I have recently started learning ASP.NET Core with the help of an ebook. There are few statements mentioned in the initial chapters, which I am unable to understand clearly.
For eg. following statements are mentioned under Foundational improvements in ASP.NET Core section
Lightweight and modular HTTP request pipeline
Ships entirely as NuGet packages including the runtime
Runtime can be installed Side-by-side- allows you to version application along with runime
The above statements are not clear to me probably because of the term "modular HTTP request pipeline" from Point 1 and terms "runtime" and "version application" from Point 2.
Any short explanation or reference to the suitable doc will be appreciated.
Thanks
http request pipeline
They totally rebuild the HttpListener which is also called the http server. Normally you would host your application in iis which would give you tons of functions but is 1 very old, massive sluggish application.
Now on default you run the application as a console which starts up a HttpListener which is called Kestrel in dotnet core.
This kestrel is totally build from the ground up (so modular priciples and barely any technical depth). And is build based on a very vast C++ library called libuv.
The modularity in this means that it has been build in various loosly coupled parts, meaning that you could replace or extend those parts if you want to. For example use a test server for automatic integration tests.
Ships in nuget packages
Normally you would install a netFramework eg: 4.5.0 and you would already get all these system.* dlls eg: System.web.dll
Now all these dll's are nuget packages and bundled into 1 package called netstandard: https://www.nuget.org/packages/NETStandard.Library/.
Multiple runtimes
If you build a dotnet project, it creates Dlls. these dlls can be run by by any OS if that os has installed the dotnet runtime. (basicaly dll is intermediate language and can be run by the dotnet runtime).
You can also build your dotnet project to include the runtime inside your application, so you can run multiple dotnet applications on an OS with different Dotnet runtime versions.
The downside of this last option is that you have to build your dotnet project for every OS specifically. So normally people choose to just build the OS independent Dlls and make sure the right runtime is installed on the OS.
Related
Can anyone help as to how to use the run time binaries found in the link below?
https://www.microsoft.com/net/download/windows
Basically, we are moving to .NET Core (we have been using .NET framework 4.0 for many years - so big shift as you can guess). I am kind of nervous to install .NET core on the production server (Windows Server 2012). Is it safe to install .NET Core on a server running .NET framework 4.0? If no, is there any way I can get the .NET Core runtime on to the server without installing them (kind of copying portal libraries) so that I can start with the beta testing of the app. Any help would be much appreciated. Thanks!
EDIT:
It is not duplicate, One of the main questions I had if I can use portable binaries on the server to run my app, without actually installing them (got the answer below, thanks again). Not sure someone down voted this without any reason. It makes the developers nervous to ask a question in StackOverflow. if they can mention the reason that would be great!
There are no issues when installing .NET Core and .NET Framework on the same machine. They are designed to allow them to be installed side-by-side.
However you do need to install the .NET Core runtime onto the server to allow the code to be run because the OS has native dependencies that need to be present. See this link for more information.
With .NET Core you can do framework dependent deployments (FDD) and self-contained deployments (SCD). FDD requires any shared assemblies to be present on the server i.e. System.* assemblies etc. but an SCD only requires the basic runtime/native dependencies. For an SCD your app deployment would include any .NET Core shared assemblies in it's deployment package.
You can read more about FDD and SCD here
Also there is more information about the native dependencies on different OS platforms here
I'd like to (try to) add HTTP/2 support to Kestrel - for my own edification, for now. I'm using Ubuntu as my dev platform, because my requirements include using Linux.
Of course, it appears fairly simple to make changes to the Kestrel code - just clone the source from https://github.com/aspnet/KestrelHttpServer, then make my changes, then build the assembly. The problem I'm having, is getting other code to reference my modified code/assembly rather than the "official" assembly from .NET Core. To that end, I would love to hear how to do the following:
"Install" my changed Kestrel assembly locally such that anything that depends on that assembly uses my changes automatically. This may include projects that I create via dotnet new -t web, as well as other .NET Core assemblies that I haven't modified.
Be able to propagate my changes to other machines as necessary, in a controlled manner.
Thank you, and have a good one!
There are 2 options
create own nuget package from sources using dotnet pack command, and then use own feed for nuget restore. See related SO answer and Hosting your own nuget feed guide;
or
add Kestrel project into your solution and add dependency as "project reference".
When I use a Visual Studio 2015 template to create a brand-new ASP.NET Core project, I see a couple of unexpected pieces. I'd like to understand these:
By default, the new project targets dnxcore50 and dnx451. I thought ASP.NET 5 / MVC 6 required .net 4.6, so I don't know why dnx451 is one of the default targets.
Regardless of dnx target, the startup.cs file specifies app.UseIISPlatformHandler. I've been running the dnxcore50 target in Docker (i.e. Linux) without any problem, even though Linux does not have IIS. So I don't know what UseIISPlatformHandler does. I can find no documentation for it either.
Can anyone clarify?
Why dnx451 instead of dnx46 is basically IIS's fault, see answer here. Also perhaps the templates run behind because Azure has not yet switched to 4.6? Just a little theory of mine. I'm not sure.
UseIISPatformHandler is again only used for IIS. You can savely remove it if you have no interest in publishing your web app to IIS. You can learn more about the HTTP Platform Handler (which IIS needs) here. And you can learn more about the IIS Platform Handler Middleware from the source code.
Does this make it more clear?
I have create a sample ASP.NET 5 application (pretty much the example one from New Solution), and pushed it to GIT hosted on Visual Studio Team Services (former Visual Studio Online). I want to set up continuous integration to Azure Web App (former Azure Web Site). I have tried to set it up from Azure portal itself, it did create a new build definition, but it fails to build ASP.NET 5. I have found a guide how to do this, but it never really worked for me, I get errors like this e.g.
Error parsing solution file at C:\a\1\s\Frontend\src\Frontend\Frontend.xproj: Exception has been thrown by the target of an invocation.
Predefined type 'System.Void' is not defined or imported
Another problem is that it seems it really takes a lot of time to install dnvm, get packages, etc. So all in all it's a pain to make it work.
So are there real alternatives for that or more importantly is Microsoft is planning to implement something like a Build ASP.NET 5, Deploy ASP.NET to Azure and such to make it easy as I suppose it's easy with the current ASP.NET 4 apps. I really hope that it will be an option soon since it's quite impossible to work with current build system.
For "System.Void" issue, please check the runtime version in "global.json" file and make sure it is consistent with the dependencies in "project.json" file.
For dnvm install issue, since AspNet5 runtime environment isn't installed on VSTS Hosted Build Agent for now and the different users may use different runtime versions, it requires the user to add a "PreBuild" PowerShell step to read the runtime version in "global.json" file and then install it. If you can make sure that you will always only use one version (For example: 1.0.0-rc1-update1), you can deploy your own build agent and install "1.0.0-rc1-update1" on it, then you can skip the dnvm installation during the build process.
Take a look on http://riffer.eu/wordpress/?p=112. There I have a solution vor asp.net core RC_1.
Amazingly you need only two powershell scripts - there is no compiling / visual studio necessary.
What's the story going to be (if any) around interop with unmanaged code for ASP.net vNext / Core CLR?
The key bits (DllImport and friends) appear to be present to allow for unmanaged code interop, but how would things such as packaging and deployment work in this context? The basic build artifact in vNext / CoreFX no longer appears to be an assembly, but a NuGet package. So in that case, how would we make the new project.json system work so that unmanaged dlls that we're P/Invoking into are also included in the resulting NuGet package?
Or am I talking about scenarios that have not been considered yet (or more disappointingly, not going to happen)?
The story is yet to be fully fleshed out, but there are already examples of how to do this. Ultimately we (the Microsoft teams working on this) are working on some scenarios to enable NuGet packages to better support native content in packages.
To see one example of this, the Kestrel web server has some of its own managed code, plus it includes libuv in its NuGet package for an efficient async IO implementation that is cross-platform.
Because there isn't yet a built-in general solution in NuGet, the build scripts for Kestrel use some custom actions to include the native content in the NuGet package. Then to load libuv there's some code that dynamically figures out which native libuv to load based on the environment in which it is running.
So, yeah, it's a bit messy, but it does work, and this is definitely high on the team's priority list to improve.