dotnet restore command in dotnet

The command dotnet restore in the .NET CLI is used to restore the dependencies for a .NET project based on the information specified in the project's .csproj file. Here’s why it's called restore instead of install:

1. Understanding Dependency Management

• Dependency Resolution: When you add packages (dependencies) to a .NET project using NuGet, these packages are listed in the .csproj file. However, the actual package files (*.dll, etc.) are not stored in your project directory by default.

• Restore vs. Install:

  • Restore: The term "restore" refers to the process of downloading and installing the actual package files (*.nupkg) from the specified NuGet package sources. This process ensures that all required dependencies are available locally for building the project.

  • Install: The term "install" typically refers to the action of placing or configuring software onto a computer system so that it can be used. In the context of .NET CLI, "installing" packages would imply more than just restoring the dependencies; it would involve configuring them for use, which dotnet restore does not directly handle.

2. Why restore?

• Historical Context: The term "restore" originates from the concept of restoring dependencies to a project's local environment. It aligns with the process of ensuring that all necessary packages are available and ready for use in the development environment.

• Specific Purpose: dotnet restore focuses solely on the action of retrieving and making available the necessary package files. It doesn't imply configuration or setup beyond ensuring that the project has access to the required dependencies.

3. Practical Use

When you run dotnet restore, it performs the following actions:

• Contacts the configured NuGet package sources (e.g., nuget.org) to check for updates and download any new or updated packages.
• Downloads the package files (*.nupkg) to a local cache (usually under the user's profile directory).
• Updates the project's dependencies so that subsequent build (dotnet build) and run (dotnet run) commands can find and use these packages.