Fix install-dir when using the default

Author: marcofranssen

installer-action/action.yaml

@@ -12,20 +12,24 @@ inputs:
   install-dir:
     description: 'Where to install the fatt binary'
     required: false
-    default: '$HOME/.fatt/bin'
+    default: "$HOME/.fatt/bin"
 runs:
   using: 'composite'
   steps:
+    # To expand the $HOME environment variable when setting the INSTALL_PATH variable
+    # this way of adding to the GITHUB_ENV is required. Via yaml syntax 'env: …' will
+    # not work and result in a relative install-dir like
+    # /home/runner/work/slsa-workflow-examples/slsa-workflow-examples/$HOME/.fatt/bin.
+    # where you would expect /home/runner/.fatt/bin
+    - shell: bash
+      run: echo "INSTALL_PATH=${{ inputs.install-dir }}" >> $GITHUB_ENV
     - shell: bash
       run: $GITHUB_ACTION_PATH/install.sh
       env:
         VERSION: ${{ inputs.fatt-release }}
-        INSTALL_PATH: ${{ inputs.install-dir }}
     - if: ${{ runner.os == 'Linux' || runner.os == 'macOS' }}
-      run: |
-        echo "${{ inputs.install-dir }}" >> $GITHUB_PATH
-        echo "binary installed at $(command -v fatt)"
+      run: echo "${{ inputs.install-dir }}" >> $GITHUB_PATH
       shell: bash
     - if: ${{ runner.os == 'Windows' }}
-      run:  echo "${{ inputs.install-dir }}" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
+      run: echo "${{ inputs.install-dir }}" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
       shell: pwsh

installer-action/install.sh

@@ -17,9 +17,9 @@ set -e
 GITHUB_API=${GITHUB_API:-'https://api.github.com'}
 
 # default to relative path if INSTALL_PATH is not set
-INSTALL_PATH=${INSTALL_PATH:-./.fatt/bin}
+# INSTALL_PATH=${INSTALL_PATH:-./.fatt/bin}
 mkdir -p "${INSTALL_PATH}"
-INSTALL_PATH="$(realpath "${INSTALL_PATH}")"
+# INSTALL_PATH="$(realpath "${INSTALL_PATH}")"
 
 VERSION="${VERSION:-v0.2.0-rc}"
 RELEASE="https://github.com/philips-labs/fatt/releases/download/${VERSION}"
@@ -81,7 +81,7 @@ DOWNLOAD="${RELEASE}/${ARCHIVE}"
 log_info "Installing ${BINARY} (${OS}/${ARCH}) at ${INSTALL_PATH}"
 
 trap "popd >/dev/null" EXIT
-pushd "$INSTALL_PATH" >/dev/null || exit
+pushd "${INSTALL_PATH}" || exit
 
 download "${ARCHIVE}" "${DOWNLOAD}"