Add docker builder workflow (#4)

Author: Consek

.github/workflows/docker_builder.yml

@@ -0,0 +1,50 @@
+name: Build and Publish docker images
+
+on:
+  push:
+    branches:
+      - master
+    tags:
+      - 'v**'
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        component: ["frontend", "proxy", "backend"]
+        dockerhub_repo: ["consek"]
+    steps:
+      -
+        name: Checkout
+        uses: actions/checkout@v2
+      -
+        name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v3
+        with:
+          images: ${{ matrix.dockerhub_repo }}/${{ matrix.component }}
+          tags: |
+            type=semver,pattern={{version}}
+            type=semver,pattern={{raw}}
+            type=sha,format=long
+            latest
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+      -
+        name: Login to DockerHub
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+      -
+        name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          context: ${{ matrix.component }}/.
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          cache-from: ${{ matrix.dockerhub_repo }}/${{ matrix.component }}:sha-${{ github.sha }},${{ matrix.dockerhub_repo }}/${{ matrix.component }}:latest
+          cache-to: type=inline