Add requirements.txt file for Python dependencies (backport #40)

.github/actions/install_python_packages/action.yml

@@ -4,7 +4,12 @@ description: 'Install specified Python packages in a virtual environment'
 inputs:
   packages:
     description: 'A space-separated list of Python packages to install.'
-    required: true
+    required: false
+    default: ''
+  requirements-file:
+    description: 'Path to a requirements.txt file listing Python packages to install.'
+    required: false
+    default: ''
   python-version:
     description: 'The Python version to use (e.g., 3.12).'
     required: true
@@ -36,5 +41,12 @@ runs:
 
     - name: Install Python packages
       run: |
-        pip install ${{ inputs.packages }}
+        if [ -n "${{ inputs.requirements-file }}" ]; then
+          pip install -r ${{ inputs.requirements-file }}
+        fi
+
+        if [ -n "${{ inputs.packages }}" ]; then
+          pip install ${{ inputs.packages }}
+        fi
+
       shell: bash

.github/workflows/reusable-ci.yml

@@ -45,7 +45,7 @@ jobs:
       - name: Install required python packages
         uses: ./.github/actions/install_python_packages
         with:
-          packages: "catkin_pkg lark-parser empy colcon-common-extensions"
+          requirements-file: "${{ github.workspace }}/requirements.txt"
           python-version: ${{ inputs.python-version }}
           use-sudo: "true"
 

README.md

@@ -18,7 +18,7 @@ sudo apt install -y rsync pip git gcc-arm-none-eabi cmake
 This component needs `colcon` and other Python 3 packages in order to build micro-ROS packages:
 
 ```bash
-pip3 install catkin_pkg lark-parser empy colcon-common-extensions
+pip3 install -r requirements.txt
 ```
 
 ## Usage

requirements.txt

@@ -0,0 +1,4 @@
+catkin_pkg
+lark-parser
+empy
+colcon-common-extensions