      There is also server-side Blazor which doesn't use WASM components but instead uses SignalR to do client/server communication. Both are compatible with the same code base (and components). Server-side Blazor still has overhead but it's different from having to send the .NET libraries over the network.
  - Gene_Parmesan 7y ago
    Attended a Blazor session at MS Build in May. My impression was, Blazor seems like a super cool tool that I will never be able to justify in production. For one, the performance is poor right now. Your options are either to use Signal to send every action over the network, or to deliver the entire .NET libraries along with the page. The size of that download is both impressively small (given the volume of code you're transferring), and also still way too large for me to feel comfortable foisting that on users. Additionally, it requires that your front-end team feels comfortable working in .NET technologies. Ours certainly doesn't, and it would be very hard to sell my director on anything that doesn't maintain the traditional backend/frontend split.
- ailideex 7y ago
  > I know MSFT technologies get a lot of hate here, but ASP.NET Core is pretty awesome. Given how bad an actor they were I guess some people have a hard time forgetting the past.
  - teh_klev 7y ago
    Sure, but on posts where the comments head downhill lubricated by this trope, often the commentators were still in kindergarten during this time. There's a cargo-cult mentality when it comes to accusing M$ of Embrace, Extend and Extinguish. Sure it happened but the folks leaving these comments weren't around at the time working as pro-software developers. I was, it was annoying, but the world didn't implode, and the law kicked in and did mostly its job. So big deal and yawn. MS has a new management, it was "infiltrated" by the right folks in the early to mid 2000's who educated MS from inside and began to set MS on the right track. It takes time, like steering an oil tanker. But MS are a capitalist corporation, just like all the others, they will all do some evil at some point in time on behalf of their bottom line and shareholder dividends, if they think they can get away with it.
- hudo 7y ago
  Its actually Win10 that people hate, dev tools are just fine
- Mountain_Skies 7y ago
  Blazor might pull me back into software development. About five years ago after close to three decades of doing software development, I got tired of seeing so much software being bent and shoved into JavaScript. I absolutely loathe JavaScript so it seemed like a good time to move on to something else, which in my case was IT security. Occasionally I write a tool or two for use by my team but most developer jobs these days require coding in JavaScript so I hadn't given much thought to going back to full time development work. Blazor however has been a joy to work with. My understanding is JavaScript will still be required for a while on most webassembly apps but for my uses I've been able to avoid doing any directly. Maybe in another couple of years the market will change and those who don't want to use JavaScript everywhere and are horrified that even embedded systems are flirting with js, will again have a place in the world.
  - bob1029 7y ago
    I have found similar joys in using Blazor. Once you get past the boilerplate stage, the productivity gains go exponential very quickly. Component reuse + strong typing + no API controllers or JSON contracts = how web development should have always been. I've got elegant LINQ statements right in my component markup. Creating extremely complex tables and views is so trivial with this combination of technologies. I can even subscribe my razor components to CLR events and everything works exactly the way you'd hope it would. The SignalR link between client and server abstracts away a huge bucket of questionable practices, with some potential trade-offs. Perhaps there is some downside I haven't found yet, but at this point I feel I could live with whatever strangeness might begin to emerge from the path I have taken. In my experience, it is not possible to completely eliminate JS from the equation with Blazor. I've had to write a single .js file which I currently use for 3 things: Reading a cookie, writing a cookie and focusing an arbitrary DOM element. The focus concern I could probably alternatively handle with an autofocus attr which is dynamically inserted into the razor component, but somehow this seemed easier. Cookie or local storage interop requires JS. This is a very simple bit of code to write, and I would strongly recommend implementing it yourself to become familiar with Blazor component lifecycle events (i.e. how you make sure this JS shim is loaded into DOM before invoking its methods). I've been wanting to create a public GitHub repo with a more practical Blazor boilerplate app that might help others get started with this kind of concern a lot faster. Perhaps something like an LDAP-authenticated business operations dashboard. Seeing an actual cookie session token read/written and how all of the code flows for session management purposes can save days of frustration. I already see some options out there for Nugets that claim to handle Blazor session management for you, but in my experience these almost always get in the way and force techniques upon you that you really didn't want to work with. If you find yourself reading the documentation for a CookiePolicyOptions or ClaimsPrincipal type, you probably went too far down the rabbit hole.
- pknopf 7y ago
  Blazor will only work on an Electron-ish setup. You'll never see adoption on the interwebs. It reminds me of the ole UpdatePanel/AjaxControlToolkit/ViewState world where big/complicated/bloated frameworks with big runtimes were trying to solve super simple problems.
  - okareaman 7y ago
    I thought that too after my initial look at Blazor. Then I realized a big target for Blazor is enterprise and corporate intranets where network speed is many times not the issue
- ryanthedev 7y ago
  .net core in general has grown, building cross platform scalable apps is a breeze. Also they have really built some great performance libs, (Channels, Pipelines, Span, Memory). The tooling is a little wonky at times when it comes to blazor. Hopefully they will turn this into a flagship product.
cryptozeus 7y ago
MS also have their own take on WebAssembly https://dotnet.microsoft.com/apps/aspnet/web-apps/blazor https://dotnet.microsoft.com/apps/aspnet/web-apps/blazor
- resoluteteeth 7y ago
  That's something different. Blazor compiles c# to webassembly to run in the browser. This software (Wasmtime) allows you to run webassembly code from within .net.
  - giancarlostoro 7y ago
    So in theory you could run Blazor on Wasmtime?
    - bob1029 7y ago
      You might as well skip the middle man and use server-side blazor.
    - cptskippy 7y ago
      Yes and that's like going out the front door and coming in the back door to go from the Kitchen to the Den.
      - giancarlostoro 7y ago
        I'm not advocating anybody do that, but it's a fun experiment to think about. I've been intrigued about WebAssembly more than ever when I read a comment here on HN that the specs very generic allowing it to be used even outside the web.
        anon73044 7y ago
        I'll take a WebAssembly desktop app over an Electron desktop app any day of the week
syrusakbary 7y ago
Great work on the article and extension Peter! I didn’t see any reference to existing work in this area in the article, I’m curious to know how this differs from projects like WasmerSharp by Miguel de Icaza released a few months ago. https://github.com/migueldeicaza/WasmerSharp https://github.com/migueldeicaza/WasmerSharp
- sanxiyn 7y ago
  One obvious difference is that WasmerSharp wraps Wasmer. Wasmer and Wasmtime are different.
shahink015 7y ago
certified ethical hackers for hire : https://www.hackerslist.co/ https://www.hackerslist.co/
Nelkins 7y ago
For anyone curious, the actual .NET Wasmtime package source is here: https://github.com/bytecodealliance/wasmtime/tree/master/crates/misc/dotnet https://github.com/bytecodealliance/wasmtime/tree/master/cra...
jonny383 7y ago
Please don't pollute the web with .NET on the client side too. Do we _really_ need this?
- userbinator 7y ago
  MS has had ".NET on the client side" for quite a while now. It's called Silverlight.
  - jonny383 7y ago
    Silverlight was deprecated.
    - pjmlp 7y ago
      Kind of, https://platform.uno/silverlight/ https://platform.uno/silverlight/
- Mountain_Skies 7y ago
  JavaScript has been polluting the server side for quite some time now. Blowback was inevitable.

246 points by skellertor 7y ago

I know MSFT technologies get a lot of hate here, but ASP.NET Core is pretty awesome. Blazor (the wasm based framework) is innovative and a positive step forward frontend web development. You should leave your prejudices aside and give it a try if you haven't yet.

sergiotapia 7y ago
dotnet core is an insanely good sell for any company. seriously take a look at what you can do and forget what you knew about .net of the 2010s.
kirse 7y ago
I really like the approach of Blazor wrt WASM, but really dislike having to dump whole code blocks into CSHTML files like I'm writing old ASP.NET Forms again. Something just feels off. Is there any way to isolate those code blocks and import them? EDIT: To answer my own question, this appears to be the solution: https://www.telerik.com/blogs/using-a-code-behind-approach-to-blazor-components https://www.telerik.com/blogs/using-a-code-behind-approach-t...
- pjmlp 7y ago
  Well there is Blazor components, unless you mean something else.
- SigmundA 7y ago
  Blazor supports components: https://docs.microsoft.com/en-us/aspnet/core/blazor/components?view=aspnetcore-3.1 https://docs.microsoft.com/en-us/aspnet/core/blazor/componen...
- angrysaki 7y ago
  ASP.NET Core 3.1 added support for partial classes for Razor Components, so I don't think you need to use the inheritance style code behind anymore. https://gunnarpeipman.com/blazor-partial-page-class/ https://gunnarpeipman.com/blazor-partial-page-class/
- bob1029 7y ago
  This is something that hosed me up too at first when using Blazor. There is a specific item type in the VS "Add New Item" dialog that is called "Razor Component" with a fancy purple icon next to it. If your files in the solution explorer end in .razor, you are using the correct item type. If your files end in .cshtml, you are going to have a bad time and everything will seem very wrong. At first, I was using the "Add->Razor Page" context menu option assuming this was what I wanted, but it will give you the wrong type of item.
- manigandham 7y ago
  The latest release (.Net 3.1) finished the partial classes implementation so now you can create a `Comp.razor` template file and a separate `Comp.razor.cs` code-behind file that only contains the code. These are automatically compiled together on build.
loudmax 7y ago
> I know MSFT technologies get a lot of hate here Are you reading the same HN as I do? In the last couple of years, I see a lot more positive than negative comments whenever Microsoft comes up. From what I see, Google is the company that gets the most hate on HN. Of course, Microsoft isn't universally loved. There are a lot of people that don't trust them based on their past behavior, and the fact that Windows and Microsoft Office are still an entrenched monopoly. That might not apply to ASP.NET Core, but not everyone is going to let MSFT off the hook.
- saagarjha 7y ago
  Interestingly, I ran some very rough sentiment analysis of the comments here and it turns out that Apple gets people the most worked up, followed closely by Facebook. Of Apple, Google, Microsoft, Amazon, and Facebook, posts about Microsoft did seem to have the most positive comments.
  - somedangedname 7y ago
    To add to the general din: Apple are the worst. They kept me waiting four months this year for a client's enterprise developer enrolment to complete. When the client were enrolled? Surprise! You can't sign apps for in-house distribution for another two weeks. Not mentioned anywhere when you sign up. I talked to Apple support and they told me to pound sand. My last enquiry to Tim Cook's customer complaints inbox went unanswered.
    - saagarjha 7y ago
      Oh, I remember being hit by this. Agree that it's not well documented; I think it's there to prevent "signing services" from spring up (not that it does a great job…)
  - ksec 7y ago
    I thought it was pretty clear even without any Stats. People know what Microsoft is doing, the good things and Open Sources. They dont use it not because of hate, I think it is 1. It isn't good enough to make the jump into another ecosystem or language yet. 2. Not hating doesn't mean loving them. IE era, that is IE 5 - 6 if you aren't old enough ( Yes, some people still bash WebKit as the new IE and thinks IE era meant IE7... ) along with the pain on early Windows days still hurt a bit, they will have to try harder, and doing so continuously to win those people back. The thing about Apple isn't hate as in Google or Facebook. It is people have high expectations of Apple and demands quality from them, and when they are not up to that high bar, people complain.
hackinthebochs 7y ago
Since you seem to have a positive sentiment towards Blazor, can you point me to a good introduction that demonstrates the power and the benefits of the framework, e.g. increased expressiveness, reduced friction, etc? I've looked through a couple of intros but they never seemed to really sell the benefits of it. As someone who loves the C# language and .NET ecosystem I really want to like it but nothing has clicked so far.
- nwah1 7y ago
  The idea is to unify the development process and tooling on the front-end and the back-end, without suffering from poor performance and constant unnecessary roundtrips over the network. Not to mention, a significant number of people strongly prefer C# to Javascript (and even Typescript). If those two things never bothered you, then you might not understand the benefit, and you can continue to use what you like. In practice, sending the .NET libraries over the network is the major burden of the approach Blazor takes, since the first load will be slow and bandwidth-intensive, even though everything will likely be cached for subsequent visits. However, as the WASM tooling and standards improve, the library sizes will shrink, and less libraries in general will be necessary to accomplish stuff that has been solved at the level of web standards.
  - wvenable 7y ago
    There is also server-side Blazor which doesn't use WASM components but instead uses SignalR to do client/server communication. Both are compatible with the same code base (and components). Server-side Blazor still has overhead but it's different from having to send the .NET libraries over the network.
- Gene_Parmesan 7y ago
  Attended a Blazor session at MS Build in May. My impression was, Blazor seems like a super cool tool that I will never be able to justify in production. For one, the performance is poor right now. Your options are either to use Signal to send every action over the network, or to deliver the entire .NET libraries along with the page. The size of that download is both impressively small (given the volume of code you're transferring), and also still way too large for me to feel comfortable foisting that on users. Additionally, it requires that your front-end team feels comfortable working in .NET technologies. Ours certainly doesn't, and it would be very hard to sell my director on anything that doesn't maintain the traditional backend/frontend split.
ailideex 7y ago
> I know MSFT technologies get a lot of hate here, but ASP.NET Core is pretty awesome. Given how bad an actor they were I guess some people have a hard time forgetting the past.
- teh_klev 7y ago
  Sure, but on posts where the comments head downhill lubricated by this trope, often the commentators were still in kindergarten during this time. There's a cargo-cult mentality when it comes to accusing M$ of Embrace, Extend and Extinguish. Sure it happened but the folks leaving these comments weren't around at the time working as pro-software developers. I was, it was annoying, but the world didn't implode, and the law kicked in and did mostly its job. So big deal and yawn. MS has a new management, it was "infiltrated" by the right folks in the early to mid 2000's who educated MS from inside and began to set MS on the right track. It takes time, like steering an oil tanker. But MS are a capitalist corporation, just like all the others, they will all do some evil at some point in time on behalf of their bottom line and shareholder dividends, if they think they can get away with it.
hudo 7y ago
Its actually Win10 that people hate, dev tools are just fine
Mountain_Skies 7y ago
Blazor might pull me back into software development. About five years ago after close to three decades of doing software development, I got tired of seeing so much software being bent and shoved into JavaScript. I absolutely loathe JavaScript so it seemed like a good time to move on to something else, which in my case was IT security. Occasionally I write a tool or two for use by my team but most developer jobs these days require coding in JavaScript so I hadn't given much thought to going back to full time development work. Blazor however has been a joy to work with. My understanding is JavaScript will still be required for a while on most webassembly apps but for my uses I've been able to avoid doing any directly. Maybe in another couple of years the market will change and those who don't want to use JavaScript everywhere and are horrified that even embedded systems are flirting with js, will again have a place in the world.
- bob1029 7y ago
  I have found similar joys in using Blazor. Once you get past the boilerplate stage, the productivity gains go exponential very quickly. Component reuse + strong typing + no API controllers or JSON contracts = how web development should have always been. I've got elegant LINQ statements right in my component markup. Creating extremely complex tables and views is so trivial with this combination of technologies. I can even subscribe my razor components to CLR events and everything works exactly the way you'd hope it would. The SignalR link between client and server abstracts away a huge bucket of questionable practices, with some potential trade-offs. Perhaps there is some downside I haven't found yet, but at this point I feel I could live with whatever strangeness might begin to emerge from the path I have taken. In my experience, it is not possible to completely eliminate JS from the equation with Blazor. I've had to write a single .js file which I currently use for 3 things: Reading a cookie, writing a cookie and focusing an arbitrary DOM element. The focus concern I could probably alternatively handle with an autofocus attr which is dynamically inserted into the razor component, but somehow this seemed easier. Cookie or local storage interop requires JS. This is a very simple bit of code to write, and I would strongly recommend implementing it yourself to become familiar with Blazor component lifecycle events (i.e. how you make sure this JS shim is loaded into DOM before invoking its methods). I've been wanting to create a public GitHub repo with a more practical Blazor boilerplate app that might help others get started with this kind of concern a lot faster. Perhaps something like an LDAP-authenticated business operations dashboard. Seeing an actual cookie session token read/written and how all of the code flows for session management purposes can save days of frustration. I already see some options out there for Nugets that claim to handle Blazor session management for you, but in my experience these almost always get in the way and force techniques upon you that you really didn't want to work with. If you find yourself reading the documentation for a CookiePolicyOptions or ClaimsPrincipal type, you probably went too far down the rabbit hole.
pknopf 7y ago
Blazor will only work on an Electron-ish setup. You'll never see adoption on the interwebs. It reminds me of the ole UpdatePanel/AjaxControlToolkit/ViewState world where big/complicated/bloated frameworks with big runtimes were trying to solve super simple problems.
- okareaman 7y ago
  I thought that too after my initial look at Blazor. Then I realized a big target for Blazor is enterprise and corporate intranets where network speed is many times not the issue
ryanthedev 7y ago
.net core in general has grown, building cross platform scalable apps is a breeze. Also they have really built some great performance libs, (Channels, Pipelines, Span, Memory). The tooling is a little wonky at times when it comes to blazor. Hopefully they will turn this into a flagship product.

cryptozeus 7y ago

MS also have their own take on WebAssembly https://dotnet.microsoft.com/apps/aspnet/web-apps/blazor https://dotnet.microsoft.com/apps/aspnet/web-apps/blazor

resoluteteeth 7y ago
That's something different. Blazor compiles c# to webassembly to run in the browser. This software (Wasmtime) allows you to run webassembly code from within .net.
- giancarlostoro 7y ago
  So in theory you could run Blazor on Wasmtime?
  - bob1029 7y ago
    You might as well skip the middle man and use server-side blazor.
  - cptskippy 7y ago
    Yes and that's like going out the front door and coming in the back door to go from the Kitchen to the Den.
    - giancarlostoro 7y ago
      I'm not advocating anybody do that, but it's a fun experiment to think about. I've been intrigued about WebAssembly more than ever when I read a comment here on HN that the specs very generic allowing it to be used even outside the web.
      - anon73044 7y ago
        I'll take a WebAssembly desktop app over an Electron desktop app any day of the week

syrusakbary 7y ago

Great work on the article and extension Peter! I didn’t see any reference to existing work in this area in the article, I’m curious to know how this differs from projects like WasmerSharp by Miguel de Icaza released a few months ago. https://github.com/migueldeicaza/WasmerSharp https://github.com/migueldeicaza/WasmerSharp

sanxiyn 7y ago
One obvious difference is that WasmerSharp wraps Wasmer. Wasmer and Wasmtime are different.

shahink015 7y ago

certified ethical hackers for hire : https://www.hackerslist.co/ https://www.hackerslist.co/

Nelkins 7y ago

For anyone curious, the actual .NET Wasmtime package source is here: https://github.com/bytecodealliance/wasmtime/tree/master/crates/misc/dotnet https://github.com/bytecodealliance/wasmtime/tree/master/cra...

jonny383 7y ago

Please don't pollute the web with .NET on the client side too. Do we _really_ need this?

userbinator 7y ago
MS has had ".NET on the client side" for quite a while now. It's called Silverlight.
- jonny383 7y ago
  Silverlight was deprecated.
  - pjmlp 7y ago
    Kind of, https://platform.uno/silverlight/ https://platform.uno/silverlight/
Mountain_Skies 7y ago
JavaScript has been polluting the server side for quite some time now. Blowback was inevitable.