Merge pull request #5955 from gat786/test-plugin-install

feat: Install Plugins alongside Flux setup in gh actions

.github/workflows/action.yaml

@@ -27,3 +27,41 @@ jobs:
         uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
       - name: Setup flux
         uses: ./action
+
+  plugins:
+    runs-on: ubuntu-latest
+    name: action plugins on ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+      - name: Setup Go
+        uses: actions/setup-go@44694675825211faa026b3c33043df3e48a5fa00 # v6.0.0
+        with:
+          go-version-file: go.mod
+          cache-dependency-path: go.sum
+      - name: Build flux
+        shell: bash
+        run: |
+          set -euo pipefail
+          mkdir -p cmd/flux/manifests "$RUNNER_TEMP/flux-bin"
+          printf "apiVersion: v1\nkind: List\nitems: []\n" > cmd/flux/manifests/dummy.yaml
+          CGO_ENABLED=0 go build -ldflags="-s -w -X main.VERSION=0.0.0-pr" -o "$RUNNER_TEMP/flux-bin/flux" ./cmd/flux
+      - name: Setup flux with plugin
+        id: setup
+        uses: ./action
+        with:
+          version: 0.0.0-pr
+          bindir: ${{ runner.temp }}/flux-bin
+          plugins: |
+            mirror@sha256:91a1e04c2015ee66b1633e362cdb6d4550891b91bf3391a83414b9e9912e53f1
+      - name: Assert plugin installation
+        shell: bash
+        env:
+          ACTION_PLUGIN_DIR: ${{ steps.setup.outputs['plugin-dir'] }}
+        run: |
+          set -euo pipefail
+          test -n "${FLUXCD_PLUGINS:-}"
+          test "$ACTION_PLUGIN_DIR" = "$FLUXCD_PLUGINS"
+          test -x "$FLUXCD_PLUGINS/flux-mirror"
+          flux plugin list
+          flux mirror --help

action/README.md

@@ -12,6 +12,26 @@ steps:
     run: flux version --client
 ```
 
+To install Flux plugins alongside the CLI:
+
+```yaml
+steps:
+  - name: Setup Flux CLI
+    uses: fluxcd/flux2/action@main
+    with:
+      plugins: |
+        mirror@0.0.1
+  - name: Run Flux plugin
+    run: flux mirror --help
+```
+
+Installing plugins requires a Flux version with plugin support (v2.9.0 or later).
+The `plugins` input accepts one plugin per line in `<name>`,
+`<name>@<version>`, or `<name>@<digest>` format. Entries without a version or
+digest install the latest version from the catalog. The `plugin-dir` input is
+only used when `plugins` is set; when plugins are installed, the action exports
+`FLUXCD_PLUGINS` for subsequent steps.
+
 The Flux GitHub Action can be used to automate various tasks in CI, such as:
 
 - [Automate Flux upgrades on clusters via Pull Requests](https://fluxcd.io/flux/flux-gh-action/#automate-flux-updates)

action/action.yml

@@ -12,17 +12,36 @@ inputs:
     description: "arch can be amd64, arm64 or arm"
     required: false
     deprecationMessage: "No longer required, action will now detect runner arch."
+  plugins:
+    description: >
+      Plugins to install alongside Flux. One per line: `<name>`, `<name>@<version>` or
+      `<name>@<digest>`. Entries without a version or digest install the latest
+      version from the catalog. Example: `mirror@0.0.1`
+    required: false
+  plugin-dir:
+    description: >
+      Directory where requested plugins are installed. This input is only used when
+      `plugins` is set. When plugins are installed, the action exports
+      `FLUXCD_PLUGINS` for subsequent steps. Defaults to a `plugins` directory
+      alongside the Flux binary in $RUNNER_TOOL_CACHE.
+    required: false
   bindir:
     description: "Alternative location for the Flux binary, defaults to path relative to $RUNNER_TOOL_CACHE."
     required: false
   token:
     description: "Token used to authenticate against the GitHub.com API."
     required: false
+outputs:
+  plugin-dir:
+    description: >
+      Directory where the plugins were installed by the action.
+    value: ${{ steps.set-outputs.outputs.plugin-dir }}
 runs:
   using: composite
   steps:
     - name: "Download the binary to the runner's cache dir"
       shell: bash
+      id: setup-flux-bin
       env:
         VERSION: "${{ inputs.version }}"
         FLUX_TOOL_DIR: "${{ inputs.bindir }}"
@@ -42,11 +61,13 @@ runs:
         if [[ $VERSION = v* ]]; then
           VERSION="${VERSION:1}"
         fi
+        echo "installed-flux-version=$VERSION" >> "$GITHUB_OUTPUT"
 
         OS=$(echo "${RUNNER_OS}" | tr '[:upper:]' '[:lower:]')
         if [[ "$OS" == "macos" ]]; then
           OS="darwin"
         fi
+        echo "os=$OS" >> "$GITHUB_OUTPUT"
 
         ARCH=$(echo "${RUNNER_ARCH}" | tr '[:upper:]' '[:lower:]')
         if [[ "$ARCH" == "x64" ]]; then
@@ -54,6 +75,7 @@ runs:
         elif [[ "$ARCH" == "x86" ]]; then
           ARCH="386"
         fi
+        echo "arch=$ARCH" >> "$GITHUB_OUTPUT"
 
         FLUX_EXEC_FILE="flux"
         if [[ "$OS" == "windows" ]]; then
@@ -63,7 +85,7 @@ runs:
         if [[ -z "$FLUX_TOOL_DIR" ]]; then
           FLUX_TOOL_DIR="${RUNNER_TOOL_CACHE}/flux2/${VERSION}/${OS}/${ARCH}"
         fi
-        if [[ ! -x "$FLUX_TOOL_DIR/FLUX_EXEC_FILE" ]]; then
+        if [[ ! -x "$FLUX_TOOL_DIR/$FLUX_EXEC_FILE" ]]; then
           DL_DIR="$(mktemp -dt flux2-XXXXXX)"
           trap 'rm -rf $DL_DIR' EXIT
 
@@ -146,3 +168,63 @@ runs:
       shell: bash
       run: |
         flux -v
+
+    - name: "Plugin support gate"
+      id: plugin-support-gate
+      shell: bash
+      if: inputs.plugins != ''
+      run: |
+        flux_version="$(flux -v 2>/dev/null | awk '{print $3}')"
+        if flux plugin --help >/dev/null 2>&1; then
+          echo "plugin-support=yes" >> "$GITHUB_OUTPUT"
+          exit 0
+        else
+          echo "plugin-support=no" >> "$GITHUB_OUTPUT"
+          msg="Installed Flux version ${flux_version:-unknown} does not support plugins; need >= 2.9.0. Requested plugins cannot be installed."
+          echo "::error title=Unsupported Flux version::$msg"
+          echo "> [!CAUTION]" >> $GITHUB_STEP_SUMMARY
+          echo "> $msg" >> $GITHUB_STEP_SUMMARY
+          exit 1
+        fi
+
+    - name: "Setup Plugins Dir"
+      shell: bash
+      if: steps.plugin-support-gate.outputs.plugin-support == 'yes'
+      env:
+        FLUXCD_PLUGINS: ${{ inputs.plugin-dir }}
+        VERSION: ${{ steps.setup-flux-bin.outputs.installed-flux-version }}
+        OS: ${{ steps.setup-flux-bin.outputs.os }}
+        ARCH: ${{ steps.setup-flux-bin.outputs.arch }}
+      run: |
+        # Use a default plugin directory when plugin-dir was not provided.
+        if [[ -z "$FLUXCD_PLUGINS" ]]; then
+          FLUXCD_PLUGINS="${RUNNER_TOOL_CACHE}/flux2/${VERSION}/${OS}/${ARCH}/plugins/"
+        fi
+
+        # Export it so subsequent steps can discover the installed plugins.
+        echo "FLUXCD_PLUGINS=$FLUXCD_PLUGINS" >> "$GITHUB_ENV"
+
+        # Create the directory if it does not exist.
+        mkdir -p "$FLUXCD_PLUGINS"
+
+    - name: "Install Plugins"
+      shell: bash
+      id: install-plugins
+      if: steps.plugin-support-gate.outputs.plugin-support == 'yes'
+      env:
+        PLUGINS: ${{ inputs.plugins }}
+      run: |
+        echo "$PLUGINS" | while read -r PLUGIN; do
+          trimmed="${PLUGIN//[[:space:]]/}"
+          if [[ -n "$trimmed" ]]; then
+            echo Installing: "$PLUGIN"
+            flux plugin install "$PLUGIN"
+          fi
+        done
+
+    - name: "Set Output"
+      id: set-outputs
+      if: steps.plugin-support-gate.outputs.plugin-support == 'yes'
+      shell: bash
+      run: |
+        echo "plugin-dir=$FLUXCD_PLUGINS" >> "$GITHUB_OUTPUT"