Add docker build

.github/workflows/docker-build-latest.yml

@@ -0,0 +1,41 @@
+name: Docker build latest
+on:
+  push:
+    branches:
+      - master
+
+env:
+  IMAGE_NAME: outsideopen/opencanary
+  TAG: latest
+
+jobs:
+  build-latest:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+
+      - name: Login to DockerHub
+        uses: docker/login-action@v2
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ github.token }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v3
+        with:
+          context: .
+          file: Dockerfile.latest
+          platforms: linux/amd64,linux/arm64
+          push: true
+          cache-from: type=registry,ref=ghcr.io/${{ github.repository }}:${{ env.TAG }}
+          cache-to: type=inline
+          tags: ghcr.io/${{ github.repository }}:${{ env.TAG }}
+