This document outlines how to build the source in the aspnetcore
repo locally for development purposes.
For more info on issues related to build infrastructure and ongoing work, see https://github.com/dotnet/aspnetcore/labels/area-infrastructure.
This tutorial assumes that you are familiar with:
- Git
- The basics of forking and contributing to GitHub projects
- Command line fundamentals in your operating system of choice
Development is done in your own repo, not directly against the official dotnet/aspnetcore
repo. To create your own fork, click the Fork button from our GitHub repo as a signed-in user and your own fork will be created.
💡 All other steps below will be against your fork of the aspnetcore repo (e.g.
YOUR_USERNAME/aspnetcore
), not the officialdotnet/aspnetcore
repo.
ASP.NET Core uses git submodules to include the source from a few other projects. In order to pull the sources of the these submodules when cloning the repo, be sure to pass the --recursive
flag to the git clone
command.
git clone --recursive https://github.com/YOUR_USERNAME/aspnetcore
If you've already cloned the aspnetcore
repo without fetching submodule sources, you can fetch them after cloning by running the following command.
git submodule update --init --recursive
💡 Some ISPs have been known to use web filtering software that has caused issues with git repository cloning, if you experience issues cloning this repo please review https://help.github.com/en/github/authenticating-to-github/using-ssh-over-the-https-port.
The first time you clone your repo locally, you'll want to set an additional Git remote back to the official repo so that you can periodically refresh your repo with the latest official changes.
git remote add upstream https://github.com/dotnet/aspnetcore.git
You can verify the upstream
remote has been set correctly.
git remote -v
> origin https://github.com/YOUR_USERNAME/aspnetcore (fetch)
> origin https://github.com/YOUR_USERNAME/aspnetcore (push)
> upstream https://github.com/dotnet/aspnetcore.git (fetch)
> upstream https://github.com/dotnet/aspnetcore.git (push)
Once configured, the easiest way to keep your repository current with the upstream repository is using GitHub's feature to fetch upstream changes.
If you ultimately want to be able to submit a PR back to the project or be able to periodically refresh your main
branch with the latest code changes, you'll want to do all your work on a new branch.
git checkout -b NEW_BRANCH
Developing in the aspnetcore
repo requires some additional tools to build the source code and run integration tests.
Building ASP.NET Core on Windows (10, version 1803 or newer) requires that you have the following tooling installed.
💡 Be sure you have least 10 GB of disk space and a good Internet connection. The build scripts will download several tools and dependencies onto your machine.
Visual Studio 2019 (16.10 Preview 3) is required to build the repo locally. If you don't have visual studio installed you can run eng/scripts/InstallVisualStudio.ps1 to install the exact required dependencies.
💡 By default, the script will install Visual Studio Enterprise Edition, however you can use a different edition by passing the
-Edition
flag. :bulb: To install Visual Studio from the preview channel, you can use the-Channel
flag to set the channel (-Channel Preview
). :bulb: Even if you have installed Visual Studio, we still recommend using this script to install again to avoid errors due to missing components.
./eng/scripts/InstallVisualStudio.ps1 [-Edition {Enterprise|Community|Professional}] [-Channel {Release|Preview}]
💡 To execute the setup script or other PowerShell scripts in the repo, you may need to update the execution policy on your machine. You can do so by running the
Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser
command in PowerShell. For more information on execution policies, you can read the execution policy docs.
The global.json file specifies the minimum requirements needed to build using msbuild
. The eng/scripts/vs.json file provides a description of the components needed to build within VS. If you plan on developing in Visual Studio, you will need to have these components installed.
💡 The
InstallVisualStudio.ps1
script mentioned above reads from thevs.json
file to determine what components to install.
Git on Windows
If you're reading this, you probably already have Git installed to support cloning the repo as outlined in Step 1.
NodeJS on Windows
Building the repo requires version 14.17.6 or newer of Node. You can find installation executables for Node at https://nodejs.org.
Yarn on Windows
NodeJS installs the Node package manager (npm) by default. This repo depends on Yarn, an alternate package manager for the Node ecosystem. You can install Yarn from the command line using the following command.
npm install -g yarn
tar on Windows
Building the repo requires tar to be installed. First, check whether tar.exe
is already in your path i.e. execute tar -help
(Win10 comes with tar already installed). Then, assuming you have git
installed, you might add C:\Program Files\Git\usr\bin\
to your path to pick up the tar.exe
that ships with git
. Finally, you can find installation executables of tar at http://gnuwin32.sourceforge.net/packages/gtar.htm; download that and add the installation directory to your PATH variable.
This repo contains some Java source code that depends on an install of the JDK v11 or newer. The JDK can be installed from either:
- OpenJDK https://jdk.java.net/
- Oracle's JDK https://www.oracle.com/technetwork/java/javase/downloads/index.html
Alternatively, you can run eng/scripts/InstallJdk.ps1 to install a version of the JDK that will only be used in this repo.
./eng/scripts/InstallJdk.ps1
The build should find any JDK 11 or newer installation on the machine as long as the JAVA_HOME
environment variable is set. Typically, your installation will do this automatically. However, if it is not set you can set the environment variable manually:
- Set
JAVA_HOME
toRepoRoot/.tools/jdk/win-x64/
if you used theInstallJdk.ps1
script. - Set
JAVA_HOME
toC:/Program Files/Java/jdk<version>/
if you installed the JDK globally.
This repo contains a Selenium-based tests require a version of Chrome to be installed. Download and install it from https://www.google.com/chrome.
The following extensions are recommended when developing in the ASP.NET Core repository with Visual Studio Code.
If you plan on working with the Windows installers defined in src/Installers/Windows, you will need to install the WiX toolkit from https://wixtoolset.org/releases/.
You can also build ASP.NET Core on macOS or Linux. macOS Sierra or newer is required if you're building on macOS. If you're building on Linux, your machine will need to meet the .NET Core Linux prerequisites.
💡 Be sure you have least 10 GB of disk space and a good Internet connection. The build scripts will download several tools and dependencies onto your machine.
curl
and wget
are command line tools that can be used to download files from an HTTP server. Either utility will need to be installed in order to complete the setup. Typically, these will be included on your machine by default.
If neither utility is installed, you can install curl (https://curl.haxx.se) or wget (https://www.gnu.org/software/wget).
If you've made it this far, you've already got Git
installed. Sit back, relax, and move on to the next requirement.
Building the repo requires version 14.17.6 or newer of Node. You can find installation executables for Node at https://nodejs.org.
NodeJS installs the Node package manager (npm) by default. This repo depends on Yarn, an alternate package manager for the Node ecosystem. You can install Yarn from the command line using the following command.
npm install -g yarn
This repo contains some Java source code that depends on an install of the JDK v11 or newer. The JDK can be installed from either:
- OpenJDK https://jdk.java.net/
- Oracle's JDK https://www.oracle.com/technetwork/java/javase/downloads/index.html
Similar to the instructions above for Windows, be sure that the the JAVA_HOME
environment variable is set to the location of your Java installation.
Before opening our .sln/.slnf files in Visual Studio or VS Code, you will need to at least restore the repo locally.
To set up your project for development on Visual Studio, you'll need to execute the following command. Building subsets of the repo e.g. Java projects may (depending on your scenario) be necessary before building within Visual Studio because those projects are not listed in AspNetCore.sln.
.\restore.cmd
💡 If you happen to be working on macOS or Linux, you can use the
restore.sh
command.
This will download the required tools and restore all projects inside the repository. At that point, you should be able to open the .sln file or one of the project specific .slnf files to work on the projects you care about.
💡 Pro tip: you will also want to run this command after pulling large sets of changes. On the main branch, we regularly update the versions of .NET Core SDK required to build the repo. You will need to restart Visual Studio every time we update the .NET Core SDK.
💡 Rerunning the above command or, perhaps, the quicker
.\build.cmd -noBuildNative -noBuildManaged
may be necessary after switching branches, especially if the$(DefaultNetCoreTargetFramework)
value changes.
Typically, you want to focus on a single project within this large repo. For example,
if you want to work on Blazor WebAssembly, you'll need to launch the solution file for that project by changing into the src/Components
directory and executing startvs.cmd
in that directory like so:
cd src\Components
.\startvs.cmd
After opening the solution in Visual Studio, you can build/rebuild using the controls in Visual Studio.
We have a single .sln file for all of ASP.NET Core, but most people don't work with it directly because Visual Studio doesn't currently handle projects of this scale very well.
Instead, we have many Solution Filter (.slnf) files which include a sub-set of projects. See the Visual Studio documentation here for more information about Solution Filters.
These principles guide how we create and manage .slnf files:
- Solution files are not used by CI or command line build scripts. They are meant for use by developers only.
- Solution files group together projects which are frequently edited at the same time.
- Can't find a solution that has the projects you care about? Feel free to make a PR to add a new .slnf file.
Before opening the project in Visual Studio Code, you will need to make sure that you have built the project. You can find more info on this in the "Building on command-line" section below.
To open specific folder inside Visual studio code, you have to open it with startvscode.cmd
file. Ths will setup neccessary environment variables and will open given directory in Visual Studio Code.
Using Visual Studio Code with this repo requires setting environment variables on command line first. Use these command to launch VS Code with the right settings.
💡 Note that you'll need to launch Visual Studio Code from the command line in order to ensure that it picks up the environment variables. To learn more about the Visual Studio Code CLI, you can check out the docs page.
On Windows (requires PowerShell):
# The extra dot at the beginning is required to 'dot source' this file into the right scope.
. .\activate.ps1
code .
On macOS/Linux:
source activate.sh
code .
💡 Note that if you are using the "Remote-WSL" extension in VSCode, the environment is not supplied to the process in WSL. You can workaround this by explicitly setting the environment variables in
~/.vscode-server/server-env-setup
. See https://code.visualstudio.com/docs/remote/wsl#_advanced-environment-setup-script for details.
When developing in VS Code, you'll need to use the build.cmd
or build.sh
scripts in order to build the project. You can learn more about the command line options available, check out the section below.
⚠️ Most of the time, you will want to build a particular project instead of the entire repository. It's faster and will allow you to focus on a particular area of concern. If you need to build all code in the repo for any reason, you can use the top-level build script located undereng\build.cmd
oreng\build.sh
.
The source code in this repo is divided into directories for each project area. Each directory will typically contain a src
directory that contains the source files for a project and a test
directory that contains the test projects and assets within a project.
Some projects, like the Components
project or the Razor
project, might contain additional subdirectories.
To build a code change associated with a modification, run the build script in the directory closest to the modified file. For example, if you've modified src/Components/WebAssembly/Server/src/WebAssemblyNetDebugProxyAppBuilderExtensions.cs
then run the build script located in src/Components
.
On Windows, you can run the command script:
.\build.cmd
On macOS/Linux, you can run the shell script:
./build.sh
💡 Before using the
build.cmd
orbuild.sh
at the top-level or in a subfolder, you will need to make sure that the dependencies documented above have been installed.
By default, all of the C# projects are built. Some C# projects require NodeJS to be installed to compile JavaScript assets which are then checked in as source. If NodeJS is detected on the path, the NodeJS projects will be compiled as part of building C# projects. If NodeJS is not detected on the path, the JavaScript assets checked in previously will be used instead. To disable building NodeJS projects, specify -noBuildNodeJS
or --no-build-nodejs
on the command line.
At this point, you will have all the dependencies installed and a code editor to up and running to make changes in. Once you've made changes, you will need to rebuild the project locally to pick up your changes. You'll also need to run tests locally to verify that your changes worked.
The section below provides some helpful guides for using the dotnet
CLI in the ASP.NET Core repo.
Because we are using pre-release versions of .NET Core, you have to set a handful of environment variables to make the .NET Core command line tool work well. You can set these environment variables like this:
On Windows (requires PowerShell):
# The extra dot at the beginning is required to 'dot source' this file into the right scope.
. .\activate.ps1
On macOS/Linux:
source ./activate.sh
💡 Be sure to set the environment variables using the "activate" script above before executing the
dotnet
command inside the repo.
Tests are not run by default. When invoking a build.cmd
/build.sh
script, use the -test
option to run tests in addition to building.
On Windows:
.\build.cmd -test
On macOS/Linux:
./build.sh --test
💡 If you're working on changes for a particular subset of the project, you might not want to execute the entire test suite. Instead, only run the tests within the subdirectory where changes were made. This can be accomplished by passing the
projects
property like so:.\build.cmd -test -projects .\src\Framework\test\Microsoft.AspNetCore.App.UnitTests.csproj
.
Additional properties can be added as an argument in the form /property:$name=$value
, or /p:$name=$value
for short. For example:
.\build.cmd -Configuration Release
Common properties include:
Property | Description |
---|---|
Configuration | Debug or Release . Default = Debug . |
TargetArchitecture | The CPU architecture to build for (x64, x86, arm, arm64). |
TargetOsName | The base runtime identifier to build for (win, linux, osx, linux-musl). |
After making changes to a .resx file, the updated strings and accessor methods will automatically be included in the output assembly when the project is next built.
After building ASP.NET Core from source, you will need to install and use your local version of ASP.NET Core. See "Artifacts" for more explanation of the different folders produced by a build.
Building installers does not run as part of build.cmd
run without parameters, so you should opt-in for building them:
.\build.cmd -all -pack -arch x64
.\build.cmd -all -pack -arch x86 -noBuildJava
.\build.cmd -buildInstallers
Note: Additional build steps listed above aren't necessary on Linux or macOS.
-
Run the installers produced in
artifacts/installers/{Debug, Release}/
for your platform. -
Add a NuGet.Config to your project directory with the following content:
<?xml version="1.0" encoding="utf-8"?> <configuration> <packageSources> <clear /> <add key="MyBuildOfAspNetCore" value="C:\src\aspnet\AspNetCore\artifacts\packages\Debug\Shipping\" /> <add key="NuGet.org" value="https://api.nuget.org/v3/index.json" /> </packageSources> </configuration>
NOTE: This NuGet.Config should be with your application unless you want nightly packages to potentially start being restored for other apps on the machine.
-
Update the versions on
PackageReference
items in your .csproj project file to point to the version from your local build.<ItemGroup> <PackageReference Include="Microsoft.AspNetCore.SpaServices" Version="3.0.0-dev" /> </ItemGroup>
Some features, such as new target frameworks, may require prerelease tooling builds for Visual Studio. These are available in the Visual Studio Preview.
See BuildErrors for a description of common issues you might run into while building the repo.