website: add a guide for running Lima on GHA

Lima is also useful for:
- Running commands on non-Ubuntu operating systems such as Fedora
- Emulating multiple hosts

Signed-off-by: Akihiro Suda <[email protected]>

website/content/en/docs/examples/gha.md

@@ -0,0 +1,90 @@
+---
+title: GitHub Actions
+weight: 10
+---
+
+## Running Lima on GitHub Actions
+
+Lima is also useful for:
+- Running commands on non-Ubuntu operating systems (e.g., Fedora for testing SELinux)
+- Emulating multiple hosts.
+
+These tasks can be also partially accomplished with containers like Docker,
+but they are still stick to Ubuntu's kernel configuration and cannot use non-Ubuntu features such as SELinux.
+
+On the other hand, Lima executes virtual machines that are decoupled from Ubuntu's kernel.
+
+```yaml
+name: Fedora
+
+on:
+  workflow_dispatch:
+  pull_request:
+
+jobs:
+  fedora:
+    runs-on: ubuntu-24.04
+    steps:
+    - name: Check out code
+      uses: actions/checkout@v4
+
+    - name: "Install QEMU"
+      run: |
+        set -eux
+        sudo apt-get update
+        sudo apt-get install -y --no-install-recommends ovmf qemu-system-x86 qemu-utils
+        sudo modprobe kvm
+        # `sudo usermod -aG kvm $(whoami)` does not take an effect on GHA
+        sudo chown $(whoami) /dev/kvm
+
+    - name: "Install Lima"
+      run: |
+        set -eux
+        LIMA_VERSION=$(curl -fsSL https://api.github.com/repos/lima-vm/lima/releases/latest | jq -r .tag_name)
+        curl -fsSL https://github.com/lima-vm/lima/releases/download/${LIMA_VERSION}/lima-${LIMA_VERSION:1}-Linux-x86_64.tar.gz | sudo tar Cxzvf /usr/local -
+
+    - name: "Cache ~/.cache/lima"
+      uses: actions/cache@v4
+      with:
+        path: ~/.cache/lima
+        key: lima-${{ env.LIMA_VERSION }}
+
+    - name: "Start an instance of Fedora"
+      run: |
+        set -eux
+        limactl start --name=default --cpus=1 --memory=1 --network=lima:user-v2 template://fedora
+        lima sudo dnf install -y httpd
+        lima sudo systemctl enable --now httpd
+
+    - name: "Start another instance of Fedora"
+      run: |
+        set -eux
+        limactl start --name=another --cpus=1 --memory=1 --network=lima:user-v2 template://fedora
+        limactl shell another curl http://lima-default.internal
+```
+
+### Plain mode
+
+The `--plain` mode is useful when you want the VM instance to be as close as possible to physical hosts:
+
+```yaml
+    - name: "Start Fedora"
+      # --plain is set to disable file sharing, port forwarding, built-in containerd, etc.
+      run: limactl start --plain --name=default --cpus=1 --memory=1 --network=lima:user-v2 template://fedora
+
+    - name: "Initialize Fedora"
+      # plain old rsync and ssh are used for the initialization of the guest,
+      # so that people who are not familiar with Lima can understand the initialization steps.
+      run: |
+        set -eux -o pipefail
+        # Initialize SSH
+        mkdir -p -m 0700 ~/.ssh
+        cat ~/.lima/default/ssh.config >> ~/.ssh/config
+        # Sync the current directory to /tmp/repo in the guest
+        rsync -a -e ssh . lima-default:/tmp/repo
+        # Install packages
+        ssh lima-default sudo dnf install -y httpd
+```
+
+### Full examples
+- https://github.com/kubernetes-sigs/kind/blob/v0.25.0/.github/workflows/vm.yaml#L47-L84