Docker tag

Author: mattolenik

.github/workflows/release.yml

@@ -15,6 +15,9 @@ jobs:
         uses: actions/setup-go@v2
         with:
           go-version: 1.15.x
+      - name: Get release version
+        id: get_version
+        run: echo ::set-env name=RELEASE_VERSION::$(echo ${GITHUB_REF:10})
       - name: Checkout code
         uses: actions/checkout@v2
       - name: Build
@@ -31,3 +34,4 @@ jobs:
           name: ${{ secrets.DOCKER_USERNAME }}/cloudflare-ddns-client
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}
+          tags: "latest,${{ env.RELEASE_VERSION }}"