Use BuildX's cache mount for caching.

.github/workflows/docker-build.yml

@@ -26,15 +26,6 @@ jobs:
         with:
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}
-      - name: Get hash of latest image
-        run: docker pull golang:alpine && docker inspect --format='{{index .RepoDigests 0}}' golang:alpine > dockerhash.txt
-      - name: cache docker cache
-        uses: actions/cache@v2.1.2
-        with:
-          path: ${{ github.workspace }}/cache
-          key: ${{ runner.os }}-docker-${{ hashFiles('**/go.mod') }}-${{ hashFiles('**/go.sum') }}-${{ hashFiles('**/dockerhash.txt') }}
-          restore-keys: |
-            ${{ runner.os }}-docker-
       - name: Build and push
         uses: docker/build-push-action@v2
         with:
@@ -43,5 +34,5 @@ jobs:
           platforms: linux/386,linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64/v8
           push: true
           tags: 1337kavin/ytproxy:latest
-          cache-from: type=local,src=cache
-          cache-to: type=local,dest=cache
+          cache-from: type=gha
+          cache-to: type=gha,mode=max

Dockerfile

@@ -4,7 +4,8 @@ WORKDIR /app/
 
 COPY . .
 
-RUN go build -ldflags "-s -w" main.go
+RUN  --mount=type=cache,target=/root/.cache/go-build \
+    go build -ldflags "-s -w" main.go
 
 FROM alpine:edge