Add AmbientMetadata.Build component

[evgenyfedorov2]

Adding a brand new component - Build metadata, which automatically grabs build information from the CI/CD pipelines, deserializes it into a strong type BuildMetadata and registers it in Dependency Injection container as IOptions<BuildMetadata>.
The component uses source generation to collect build information and immediately express it via C# code.

Initially, only GitHub Actions and Azure DevOps are supported

Microsoft Reviewers: Open in CodeFlow

[dariusclay]

I love porting until I realize my commit history is lost. 🤣

[slang25]

Couldn't this alternatively be fetched by the InitializeSourceControlInformation and related targets in MSBuild that are used for SourceLink, that way this would work for local builds as well as CI.

[evgenyfedorov2]

updated to fetch data from MSBuild properties, which by default are initialized from environment variables.

[KalleOlaviNiemitalo]

What's the purpose of the empty src/Libraries/Microsoft.Extensions.AmbientMetadata.Build/Microsoft.Extensions.AmbientMetadata.Build.json file?

[evgenyfedorov2]

What's the purpose of the empty src/Libraries/Microsoft.Extensions.AmbientMetadata.Build/Microsoft.Extensions.AmbientMetadata.Build.json file?

Removed :)

[Copilot]

Pull Request Overview

This PR introduces a new AmbientMetadata.Build component that provides automatic build metadata collection from CI/CD pipelines. The component uses source generation to extract build information at compile time and register it in the dependency injection container as IOptions.

Key changes:

• New BuildMetadata class with properties for build ID, number, branch name, and source version
• Source generator that reads MSBuild properties and generates configuration extensions
• Support for both Azure DevOps and GitHub Actions CI environments

Reviewed Changes

Copilot reviewed 20 out of 24 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/Libraries/Microsoft.Extensions.AmbientMetadata.Build/BuildMetadata.cs	Defines the core data model for build metadata
src/Generators/Microsoft.Gen.BuildMetadata/BuildMetadataGenerator.cs	Main source generator that creates build metadata extensions
src/Libraries/Microsoft.Extensions.AmbientMetadata.Build/BuildMetadataServiceCollectionExtensions.cs	Extension methods for registering BuildMetadata in DI container
src/Libraries/Microsoft.Extensions.AmbientMetadata.Build/buildTransitive/Microsoft.Extensions.AmbientMetadata.Build.props	MSBuild properties file that maps CI environment variables to build properties
test/Libraries/Microsoft.Extensions.AmbientMetadata.Build.Tests/	Unit tests for the build metadata functionality

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[Copilot]

Pull Request Overview

Copilot reviewed 20 out of 24 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 20 out of 24 changed files in this pull request and generated 2 comments.

---

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[Copilot]

The boolean parsing logic only recognizes 'true' as true and treats everything else (including 'false') as false. Consider using bool.TryParse for more robust boolean parsing that handles both 'true' and 'false' values correctly.

Suggested change

	return !string.IsNullOrEmpty(value) &&
	string.Equals(value, "true", System.StringComparison.OrdinalIgnoreCase);
	return bool.TryParse(value, out var result) && result;