GH-200 GitHub Actions Exam Questions and Answers

A Docker container action is ideal for custom actions that require specific environments or dependencies, such as Python. By creating a Docker container, you can define the environment with the necessary Python version and dependencies, and your Python code can run inside that container.

Scheduled workflows in GitHub Actions are triggered at specified times, and they run on the latest commit of the branch that triggers the workflow. This means the workflow will run on the most recent commit on the branch that was active at the time the scheduled event occurs.

Workflow commands are special commands that allow you to interact with the runner, set environment variables, output values, add debug messages, and perform other tasks within the workflow. These commands are used to modify the environment or influence the behavior of the GitHub Actions runner.

Caching is ideal for files that change rarely, such as dependencies or build outputs, as it speeds up subsequent workflow runs by reusing previously cached files instead of re-downloading or rebuilding them.

Artifacts are used for persisting files produced during a job that need to be used in later jobs or after the workflow has ended, allowing them to be downloaded or referenced later.

A. Use the actions/setup-docker action

B. Authenticate to the GitHub Container Registry.

C. Build the container image.

D. Push the image to the GitHub Container Registry

E. Pull the image from the GitHub Container Registry.

The GITHUB_REF environment variable specifies the branch or tag that triggered the workflow. It contains the full reference to the branch or tag, such as refs/heads/main for a branch or refs/tags/v1.0 for a tag.

Required reviewers is a protection rule where you can specify that certain individuals or teams must review and approve the workflow run before it can proceed. This is used to enforce approvals before certain steps or environments are accessed.

Wait timer is a protection rule that introduces a delay before a workflow can proceed to the next stage. This is useful for adding time-based constraints to the deployment process or ensuring that certain conditions are met before a workflow continues.

The GET /repos/:owner/:repo/actions/runs/:run_id/logs API endpoint is used to retrieve the logs of a specific workflow run identified by run_id. This is the correct method for downloading logs from a workflow run.

The correct syntax for specifying a cleanup script to be run after the main entry point is executed in a Docker-based GitHub Action is to use the post key. This ensures that cleanup.sh runs after the main script (main.sh) has completed.

To scope a secret to a specific repository, you can create a new secret with a name like MyRepo_SuperSecret in the secrets section of the MyRepo repository's settings. This ensures that the secret is specific to that repository and can be used within its workflows.

The action.yml file is the metadata file in a custom GitHub Action that defines the main entry point, including information such as the inputs, outputs, description, and the runs key that specifies the main entry point (e.g., a script or a Docker container).

The publish-npm job includes the JS-DevTools/npm-publish action, which is used to publish an npm package to an npm registry.

The publish-npm job has the needs: build directive, meaning it will only run after the build job successfully completes.

GitHub-hosted runners have a limit on the number of concurrent workflows (typically 20 for free-tier accounts and 5 for enterprise). If your organization needs to run more workflows simultaneously, you would need to use self-hosted runners to increase the available concurrency.

Self-hosted runners allow you to configure specialized hardware or software setups that are necessary for certain workflows. GitHub-hosted runners may not have access to custom hardware configurations like GPUs or other specialized resources, so self-hosted runners are required in such cases.

GITHUB_WORKSPACE is a default environment variable in GitHub Actions that points to the directory on the runner where your repository is checked out. This variable allows you to access files within your repository during the workflow.

A matrix strategy allows you to define different versions of a programming language (or any other environment setting) and run tests on each version simultaneously. This is particularly useful for testing code compatibility across different versions of a language.

A matrix strategy can also be used to test code on multiple operating systems (e.g., Windows, macOS, Linux) by defining these operating systems as matrix variables. This enables cross-platform testing within the same workflow.

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.

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.

The smallest scope for an environment variable is within a step. Environment variables defined within a step are only accessible to that particular step, which makes it the smallest scope for a variable in a GitHub Actions workflow.