Don't use build cache if version changed or manually overwritten

.gitlab-ci.yml

@@ -5,20 +5,35 @@ docker-build-master:
   services:
     - docker:dind
   variables:
-    DOCKER_TLS_CERTDIR: ""
+    LAST_VERSION_FILE: .last_version
+  cache:
+    paths:
+      - $LAST_VERSION_FILE
   before_script:
     - apk add --no-cache jq curl
     - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" $CI_REGISTRY
   script:
-    - FULL_VERSION=$(curl --silent "https://aur.archlinux.org/rpc.php?type=info&arg=nginx-quic" | jq -r '.results.Version') && VERSION=${FULL_VERSION%-*} && export VERSION
+    - FULL_VERSION=$(curl --silent "https://aur.archlinux.org/rpc.php?type=info&arg=nginx-quic" | jq -r '.results.Version') && VERSION=${FULL_VERSION%-*} && export FULL_VERSION && export VERSION
+    - [[ -f "LAST_VERSION_FILE ]] && export LAST_VERSION=$(<$LAST_VERSION_FILE)
+    - if [[ -n $LAST_VERSION && $LAST_VERSION != $FULL_VERSION ]]; then export CI_USE_CACHE=false; fi
+    - params=(); if [[ $CI_USE_CACHE == true ]]; then params+=(--cache-from "${CI_REGISTRY_IMAGE}:latest"); else params+=(--no-cache) ; fi && export params
+
     - docker pull "${CI_REGISTRY_IMAGE}:latest" # https://gitlab.com/gitlab-org/gitlab-foss/-/issues/17861#note_19140733
-    - docker build --pull --cache-from "${CI_REGISTRY_IMAGE}:latest" -t "${CI_REGISTRY_IMAGE}:latest" .
+    - docker build --pull "${params[@]}" -t "${CI_REGISTRY_IMAGE}:latest" .
+
     - docker tag "${CI_REGISTRY_IMAGE}:latest" "${CI_REGISTRY_IMAGE}:${VERSION}"
     - docker tag "${CI_REGISTRY_IMAGE}:latest" "${CI_REGISTRY_IMAGE}:archlinux"
     - docker tag "${CI_REGISTRY_IMAGE}:latest" "${CI_REGISTRY_IMAGE}:${VERSION}-archlinux"
+
     - docker push "${CI_REGISTRY_IMAGE}:latest"
     - docker push "${CI_REGISTRY_IMAGE}:archlinux"
     - docker push "${CI_REGISTRY_IMAGE}:latest"
     - docker push "${CI_REGISTRY_IMAGE}:archlinux"
+
+    - echo $FULL_VERSION > $LAST_VERSION_FILE
   only:
     - master
+  except:
+    changes:
+      - "README.md"
+      - ".gitlab-ci.yml"