Add build and push action

Author: ChrisLovering

.github/workflows/build_and_push.yml

@@ -0,0 +1,44 @@
+name: Build and push to GHCR
+
+on:
+  push:
+    branches:
+      - deployment
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Create a SHA tag
+        id: sha_tag
+        run: |
+          tag=$(cut -c 1-7 <<< $GITHUB_SHA)
+          echo "::set-output name=tag::$tag"
+
+      - name: Checkout code
+        uses: actions/checkout@v3
+      - name: Setup Docker BuildX
+        uses: docker/setup-buildx-action@v2
+
+      - name: Login to GHCR
+        uses: docker/login-action@v2
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ github.token }}
+      
+      - name: Build and push
+        uses: docker/build-push-action@v3
+        with:
+          context: .
+          file: ./Dockerfile
+          push: true
+          cache-from: type=repository,ref=ghcr.io/python-discord/logviewer:latest
+          cache-to: type=inline
+          tags: |
+            ghcr.io/python-discord/logviewer:latest
+            ghcr.io/python-discord/logviewer:${{ steps.sha_tag.outputs.tag }}