xamarin-macios/eng

The eng folder contains and is used by parts of the https://github.com/dotnet/arcade SDK.

Dependency Management

The Arcade SDK contains a tool known as darc, which can be used to manage and query the relationships between repositories in the dotnet ecosystem.

The eng/Version.Details.xml and eng/Versions.props files contain information about the products and tooling that this repository depends on.

Many dotnet repositories use a publishing workflow that will push build artifact data to a central location known as the "Build Asset Registry". This data includes a "channel" association, which is used to determine when an update for a particular product or tool is available. Local updates and automatic update "subscriptions" compare the version files in the repository against the versions avalable in the channel that you are interested in. The darc tool is used facilitate these updates.

To work with darc locally, see the setting up your darc client docs. You'll need to run a script in the dotnet/arcade repo to install the dotnet global tool, join the arcade-contrib GitHub team, and run the darc authenticate command to add the PATs required by the tool.

The GitHub PAT that you add must have the full repo scope enabled if you want to work with any of the subcription commands. You'll also have to enable SSO (for the xamarin org). Subscriptions control the automated creation of dependency update pull requests.

To add a new dependency, run the darc add-dependency command at the root of the repository:

darc add-dependency -n Microsoft.NetCore.App.Runtime.ios-arm64 -t product -v 6.0.0-preview.2.21154.6 -r https://github.com/dotnet/runtime

To update all dependencies, use the darc update-dependencies command:

darc update-dependencies --channel ".NET 6"

To configure automatic updates, use the darc add-subscription command to enroll a target repo/branch into updates from a particular channel:

darc add-subscription --channel ".NET 6" --source-repo https://github.com/dotnet/installer --target-repo https://github.com/xamarin/xamarin-macios --target-branch main --update-frequency everyWeek --standard-automerge

To configure automatic updates for a release branch, use the following arguments:

darc add-subscription --channel ".NET 6.0.1xx SDK Preview 5" --source-repo https://github.com/dotnet/installer --target-repo https://github.com/xamarin/xamarin-macios --target-branch release/6.0.1xx-preview5 --update-frequency everyDay

Once a subscription is configured, pull requests will be created automatically by the dotnet Maestro bot whenever dependency updates are available.

Subscriptions need to be manually managed at this time. For example, when a release branch is created, someone with darc installed locally will need to run the add-subscription command to configure updates against that new branch.

Build Asset Manifest Promotion

Builds from main and release branches will push NuGet package metadata to the darc/maestro Build Asset Registry. This build information will also be promoted to a default darc/maestro channel if one is configured. Default channels are manually managed at this time. To configure a new default repo+branch <-> channel association, run the darc add-default-channel command:

darc add-default-channel --channel ".NET 6" --branch "main" --repo https://github.com/xamarin/xamarin-macios

When a new release branch is created, this command should look something like this:

darc add-default-channel --channel ".NET 6.0.1xx SDK Preview 4" --branch "release/6.0.1xx-preview4" --repo https://github.com/xamarin/xamarin-macios