# Install SSH Key

[![Build][image-build]][link-build]
[![Windows][image-verify-windows]][link-verify-windows]
[![macOS][image-verify-macos]][link-verify-macos]
[![Ubuntu][image-verify-ubuntu]][link-verify-ubuntu]
[![Ubuntu 16.04][image-verify-ubuntu1604]][link-verify-ubuntu1604]
[![Release][image-release]][link-release]
[![License][image-license]][link-license]
[![Stars][image-stars]][link-stars]

This action installs SSH key in `~/.ssh`.

Useful for SCP, SFTP, and `rsync` over SSH in deployment script.

**Works on all [virtual environment](https://help.github.com/en/actions/automating-your-workflow-with-github-actions/virtual-environments-for-github-hosted-runners#supported-runners-and-hardware-resources) -- Windows, macOS, Ubuntu and Ubuntu 16.04.**

## Usage

Add your SSH key to your product secrets by clicking `Settings` - `Secrets` - `Add a new secret` beforehand.

**NOTE:** OPENSSH format (key begins with `-----BEGIN OPENSSH PRIVATE KEY-----`) may not work due to OpenSSH version on VM. Please use PEM format (begins with `-----BEGIN RSA PRIVATE KEY-----`) instead.

```yaml
runs-on: ubuntu-latest
steps:
- name: Install SSH key
  uses: shimataro/ssh-key-action@v1
  with:
    private-key: ${{ secrets.SSH_KEY }}
    name: id_rsa # optional
    known-hosts: ${{ secrets.KNOWN_HOSTS }} # known_hosts; optional
    config: ${{ secrets.CONFIG }} # ssh_config; optional
- name: rsync over ssh
  run: rsync ./foo/ user@remote:bar/
```

See [Workflow syntax for GitHub Actions](https://help.github.com/en/articles/workflow-syntax-for-github-actions) for details.

### Install multiple keys

If you want to install multiple keys, call this action multiple times.
It is useful for port forwarding.

**NOTE:**  When this action is called multiple times, **the contents of `known-hosts` and `config` will be appended**. `private-key` must be saved as different name, by using `name` option.

```yaml
runs-on: ubuntu-latest
steps:
- name: Install SSH key of bastion
  uses: shimataro/ssh-key-action@v1
  with:
    private-key: ${{ secrets.SSH_KEY_OF_BASTION }}
    name: id_rsa-bastion
    known-hosts: ${{ secrets.KNOWN_HOSTS_OF_BASTION }}
    config: |
      Host bastion
        HostName xxx.xxx.xxx.xxx
        User user-of-bastion
        IdentityFile ~/.ssh/id_rsa-bastion
- name: Install SSH key of target
  uses: shimataro/ssh-key-action@v1
  with:
    private-key: ${{ secrets.SSH_KEY_OF_TARGET }}
    name: id_rsa-target
    known-hosts: ${{ secrets.KNOWN_HOSTS_OF_TARGET }} # will be appended!
    config: |                                         # will be appended!
      Host target
        HostName yyy.yyy.yyy.yyy
        User user-of-target
        IdentityFile ~/.ssh/id_rsa-target
        ProxyCommand ssh -W %h:%p bastion
- name: SCP via port-forwarding
  run: scp ./foo/ target:bar/
```

## FAQ

### What is the best way for copying files to multiple servers; SCP, SCP via bastion, SFTP, SFTP via bastion, rsync, and rsync via bastion?

I recommend **rsync via bastion**.
It has some advantages over other methods:

* You only need to use this action once in order to connect to bastion from VM. Other methods require to use it multiple times in order to connect to each targets.
* `rsync`:
    * is faster than others.
    * can remove files that don't exist in target.
* SCP:
    * will break files when disconnected during sending.
    * is [deprecated by OpenSSH](https://www.openssh.com/txt/release-8.0) due to outdated and inflexible protocol.
* Using bastion is more secure because:
    * it is not necessarily to expose SSH port on target servers to public.
    * it requires to shutdown only bastion when security incident ―e.g., private key leaked, GitHub jacked― occurs.

## License

The scripts and documentation in this project are released under the [MIT License](LICENSE)

## Changelog

See [CHANGELOG.md](CHANGELOG.md).

[image-build]: https://github.com/shimataro/ssh-key-action/workflows/Build/badge.svg?event=push&branch=v1
[link-build]: https://github.com/shimataro/ssh-key-action
[image-verify-windows]: https://github.com/shimataro/ssh-key-action/workflows/Windows/badge.svg?event=push&branch=v1
[link-verify-windows]: https://github.com/shimataro/ssh-key-action
[image-verify-macos]: https://github.com/shimataro/ssh-key-action/workflows/macOS/badge.svg?event=push&branch=v1
[link-verify-macos]: https://github.com/shimataro/ssh-key-action
[image-verify-ubuntu]: https://github.com/shimataro/ssh-key-action/workflows/Ubuntu/badge.svg?event=push&branch=v1
[link-verify-ubuntu]: https://github.com/shimataro/ssh-key-action
[image-verify-ubuntu1604]: https://github.com/shimataro/ssh-key-action/workflows/Ubuntu%2016.04/badge.svg?event=push&branch=v1
[link-verify-ubuntu1604]: https://github.com/shimataro/ssh-key-action
[image-release]: https://img.shields.io/github/release/shimataro/ssh-key-action.svg
[link-release]: https://github.com/shimataro/ssh-key-action/releases
[image-license]: https://img.shields.io/github/license/shimataro/ssh-key-action.svg
[link-license]: ./LICENSE
[image-stars]: https://img.shields.io/github/stars/shimataro/ssh-key-action.svg
[link-stars]: https://github.com/shimataro/ssh-key-action/stargazers