Download GitHub Actions Exam.GH-200.Actual4Test.2026-05-21.101q.vcex

Reusable workflows versus composite actionsReusable workflows and composite actions both help you avoid duplicating workflow content.Whereas reusable workflows allow you to reuse an entire workflow, with multiple jobs and steps, composite actions combine multiple steps that you can then run within a job step, just like any other action.A composite action allows you to bundle multiple steps into a single reusable action within a workflow. It is composed of multiple run steps or other actions and can be reused across workflows, making it the perfect choice for bundling a series of steps.Reference:https://docs.github.com/en/actions/concepts/workflows-and-actions/reusable-workflows

[D] To authenticate to a GitHub Packages registry within a GitHub Actions workflow, you can use:*-> GITHUB_TOKEN to publish packages associated with the workflow repository.* A personal access token (classic) with at least read:packages scope to install packages associated with other private repositories (GITHUB_TOKEN can be used if the repository is granted read access to the package.[E] You can use the GITHUB_TOKEN to make authenticated API calls. This example workflow creates an issue using the GitHub REST API:Reference:https://docs.github.com/en/packages/learn-github-packages/introduction-to-github-packageshttps://docs.github.com/en/actions/tutorials/authenticate-with-github_token

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.

REST API endpoints for workflow jobsYou can use the REST API to view logs and workflow jobs in GitHub Actions.Download job logs for a workflow runGets a redirect URL to download a plain text file of logs for a workflow job.Code samples for "Download job logs for a workflow run"Request exampleGet /repos/{owner}/{repo}/actions/jobs/{job_id}/logsReference:https://docs.github.com/en/rest/actions/workflow-jobs

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.

Default environment variablesThe default environment variables that GitHub sets are available to every step in a workflow.Because default environment variables are set by GitHub and not defined in a workflow, they are not accessible through the env context [Not B]. However, most of the default variables have a corresponding, and similarly named, context property. For example, the value of the GITHUB_REF variable can be read during workflow processing using the ${{ github.ref }} context property.Reference:https://docs.github.com/en/actions/reference/workflows-and-actions/variables

The ::debug:: syntax is used to output debug messages in GitHub Actions workflows. This command will print the message "action successfully debugged" in the debug logs when the workflow runs.

The needs context is used to reference the outputs of jobs that are dependencies of the current job. In this case, needs.job1.outputs.output1 correctly accesses the output of output1 from the job job1 in the dependent job.

The workflow_call event is used to trigger a reusable workflow from another workflow. This allows you to create workflows that can be reused in multiple places within your organization, enabling better modularity and reducing duplication.

A custom GitHub Action's inputs, outputs, and other configurations are defined in its metadata file, which must be named action.yml or action.yaml and placed at the root of the action's repository. This YAML file specifies how the action runs (e.g., using Docker or JavaScript) and provides the metadata for its inputs and outputs, which are then used by workflows that call the action.Key aspects of the action.yml or action.yaml fileFormat: It uses YAML syntax.Location: It must be in the root directory of your action's repository.Contents: It defines the action's name, description, inputs, outputs, and the runs configuration to specify the execution environment (like a Docker image or JavaScript file) and entrypoint.Inputs and Outputs: The file includes inputs and outputs sections to declare the data the action accepts and produces, respectively.Reference:https://docs.github.com/en/actions/reference/workflows-and-actions/metadata-syntax