Image-cleaner: mount docker dir instead of socket

BinderHub/K8s has a long standing bug where sometimes the docker socket is created as a host directory.

Author: manics

helm-chart/binderhub/schema.yaml

@@ -495,16 +495,20 @@ properties:
       host:
         type: object
         additionalProperties: false
-        required: [dockerSocket, dockerLibDir]
+        required: [dockerSocketDir, dockerSocketName, dockerLibDir]
         properties:
           enabled:
             type: boolean
             description: |
               DEPRECATED: use imageCleaner.enabled if the cleaner shall not used.
-          dockerSocket:
+          dockerSocketDir:
             type: string
             description: |
-              TODO
+              Host directory containing the docker socket.
+          dockerSocketName:
+            type: string
+            description: |
+              Filename of the docker socket.
           dockerLibDir:
             type: string
             description: |

helm-chart/binderhub/templates/image-cleaner.yaml

@@ -49,8 +49,8 @@ spec:
         volumeMounts:
         - name: storage-{{ $builderName }}
           mountPath: /var/lib/{{ $builderName }}
-        - name: socket-{{ $builderName }}
-          mountPath: /var/run/docker.sock
+        - name: socketdir-{{ $builderName }}
+          mountPath: /var/run
         env:
         {{- if .Values.imageCleaner.cordon }}
         - name: DOCKER_IMAGE_CLEANER_NODE_NAME
@@ -68,6 +68,8 @@ spec:
           value: {{ .Values.imageCleaner.imageGCThresholdHigh | quote }}
         - name: DOCKER_IMAGE_CLEANER_THRESHOLD_LOW
           value: {{ .Values.imageCleaner.imageGCThresholdLow | quote }}
+        - name: DOCKER_HOST
+          value: unix:///var/run/{{ eq $builderName "host" | ternary .Values.imageCleaner.host.dockerSocketName $builder.hostSocketName }}
         {{- with .Values.imageCleaner.extraEnv }}
         {{- include "jupyterhub.extraEnv" . | nindent 8 }}
         {{- end }}
@@ -77,19 +79,19 @@ spec:
       - name: storage-host
         hostPath:
           path: {{ .Values.imageCleaner.host.dockerLibDir }}
-      - name: socket-host
+      - name: socketdir-host
         hostPath:
-          path: {{ .Values.imageCleaner.host.dockerSocket }}
-          type: Socket
+          path: {{ .Values.imageCleaner.host.dockerSocketDir }}
+          type: Directory
       {{- end }}
       {{- if or (eq $builderName "dind") (eq $builderName "pink") }}
       - name: storage-{{ $builderName }}
         hostPath:
           path: {{ eq $builderName "dind" | ternary $builder.hostLibDir $builder.hostStorageDir }}
-          type: DirectoryOrCreate
-      - name: socket-{{ $builderName }}
+          type: Directory
+      - name: socketdir-{{ $builderName }}
         hostPath:
-          path: {{ $builder.hostSocketDir }}/{{ $builder.hostSocketName }}
-          type: Socket
+          path: {{ $builder.hostSocketDir }}
+          type: Directory
       {{- end }}
 {{- end }}

helm-chart/binderhub/values.yaml

@@ -335,10 +335,11 @@ imageCleaner:
   # cull images until it drops below 60%
   imageGCThresholdHigh: 80
   imageGCThresholdLow: 60
-  # cull images on the host docker as well as dind
+  # cull images on the host docker
   # configuration to use if `imageBuilderType: host` is configured
   host:
-    dockerSocket: /var/run/docker.sock
+    dockerSocketDir: /var/run
+    dockerSocketName: docker.sock
     dockerLibDir: /var/lib/docker
 
 ingress:

tools/templates/lint-and-validate-values.yaml

@@ -128,7 +128,8 @@ imageCleaner:
   imageGCThresholdHigh: 2
   imageGCThresholdLow: 1
   host:
-    dockerSocket: /var/run/docker.sock
+    dockerSocketDir: /var/run
+    dockerSocketName: docker.sock
     dockerLibDir: /var/lib/docker
 
 ingress: