Github Actions
Mathew Letter
Automate, customize, and execute your software development workflows right in your repository with GitHub Actions. You can discover, create, and share actions to perform any job you'd like, including CI/CD, and combine actions in a completely customized workflow.
A single workflow can be triggered by multiple schedule events. You can access the schedule event that triggered the workflow through the github.event.schedule context. This example triggers the workflow to run at 5:30 UTC every Monday-Thursday, but skips the Not on Monday or Wednesday step on Monday and Wednesday.
You can use permissions either as a top-level key, to apply to all jobs in the workflow, or within specific jobs. When you add the permissions key within a specific job, all actions and run commands within that job that use the GITHUB_TOKEN gain the access rights you specify. For more information, see jobs..permissions.
Use concurrency to ensure that only a single job or workflow using the same concurrency group will run at a time. A concurrency group can be any string or expression. The expression can only use github, inputs and vars contexts. For more information about expressions, see "Expressions."
This means that when a workflow run or job starts, GitHub will cancel any workflow runs or jobs that are already in progress in the same concurrency group. This is useful in scenarios where you want to prevent parallel runs for a certain set of a workflows or jobs, such as the ones used for deployments to a staging environment, in order to prevent actions that could cause conflicts or consume more resources than necessary.
Alternatively, using a dynamic expression such as concurrency: ci-$ github.ref in your workflow means that the workflow or job would be part of a concurrency group named ci- followed by the reference of the branch or tag that triggered the workflow. In this example, if a new commit is pushed to the main branch while a previous run is still in progress, the previous run will be cancelled and the new one will start:
If you build the group name with a property that is only defined for specific events, you can use a fallback value. For example, github.head_ref is only defined on pull_request events. If your workflow responds to other events in addition to pull_request events, you will need to provide a fallback to avoid a syntax error. The following concurrency group cancels in-progress jobs or runs on pull_request events only; if github.head_ref is undefined, the concurrency group will fallback to the run ID, which is guaranteed to be both unique and defined for the run.
You can use jobs..concurrency to ensure that only a single job or workflow using the same concurrency group will run at a time. A concurrency group can be any string or expression. Allowed expression contexts: github, inputs, vars, needs, strategy, and matrix. For more information about expressions, see "Expressions."
A job contains a sequence of tasks called steps. Steps can run commands, run setup tasks, or run an action in your repository, a public repository, or an action published in a Docker registry. Not all steps run actions, but all actions run as a step. Each step runs in its own process in the runner environment and has access to the workspace and filesystem. Because steps run in their own process, changes to environment variables are not preserved between steps. GitHub provides built-in steps to set up and complete a job.
The path is relative (./) to the default working directory (github.workspace, $GITHUB_WORKSPACE). If the action checks out the repository to a location different than the workflow, the relative path used for local actions must be updated.
Public actions may specify expected variables in the README file. If you are setting a secret or sensitive value, such as a password or token, you must set secrets using the secrets context. For more information, see "Contexts."
For example, the following workflow defines the variable version with the values [10, 12, 14]. The workflow will run three jobs, one for each value in the variable. Each job will access the version value through the matrix.version context and pass the value as node-version to the actions/setup-node action.
The workflow will run six jobs, one for each combination of the os and version variables. Each job will set the runs-on value to the current os value and will pass the current version value to the actions/setup-node action.
Use jobs..container to create a container to run any steps in a job that don't already specify a container. If you have steps that use both script and container actions, the container actions will run as sibling containers on the same network with the same volume mounts.
If you configure your job to run in a container, or your step uses container actions, you don't need to map ports to access the service or action. Docker automatically exposes all ports between containers on the same Docker user-defined bridge network. You can directly reference the service container by its hostname. The hostname is automatically mapped to the label name you configure for the service in the workflow.
Workflows are defined in the .github/workflows directory in a repository, and a repository can have multiple workflows, each of which can perform a different set of tasks. For example, you can have one workflow to build and test pull requests, another workflow to deploy your application every time a release is created, and still another workflow that adds a label every time someone opens a new issue.
Optional - The name for workflow runs generated from the workflow, which will appear in the list of workflow runs on your repository's "Actions" tab. This example uses an expression with the github context to display the username of the actor that triggered the workflow run. For more information, see "Workflow syntax for GitHub Actions."
The uses keyword specifies that this step will run v4 of the actions/checkout action. This is an action that checks out your repository onto the runner, allowing you to run scripts or other actions against your code (such as build and test tools). You should use the checkout action any time your workflow will use the repository's code.
In this diagram, you can see the workflow file you just created and how the GitHub Actions components are organized in a hierarchy. Each step executes a single action or shell script. Steps 1 and 2 run actions, while steps 3 and 4 run shell scripts. To find more prebuilt actions for your workflows, see "Finding and customizing actions."
Unfortunately, at this time we are not able to support the extension with remote repositories (including github.dev and vscode.dev), so please use the extension with locally downloaded GitHub repositories for the best experience. Please check back here for updates in the future!
The issue_comment event occurs for comments on both issues and pull requests. You can use the github.event.issue.pull_request property in a conditional to take different action depending on whether the triggering object was an issue or pull request.
Note that GITHUB_SHA for this event is the last merge commit of the pull request merge branch. If you want to get the commit ID for the last commit to the head branch of the pull request, use github.event.pull_request.head.sha instead.
To run a job based on the pull request's head branch name (as opposed to the pull request's base branch name), use the github.head_ref context in a conditional. For example, this workflow will run whenever a pull request is opened, but the run_if job will only execute if the head of the pull request is a branch whose name starts with releases/:
To run your workflow when a pull request has been approved, you can trigger your workflow with the submitted type of pull_request_review event, then check the review state with the github.event.review.state property. For example, this workflow will run whenever a pull request review is submitted, but the approved job will only run if the submitted review is an approving review:
Any data that you send through the client_payload parameter will be available in the github.event context in your workflow. For example, if you send this request body when you create a repository dispatch event:
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