Add support for --allow-downgrades flag in init container

Co-authored-by: andyzhangx <[email protected]>

Author: Copilot

README.md

@@ -47,6 +47,11 @@ This option does not depend on cloud provider config file, supports cross subscr
 > If you want to install a lower version of blobfuse2 than the current version, you can add ` --allow-downgrades` to the `BLOBFUSE2_VERSION` value, e.g.
 > ```console
 > kubectl patch daemonset csi-blob-node -n kube-system -p '{"spec":{"template":{"spec":{"initContainers":[{"env":[{"name":"INSTALL_BLOBFUSE2","value":"true"},{"name":"BLOBFUSE2_VERSION","value":"2.3.0 --allow-downgrades"}],"name":"install-blobfuse-proxy"}]}}}}'
+> ```
+>
+> Alternatively, when using Helm charts, you can use the dedicated `allowBlobfuse2Downgrades` parameter for cleaner configuration:
+> ```console
+> helm upgrade --set node.blobfuseProxy.blobfuse2Version="2.3.0" --set node.blobfuseProxy.allowBlobfuse2Downgrades=true blob-csi-driver charts/latest/blob-csi-driver
 > ```
 
  - install by [helm charts](./charts)

charts/latest/blob-csi-driver/templates/csi-blob-node.yaml

@@ -88,10 +88,14 @@ spec:
               value: "{{ .Values.node.blobfuseProxy.installBlobfuse }}"
             - name: BLOBFUSE_VERSION
               value: "{{ .Values.node.blobfuseProxy.blobfuseVersion }}"
+            - name: ALLOW_BLOBFUSE_DOWNGRADES
+              value: "{{ .Values.node.blobfuseProxy.allowBlobfuseDowngrades }}"
             - name: INSTALL_BLOBFUSE2
               value: "{{ .Values.node.blobfuseProxy.installBlobfuse2 }}"
             - name: BLOBFUSE2_VERSION
               value: "{{ .Values.node.blobfuseProxy.blobfuse2Version }}"
+            - name: ALLOW_BLOBFUSE2_DOWNGRADES
+              value: "{{ .Values.node.blobfuseProxy.allowBlobfuse2Downgrades }}"
             - name: INSTALL_BLOBFUSE_PROXY
               value: "{{ .Values.node.enableBlobfuseProxy }}"
             - name: SET_MAX_OPEN_FILE_NUM

charts/latest/blob-csi-driver/values.yaml

@@ -122,8 +122,10 @@ node:
   blobfuseProxy:
     installBlobfuse: false
     blobfuseVersion: "1.4.5"
+    allowBlobfuseDowngrades: false
     installBlobfuse2: true
     blobfuse2Version: "2.4.1"
+    allowBlobfuse2Downgrades: false
     setMaxOpenFileNum: true
     maxOpenFileNum: "9000000"
     disableUpdateDB: true

pkg/blobfuse-proxy/install-proxy.sh

@@ -54,7 +54,11 @@ then
       echo "install blobfuse with latest version"
       pkg_list="${pkg_list} blobfuse"
     else
-      pkg_list="${pkg_list} blobfuse=${BLOBFUSE_VERSION}"
+      blobfuse_install_str="blobfuse=${BLOBFUSE_VERSION}"
+      if [ "${ALLOW_BLOBFUSE_DOWNGRADES}" = "true" ]; then
+        blobfuse_install_str="${blobfuse_install_str} --allow-downgrades"
+      fi
+      pkg_list="${pkg_list} ${blobfuse_install_str}"
     fi
   fi
 
@@ -73,7 +77,11 @@ then
       echo "install blobfuse2 with latest version"
       pkg_list="${pkg_list} blobfuse2"
     else
-      pkg_list="${pkg_list} blobfuse2=${BLOBFUSE2_VERSION}"
+      blobfuse2_install_str="blobfuse2=${BLOBFUSE2_VERSION}"
+      if [ "${ALLOW_BLOBFUSE2_DOWNGRADES}" = "true" ]; then
+        blobfuse2_install_str="${blobfuse2_install_str} --allow-downgrades"
+      fi
+      pkg_list="${pkg_list} ${blobfuse2_install_str}"
     fi
   fi