mono Validate Samples
Automates the workflow for building SkiaSharp samples against CI-produced NuGet packages. The samples use package references (not project references) when built through the cake target, so they need downloadable NuGet packages.
When to Use
- After making changes to samples and wanting to verify they build
- When CI reports sample build failures and you need to reproduce locally
- When validating that a new SkiaSharp release doesn't break samples
- After merging changes that affect sample project files or dependencies
Workflow
Step 1: Clear cached packages
rm -r -fo externals/package_cache/skiasharp*, externals/package_cache/harfbuzzsharp*
If you suspect deeper caching issues, also clear the global NuGet cache:
dotnet nuget locals all --clear
Step 2: Download CI packages
Choose the source that actually owns the packages.
For the latest promoted build from main or another promoted branch, use the
transport feed:
dotnet cake --target=docs-download-output
# From a specific branch
dotnet cake --target=docs-download-output --gitBranch=release/3.119.4
PR builds are pipeline artifacts and are not published to the transport feed. Download them with the repository helper, then copy the packages into the sample workflow's expected directory:
pwsh scripts/get-skiasharp-pr.ps1 3553 -Force
New-Item output/nugets -ItemType Directory -Force | Out-Null
Copy-Item ~/.skiasharp/hives/pr-3553/packages/*.nupkg output/nugets/
For an exact non-PR commit, resolve its public definition-345 Build ID, download
that run's canonical nuget artifact, and extract non-symbol .nupkg files into
output/nugets/. Do not query the transport feed by SHA; BAR publishes one
branch-versioned transport package per ID.
Step 3: Detect the preview version
Run the detection script — it prints the preview label and build number extracted from the downloaded nupkg filenames:
pwsh .agents/skills/validate-samples/scripts/detect-preview-version.ps1
Output:
Found: SkiaSharp.3.119.4-preview.0.76.nupkg
Preview label: preview.0
Build number: 76
Full suffix: preview.0.76
Parse Preview label and Build number from the output for the next step.
Step 4: Build samples
dotnet cake --target=samples --previewLabel=<PREVIEW_LABEL> --buildNumber=<BUILD_NUMBER>
To build a single sample, add --sample=<name>:
dotnet cake --target=samples --previewLabel=<PREVIEW_LABEL> --buildNumber=<BUILD_NUMBER> --sample=Blazor
Troubleshooting
Stale packages after repeated runs
rm -r -fo externals/package_cache/skiasharp*, externals/package_cache/harfbuzzsharp*
dotnet nuget locals all --clear
Platform-specific samples not building
Some platforms are disabled by default:
# Pass these MSBuild properties to enable optional platforms
-p:IsNetTVOSSupported=true
-p:IsNetTizenSupported=true
-p:IsNetMacOSSupported=true
WinUI XAML compiler crash on .NET 10
May need a newer Microsoft.WindowsAppSDK version.
"The local source 'packages' doesn't exist" (Docker samples)
Docker samples are built via run.ps1 inside Docker, not dotnet build.
The samples-prepare target copies nupkgs there automatically.
Further Reading
See Building Samples for version construction
details, download resolution, cake arguments reference, and how samples-generate works.