ci: Add publish-main workflow

This is based on the following commit with a few changes:
https://github.com/JonathonReinhart/scuba/blob/b086413404/.github/workflows/publish-main.yml

- pip install setuptools wheel
- apt install scons
- CC -> BOOTLOADER_CC

TODO: Un-comment branches: main

.github/workflows/publish-main.yml

@@ -0,0 +1,45 @@
+name: Upload to Test PyPI
+
+# On every push to main, push to Test PyPI
+on:
+  push:
+    #branches:
+    #  - main
+
+# TODO: De-duplicate with python-publish-release.yml
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v3
+
+    # https://github.com/actions/checkout#fetch-all-history-for-all-tags-and-branches
+    - name: Unshallow checkout
+      run: git fetch --prune --unshallow
+
+    - name: Set up Python
+      uses: actions/setup-python@v4
+      with:
+        python-version: '3.x'
+
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install setuptools wheel twine
+
+        sudo apt-get update
+        sudo apt-get install -y musl-tools scons
+
+    - name: Build
+      env:
+        BOOTLOADER_CC: /usr/bin/musl-gcc
+        CI_VERSION_BUILD_NUMBER: ${{ github.run_id }}
+      run: python setup.py sdist bdist_wheel
+
+    - name: Publish
+      env:
+        TWINE_USERNAME: ${{ secrets.PYPI_TEST_USERNAME }}
+        TWINE_PASSWORD: ${{ secrets.PYPI_TEST_PASSWORD }}
+      run: twine upload --repository-url https://test.pypi.org/legacy/ dist/*

setup.py

@@ -14,13 +14,13 @@
 def get_dynamic_version():
     import staticx.version
 
-    # Travis builds
-    # If we're not building for a tag, then append the build number
-    build_num = os.getenv('TRAVIS_BUILD_NUMBER')
-    build_tag = os.getenv('TRAVIS_TAG')
-    if (not build_tag) and (build_num != None):
+    # CI builds
+    # If CI_VERSION_BUILD_NUMBER is set, append that to the base version
+    build_num = os.getenv("CI_VERSION_BUILD_NUMBER")
+    if build_num:
         return f'{staticx.version.BASE_VERSION}.{build_num}'
 
+    # Otherwise, use the auto-versioning
     return staticx.version.__version__