- **Fast Feedback** - Rather than having to commit/push every time you want to test out the changes you are making to your `.github/workflows/` files (or for any changes to embedded GitHub actions), you can use `act` to run the actions locally. The [environment variables](https://help.github.com/en/actions/configuring-and-managing-workflows/using-environment-variables#default-environment-variables) and [filesystem](https://help.github.com/en/actions/reference/virtual-environments-for-github-hosted-runners#filesystems-on-github-hosted-runners) are all configured to match what GitHub provides.
- **Local Task Runner** - I love [make](<https://en.wikipedia.org/wiki/Make_(software)>). However, I also hate repeating myself. With `act`, you can use the GitHub Actions defined in your `.github/workflows/` to replace your `Makefile`!
When you run `act` it reads in your GitHub Actions from `.github/workflows/` and determines the set of actions that need to be run. It uses the Docker API to either pull or build the necessary images, as defined in your workflow files and finally determines the execution path based on the dependencies that were defined. Once it has the execution path, it then uses the Docker API to run containers for each action based on the images prepared earlier. The [environment variables](https://help.github.com/en/actions/configuring-and-managing-workflows/using-environment-variables#default-environment-variables) and [filesystem](https://help.github.com/en/actions/reference/virtual-environments-for-github-hosted-runners#filesystems-on-github-hosted-runners) are all configured to match what GitHub provides.
When running `act` for the first time, it will ask you to choose image to be used as default.
It will save that information to `~/.actrc`, please refer to [Configuration](#configuration) for more information about `.actrc` and to [Runners](#runners) for information about used/available Docker images.
-a, --actor string user that triggered the event (default "nektos/act")
-b, --bind bind working directory to container, rather than copy
--container-architecture string Architecture which should be used to run containers, e.g.: linux/amd64. Defaults to linux/<yourmachinearchitecture> [linux/amd64]
--defaultbranch string the name of the main branch
--detect-event Use first event type from workflow as event that triggered the workflow
-C, --directory string working directory (default ".")
-n, --dryrun dryrun mode
--env stringArray env to make available to actions with optional value (e.g. --e myenv=foo or -s myenv)
--env-file string environment file to read and use as env in the containers (default ".env")
-e, --eventpath string path to event JSON file
-g, --graph draw workflows
-h, --help help for act
--insecure-secrets NOT RECOMMENDED! Doesn't hide secrets while printing logs.
-j, --job string run job
-l, --list list workflows
-P, --platform stringArray custom image to use per platform (e.g. -P ubuntu-18.04=nektos/act-environments-ubuntu:18.04)
--privileged use privileged mode
-p, --pull pull docker image(s) if already present
-q, --quiet disable logging of output from steps
-r, --reuse reuse action containers to maintain state
-s, --secret stringArray secret to make available to actions with optional value (e.g. -s mysecret=foo or -s mysecret)
--secret-file string file with list of secrets to read from (e.g. --secret-file .secrets) (default ".secrets")
--userns string user namespace to use
-v, --verbose verbose output
-w, --watch watch the contents of the local repo and run when files change
-W, --workflows string path to workflow file(s) (default "./.github/workflows/")
A `MODULE_NOT_FOUND` during `docker cp` command [#228](https://github.com/nektos/act/issues/228) can happen if you are relying on local changes that have not been pushed. This can get triggered if the action is using a path, like:
```yaml
- name: test action locally
uses: ./
```
In this case, you _must_ use `actions/checkout@v2` with a path that _has the same name as your repository_. If your repository is called _my-action_, then your checkout step would look like:
GitHub Actions offers managed [virtual environments](https://help.github.com/en/actions/reference/virtual-environments-for-github-hosted-runners) for running workflows. In order for `act` to run your workflows locally, it must run a container for the runner defined in your workflow file. Here are the images that `act` uses for each runner type and size:
If you need an environment that works just like the corresponding GitHub runner then consider using an image provided by [nektos/act-environments](https://github.com/nektos/act-environments):
- [nektos/act-environments-ubuntu:18.04](https://hub.docker.com/r/nektos/act-environments-ubuntu/tags) - built from the Packer file GitHub uses in [actions/virtual-environments](https://github.com/actions/runner).
To run `act` with secrets, you can enter them interactively, supply them as environment variables or load them from a file. The following options are available for providing secrets:
-`act -s MY_SECRET=somevalue` - use `somevalue` as the value for `MY_SECRET`.
-`act -s MY_SECRET` - check for an environment variable named `MY_SECRET` and use it if it exists. If the environment variable is not defined, prompt the user for a value.
You can provide default configuration flags to `act` by either creating a `./.actrc` or a `~/.actrc` file. Any flags in the files will be applied before any flags provided directly on the command line. For example, a file like below will always use the `nektos/act-environments-ubuntu:18.04` image for the `ubuntu-latest` runner:
Additionally, act supports loading environment variables from an `.env` file. The default is to look in the working directory for the file but can be overridden by:
Every [GitHub event](https://developer.github.com/v3/activity/events/types) is accompanied by a payload. You can provide these events in JSON format with the `--eventpath` to simulate specific GitHub events kicking off an action. For example:
