automate release

.github/workflows/release.yaml

@@ -0,0 +1,39 @@
+name: ytld-sub release
+on:
+  push:
+    # publish only when pushed to master
+    branches:
+      - master
+
+jobs:
+  release:
+    name: release
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - name: Get release version
+        run:
+          date +'%Y.%m.%d' >> $DATE
+          git rev-list --count HEAD --since="$(DATE) 00:00:00" >> $DATE_COMMIT_COUNT
+          
+          if [ "$(DATE_COMMIT_COUNT)" = "0" ]; then
+            echo "$DATE" >> $PYPI_VERSION
+          else
+            echo "$(DATE).post$(DATE_COMMIT_COUNT)" >> $PYPI_VERSION
+          endif
+
+      - name: Create Release
+        id: create_release
+        uses: actions/create-release@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          tag_name: $(PYPI_VERSION)
+          release_name: ytdl-sub $(PYPI_VERSION)
+          body: |
+            See https://github.com/jmbannon/ytdl-sub#installation for installation steps
+          draft: false
+          prerelease: false