build: add GitHub Action for pushing to docker hub (#15)

* add action until extracting version

* remove extra quotes

* enable extended regex

* test if the first grep is working

* use Perl-compatible regex

* add build and push step

.github/workflows/publish.yaml

@@ -0,0 +1,48 @@
+name: Publish
+
+on:
+  push:
+    branches:
+      - main
+    path:
+      - pyproject.toml
+
+jobs:
+  push_to_registry:
+    name: Push Docker image to Docker Hub
+    runs-on: ubuntu-latest
+    permissions:
+      packages: write
+      contents: read
+      attestations: write
+      id-token: write
+
+    steps:
+      - name: Check out the repo
+        uses: actions/checkout@v4
+
+      - name: Log in to Docker Hub
+        uses: docker/login-action@f4ef78c080cd8ba55a85445d5b36e214a81df20a
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+
+      - name: Extract version for tagging
+        id: version
+        run: echo "version=$(grep -m 1 version pyproject.toml | grep -P '\d.\d.\d' -o)" >> $GITHUB_OUTPUT
+
+      - name: Build and push Docker image
+        id: push
+        uses: docker/build-push-action@3b5e8027fcad23fda98b2e3ac259d8d67585f671
+        with:
+          context: .
+          file: ./Dockerfile
+          push: true
+          tags: jljl1337/testpod:latest,jljl1337/testpod:${{ steps.version.outputs.version }}
+
+      - name: Generate artifact attestation
+        uses: actions/attest-build-provenance@v2
+        with:
+          subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          subject-digest: ${{ steps.push.outputs.digest }}
+          push-to-registry: true