Set up Docker publish to GHCR

.github/workflows/docker.yml

@@ -1,24 +1,42 @@
-name: Build Docker image
+name: Build and Publish Docker Image
 
 on:
   push:
   pull_request:
+  workflow_dispatch:
 
 jobs:
-  build:
+  build-publish:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v4
+      - name: Checkout repository
+        uses: actions/checkout@v4
 
-      - name: Build the Docker image
-        run: docker build . --tag mitmproxy-pretendo
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
 
-      - name: Save the Docker image
-        run: docker save mitmproxy-pretendo -o mitmproxy-pretendo.tar
+      - name: Log into the GitHub container registry
+        if: ${{ github.event != 'pull_request' && github.ref == 'refs/heads/main' }}
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract Docker metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ghcr.io/${{ github.repository }}
 
-      - name: Upload the Docker image
-        uses: actions/upload-artifact@v4
+      - name: Build and push Docker image
+        id: build-and-push
+        uses: docker/build-push-action@v5
         with:
-          name: mitmproxy-pretendo-docker-image-${{ github.sha }}
-          path: mitmproxy-pretendo.tar
+          context: .
+          push: ${{ github.event != 'pull_request' && github.ref == 'refs/heads/main' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max