Microsoft GH-200 - GitHub Actions Exam

The GITHUB_REPOSITORY environment variable contains the owner and repository name in the format owner/repository. It is automatically provided by GitHub Actions and can be used to reference the repository in workflows.

You can enable specific actions for the organization by identifying them and providing version control, ensuring only trusted versions are used in workflows.

GitHub-verified actions can be enabled at the enterprise level, providing an extra layer of security by ensuring that only trusted actions are available to workflows.

Actions can be published to an internal marketplace, allowing organizations to share reusable actions securely within their enterprise without exposing them to the public.

Creating a separate repository for each custom action allows you to manage the versioning independently for each action. This approach provides flexibility, as each action can be updated, tested, and versioned separately, avoiding potential conflicts or dependencies between different actions.

The check_run event is triggered when a check (such as a code quality check) completes, including when the status of a check changes. By adding this event as a trigger, you can initiate a follow-up workflow when the code quality integration finishes its checks.

A composite action is identified by its action metadata file. In action.yml or action.yaml, the runs section must define using: " composite " . This tells GitHub Actions that the action is a composite action made from one or more reusable workflow steps. Option A is incorrect because Dockerfile and package.json files do not identify a composite action; they are usually associated with Docker or JavaScript-based projects. Option C is wrong because repository naming has no technical meaning in action classification. Option D is also wrong because an init.sh file is merely a script and does not define the action type. GitHub’s metadata syntax states that composite actions require runs.using to be set to composite.

To target a specific self-hosted runner, the job must use runs-on with labels that match that runner. A self-hosted runner normally has the self-hosted label plus default labels and any custom labels you assign. Since the runner is labeled runner1, the workflow should specify both self-hosted and runner1: runs-on: [self-hosted, runner1]. GitHub Actions will then route the job only to a self-hosted runner matching all specified labels. Option A targets a different custom label. Option B is malformed and also mixes a self-hosted label with a GitHub-hosted runner label. Option D targets any self-hosted runner, not specifically runner1. GitHub documents that an array of runs-on labels requires a runner matching all listed labels.

The most secure option listed is to use OIDC-based integration to obtain short-lived credentials from an external secrets manager or cloud provider. This avoids storing long-lived sensitive values directly in workflow YAML, repository text, or regular environment variables. Options A, B, and C are insecure because they expose or persist sensitive information in places that can be read, logged, committed, or mismanaged. With OIDC, the workflow requests a token from GitHub’s OIDC provider and exchanges it with the trusted external provider for a short-lived credential. This reduces secret sprawl and supports stronger authorization controls. GitHub documents OIDC as a way to avoid duplicating long-lived cloud credentials as GitHub secrets and to use short-lived access tokens instead.

The runs-on keyword allows you to specify the operating system and other labels for the runner. By specifying self-hosted, windows, and x64, you are targeting a self-hosted Windows runner that matches these criteria, which aligns with the custom configuration of your self-hosted runner.

A JavaScript action is identified in its action metadata file by the runs.using runtime value. In older exam-style content, this is commonly shown as node16; in current GitHub documentation, supported JavaScript runtimes have moved forward, but the principle remains the same: JavaScript actions declare a Node.js runtime under runs.using and specify the main JavaScript file under runs.main. Option A is not reliable because a repository can contain package.json without being a JavaScript action. Option B is unrelated because workflow files do not define the action type. Option C is naming-based and has no technical meaning. GitHub metadata syntax defines runs.using as the runtime for JavaScript actions.

The most common way to target a major release version of a GitHub Action is to reference a version tag such as @v3. This allows the workflow to use updates within that major version while avoiding automatic jumps to a newer major version that might introduce breaking changes. Option A references a commit SHA, which is the safest and most immutable method, but it is not the most common way to target a major release version. Option B is not a standard action version reference. Option D omits a version entirely, which is unsafe and not recommended because the action reference is incomplete. This topic maps to action versioning, marketplace action consumption, and reliable workflow maintenance.

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