Can't run .Net Core based on project.json after VS 2017 installation - asp.net-core

I've been working on a software for a while and always executed it using dotnet run. Today, I decided to install VS 2017 and after that (still not entirely sure if it's the root cause, though), I can't run my software anymore.
The pre-existing project is nowhere near the project I opened with VS 2017 so the only collision I suspect might be due to the Core version being changed. To be sure, I re-ran the installation from the page, the latest version.
dotnet --version
1.0.0-preview4-004233
I notice that when I execute dotnet new, the directory get a xxx.csproj file and not project.json and I've read somewhere that MS is going to drop support for it.
What can I do to get the pre-existing project running again? I'm kind of stuck in the middle of the whole thing and googling gave me precisely nothing. Apparently, I'm the first dude to do this stupid upgrade (if it's because of that to begin with).

What can I do to get the pre-existing project running again?
Add a global.json to your project or solution's root directory, with an SDK property that points at the previous SDK. For example:
{
"sdk": {
"version": "1.0.0-preview2-003131"
}
}
View the SDK versions that you have installed like this:
PS> dir 'C:\Program Files\dotnet\sdk\' -name
1.0.0-preview2-003131
1.0.0-preview2-003133
1.0.0-preview2-003156
1.0.0-preview2-1-003177
1.0.0-preview3-004056
Anything with preview2 will use project.json, anything with preview3 (or above) will use xxx.csproj.
See also: Announcing .NET Core Tools MSBuild “alpha” > Side by side install.

Related

dotnet build - working, dotnet publish - not working

I try publish ASP .NET Core2 app.
App is work in visual studio 2017
dotnet build -c Release completed without error
dotnet publish -c Release
Has error
Cannot find compilation library location for package 'Hangfire.MemoryStorage'
But Hangfire.MemoryStorage is _Libs\Hangfire.MemoryStorage.dll not a package
build compiles all your .cs files mainly
publish also compiles all your view files into a single .dll file. So it validates your views as well.
So, If you have an error only in the publish and not in the build, there most probably must be a bug somewhere in your views. Even if the app worked in visual studio, there might be a run time issue somewhere if the bug is in a view.
Regarding the Hangfire.MemoryStorage library. The last update was three months ago. There have also been past issues with this library related to the code not updated for the latest version of .net core. So, I don't think he has released the stable version for .net core 2.0 yet (assuming you have the latest version of the app installed).

System could not be found Visual Studio 2017 ASP.NET Core project

I've installed the newly released version of Visual Studio 2017 and started a fresh ASP.NET Core project targeting .NET Core.
Out of the box, I'm getting the
The type or namespace name 'System' could not be found (are you
missing a using directive or an assembly reference?)
error. Any idea what's causing this and how to fix it?
Also, looks like there are problems with NuGet packages as well:
I also tried dotnet restore on the project through the command line and got the following error:
P.S. Kind of disheartening that you get an error in a fresh new project in the latest version of Visual Studio 2017!
UPDATE:
SDK version is v 1.0.1 -- see below:
UPDATE 2:
This is very strange. Looks like the original problem was due to NuGet package source pointing to a folder under Visual Studio 2015 folder. I unchecked it and left only nuget.org. With that my project seemed to have restored all the packages and when I started the project it loads up the standard ASP.NET page. But if I open startup.cs file, I get red squigglies all over the place but if I run the project, it works fine. What's going on here?
UPDATE 3:
I closed the project and VS 2017. I then restarted VS 2017 and opened the project and now it seems to be fine. And I'm not referencing the .NETStandard library 1.6.1 and everything seems to be working fine now.
I had the same issue in my Visual studio 2017 .Net Core application. I closed the Visual studio and re-open fixed everything.
Came across the same issue today. I had an old nuget source that no longer existed. So I went into Tools > Nuget Packet Manager and un-checked the wrong one. Hit "Ok", and then rebuilt the project, and it works great now. It seems like you stumbled onto it, but also wanted to verify that it fixed my issue, and it does.
I had the same problem, first when converting a VS2015 net core mvc web project to 2017 and then when trying to create a new core web application in 2017.
Went to Tools|NuGet Package Manager|Package Manager Settings - checked 'Allow NuGet to download missing packages' and 'Automatically check for missing packages during build in VS' and then clicked 'Clear All NuGet Cache(s)'.
Then re-built the solution - it found and loaded all the required packages and ran OK.
May not work for all cases but simple and worth a try.
Multiple closing and reopening of VS2017 fixed it for me.
I had the same issue, the solution for me was to clear the NuGet cache. Tools > NuGet Package Manager > Package Manager Settings > Clear All NuGet Cache(s)
Check the version .NET Command Line Tools in CMD, just type dotnet --info. If version is 1.0.0, then try to install latest version .NET Core SDK from here.
Find the broken project and right click, Unload, right click, Re-load. Fastest fix for me.
If you get the problem while using the CLI, try doing nuget restore instead of dotnet restore as that sometimes pulls down packages that the dotnet CLI seems to miss.
I have had the same issue with Visual Studio 2019 and .NET Core SDK 2.2.
These steps solved the problem:
Close the Visual Studio
Open the Visual Studio as Administrator
Open the Solution
Right click on Solution -> Restore NuGet Packages
I've tried all answers above. For me works only removal and adding the reference again described in the following steps:
Open 'References' under the project.
Right click on 'System' reference.
Click on 'Remove'.
Right click on 'References'.
Click 'Add Reference...'.
From right menu choose an 'Assemblies',
In a search field type 'System'.
Choose 'System' from the list.
Click 'Add' button.
IMPORTANT: Restart the Visual Studio.
'System' reference you can replace with any you need.
Try adding the following line above the other references in the csproj file
<Reference Include="netstandard" />
For me the problem was caused by my project having a custom IntermediateOutputPath. For some reason, if project_name.csproj.nuget.g.targets is not in obj subfolder of project folder, the error occurs.
Using default IntermediateOutputPath or keeping a shadow copy of project_name.csproj.nuget.g.targets in fake obj folder solves the problem for me.
This issue seems to be triggered by a myriad of reasons. Mine was caused by cloning directly from VSTS using Git Bash, my project directory had spaces in it. Git Bash changed those spaces in the path to %20. It was throwing off all the references in my project. So for anyone who tried everything else and are at their wits end, make sure %20 is not in the path.
So, I have cloned the repository from github and started getting this error.
It was my project uploaded from another machine. I later realized that I have used the materialdesign packages in my project.
I have uninstalled and reinstalled these packages and it fixed my issue.
Had the same problem. Uninstalled Application Insights from my projects using the nuget package manager. I'm not looking at that yet, I just wanted core and unit tests. Problem solved.
I also had the same problem.
The is no SDK folder under the Dependencies one. Therefore, no Microsoft.NetCore.App libraries !
To solve this problem, in Nuget manager window, install any nuget which depends on .NetCoreApp (you can install for example Microsoft.AspNetCore or BundlerMinifier.Core from the Microsoft Visual Studio Offline Packages source).
The SDK will be restored by the same time.
Once it is back, you can uninstall the previously added nuget. The SDK will remain in place.
Not quite sure in which order vs 2017 trying to resolve packages.
But my situation was following. In my VS2015 I had configured local and 3rd party source for nuget packages, newly installed version of 2017 loaded them too.
https://api.nuget.org/v3/index.json was first in list.
But vs2017 throwed an error that it can't restore .net core libraries from my another local repo.
After I unchecked all of them except https://api.nuget.org/v3/index.json, it had started to working normally.
I had this problem too, but not right now, this steps solved my problem: Choose Project -> Properties from the menu bar. In the Project properties window, under Configuration Properties -> General, make sure that Common Language Runtime Support is set to Common Language Runtime Support (/clr)
Simply opening the NuGet package manager and then the Visual Studio settings related to it - without changing anything - merely looking around, and when I closed out, the problem was gone.
This seems to be an intermittent issue that can come and go for no obvious reason.
None of the answers here worked for me so I'm posting what did work.
My errors were mostly the same as the original poster but I also had:
Error loading meta data for 'Microsoft.Extensions.FileProviders.Embedded.2.0.1'
hexadecimal value 0x1C invalid character
Every time I attempted to download a different nuget package or restore old packages I would see this error. I also saw the other errors such as:
type or namespace system could not be found
What worked for me:
opened the filepath that the error said the bad metadata was in, which for me was C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.extensions.fileproviders.embedded\2.0.1
Then, I put the contents of that folder into another folder I named "hiding".
Then, I went back to the nuget package manager and tried to install a package, hoping to have the SDK restored. IOt worked successfully, and all my other errors were gone as well, and the fresh new project runs as it should!
The problem for me occurred when running my Visual Studio as Admin with a separate user-- I had created a Git Repo with the source files in the user documents of my normal account. When I created a new solution in that folder the above errors occurred. Try creating your project in a different place and see if the error still occurs.
I was facing the same issue when I created a new project (.net Core 2.2) in VS2019.In my case there was an Azure package which was creating the problem.I uninstalled it and the project started working fine.
Run mentioned below command to uninstall the package.
Uninstall-Package Microsoft.VisualStudio.Azure.Containers.Tools.Targets -Version 1.7.10
I had the same problem. I cloned a github project and this error came. So I deleted the cloned project and then I cloned the project again and it worked fine.

ASP.Net Core 1.1 - Migration Failure

I know VS 2017 is only RC but there seem to be some major issues with migrating an ASP.Net Core 1.0 project to 1.1. The migration tool fails converting 2 of my 8 projects in the solution (I prefer to adopt a layered architectural approach for my projects) the sample project is located here. One project in particular is the class library I moved my web api controller methods into. In trying to re-create this class library it doesn't seem one is able to declare a controller class after installing Microsoft.AspNetCore.Mvc nuget. It is installed but the compiler is not finding the Controller, RouteAttribute classes, etc. The same issue occured with trying to setup a DI layer IServiceCollection. Nuget Microsoft.Extensions.DependencyInjection doesn't seem to be doing it.
The migration log quite honestly isn't really helping me. It seems to indicate an issue with my service project and the project.json file but as you can tell it is in the repository.
It feels like Microsoft is forcing us down the path of cramming all the "web" stuff into a single project file. Maybe these tools aren't far enough along yet but an RC would indicate they should be closer to ship ready?
ReciPiBook.Api
Message
src\ReciPiBook.Api\ReciPiBook.Api.xproj: Failed to migrate XProj project ReciPiBook.Api. 'dotnet migrate -s -p "C:\Users\xxx\Documents\Visual Studio 2015\Projects\ReciPiBook2017\ReciPiBookCore\src\ReciPiBook.Api" -x "C:\Users\xxx\Documents\Visual Studio 2015\Projects\ReciPiBook2017\ReciPiBookCore\src\ReciPiBook.Api\ReciPiBook.Api.xproj"' exited with error code 1.
src\ReciPiBook.Api\ReciPiBook.Api.xproj: Could not find file 'C:\Users\xxx\Documents\Visual Studio 2015\Projects\ReciPiBook2017\ReciPiBookCore\src\ReciPiBook.Services\project.json'. Migration failed.
src\ReciPiBook.Api\ReciPiBook.Api.xproj: Backing up C:\Users\xxx\Documents\Visual Studio 2015\Projects\ReciPiBook2017\ReciPiBookCore\src\ReciPiBook.Api\ReciPiBook.Api.xproj to C:\Users\xxx\Documents\Visual Studio 2015\Projects\ReciPiBook2017\ReciPiBookCore\Backup\src\ReciPiBook.Api\ReciPiBook.Api.xproj.
src\ReciPiBook.Api\project.json: Backing up C:\Users\xxx\Documents\Visual Studio 2015\Projects\ReciPiBook2017\ReciPiBookCore\src\ReciPiBook.Api\project.json to C:\Users\xxx\Documents\Visual Studio 2015\Projects\ReciPiBook2017\ReciPiBookCore\Backup\src\ReciPiBook.Api\project.json.
I can't directly speak to VS2017 as I'm staying away from it as even though it's a RC, the core tooling is in ALPHA. The VS 2015 core tooling is at least in a "RC" state (actually only preview).
In VS2015 I migrated from 1.0.x to 1.1 manually (per https://blogs.msdn.microsoft.com/dotnet/2016/11/16/announcing-net-core-1-1/):
Download the 1.1 sdk
Change your global.json "sdk":{"version": "1.0.0-preview2-1-003177"} (yes it's a different version string).
Update all the project.json package versions from 1.0 to 1.1 (some are preview some arn't). Just open up the nuget package manager, allow preview versions, then install all the updates.
Fix any of your project.json tool entries as the package manager clobbers those.

How can I debug the source code of .Net Core or the Base class libraries (coreFx)?

I am using .NET Core 1.0 and Visual Studio 2015 Update 3 to make a simple Asp.Net Core MVC website.
How can I debug my application and "Step Into" the .NET Core source code that is available on GitHub?
Specifically, I am trying to troubleshoot one issue with Microsoft.AspNetCore.Authentication.Facebook 1.0.0 assembly that I fetched from NuGet.
I wrote this article more than 1 year ago so it's a bit out of date but the idea is still the same:
You sync to the correct tag from GitHub. In your case, you probably want to sync to tag 1.0.0
Build that repository by running build.cmd or build.sh
Add the src folder path to your app's global.json file. For example, if you cloned Security in D:\Security, then you add D:/Security/src to global.json in the projects property.
Rebuild everything and it should work.
PS: If you use VS and don't see immediately the new code, try restarting it. It's a known issue that sometimes it doesn't pick up the changes to global.json
Update to fit new VS 2017
In Visual Studio 2017 15.3.5 and later
We can use SourceLink support for debugging .NET Core and ASP.NET Core sources.
To enable source link support just Disable Enable Just My Code and and Enable Enable Source Link Support.
Then Enable Microsoft symbol servers.
Victors answers works well with vs 2015.For some one who is looking for a solution with vs 2017,
In vs 2017 there is no global.json availble.So instead of adding folder path in global.json a project reference has to be added and rebuild.
All the others mentioned in Victors article works same as with 2015.
It is important that the git hub tag and the nuget package matches have the same versions.
Also make sure that on a solution level, you have your project "configration", set to debug. See screenshot. .
.
(For the solution properties to show up, right click on the .sln in the solution explorer.)
If you have debugged an app before with the previous version of .NET, delete the %TEMP%/SymbolCache directory as it can have old PDBs that are out of date. Per Debug .NET and ASP.NET Core source code

Make local TFS build agent to use v14 msbuild tools

I've got a couple of ASP.NET vNext applications and I want my CI server to also be able to build them. Both my local machine and the CI server are running VS2015 RC. Then we've got VS Online and a local build controller - which is the server mentioned.
However, I cannot get builds going since it seems to be looking for v12 tooling - which does not include anything DNX.
So - building the solution gives:
The Dnx Runtime package needs to be installed. See output window for
more details
It is installed - since it came with VS2015 RC, AFAIK. So I thought the build template isn't using v14 tooling. I downloaded the Default Git template v12. And indeed it says:
<this:Process.BuildProcessVersion>12.0</this:Process.BuildProcessVersion>
So I switched that to 14, uploaded template, ran build. Then:
Exception Message: The build controller used for this build does not
support the version of the template file used by the build definition.
The version of the template file is 14.0. The maximum supported
version for this build controller is 12.0.0.0.
So trying to solve this - got me to this forum question that states:
Then, instead of changing the BuildProcessVersion property, you need
to change the involved MSBuild version. Open the build process template, find the Run MSBuild for Project activity, change the ToolPath property to the 2013 version msbuild
So - I checked out the template - there is no ToolPath version. There is a ToolVersion property however - which I'll try setting to 14:
In short, my question is: how can I build ASP.NET vNext apps on my build server, that has VS2015RC installed - but is building using v12 tooling?
UPDATE
Seems that the problem is not as much in using the wrong tooling, but more in finding/using the correct DNX runtime while running under a service account ( which the TFS agent is doing ). I've added an issue for the DNX team: https://github.com/aspnet/dnx/issues/2239 .
use msbuild parameter /p:VisualStudioVersion=14.0 ,which can be added in build definition .