cluster: allow to mount volumes in agent container (#299)

Fixes #299

config/operator/crd/bases/scylla.scylladb.com_scyllaclusters.yaml

@@ -143,6 +143,34 @@ spec:
                             description: 'Requests describes the minimum amount of compute resources required. If Requests is omitted for a container, it defaults to Limits if that is explicitly specified, otherwise to an implementation-defined value. More info: https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container/'
                             type: object
                         type: object
+                      agentVolumeMounts:
+                        description: AgentVolumeMounts to be added to Agent container.
+                        items:
+                          description: VolumeMount describes a mounting of a Volume within a container.
+                          properties:
+                            mountPath:
+                              description: Path within the container at which the volume should be mounted.  Must not contain ':'.
+                              type: string
+                            mountPropagation:
+                              description: mountPropagation determines how mounts are propagated from the host to container and the other way around. When not set, MountPropagationNone is used. This field is beta in 1.10.
+                              type: string
+                            name:
+                              description: This must match the Name of a Volume.
+                              type: string
+                            readOnly:
+                              description: Mounted read-only if true, read-write otherwise (false or unspecified). Defaults to false.
+                              type: boolean
+                            subPath:
+                              description: Path within the volume from which the container's volume should be mounted. Defaults to "" (volume's root).
+                              type: string
+                            subPathExpr:
+                              description: Expanded path within the volume from which the container's volume should be mounted. Behaves similarly to SubPath but environment variable references $(VAR_NAME) are expanded using the container's environment. Defaults to "" (volume's root). SubPathExpr and SubPath are mutually exclusive.
+                              type: string
+                          required:
+                          - mountPath
+                          - name
+                          type: object
+                        type: array
                       members:
                         description: Members is the number of Scylla instances in this rack.
                         format: int32
@@ -582,7 +610,7 @@ spec:
                           type: object
                         type: array
                       volumes:
-                        description: Volumes added to Scylla container.
+                        description: Volumes added to Scylla Pod.
                         items:
                           description: Volume represents a named volume in a pod that may be accessed by any container in the pod.
                           properties:

examples/common/operator.yaml

@@ -158,6 +158,34 @@ spec:
                             description: 'Requests describes the minimum amount of compute resources required. If Requests is omitted for a container, it defaults to Limits if that is explicitly specified, otherwise to an implementation-defined value. More info: https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container/'
                             type: object
                         type: object
+                      agentVolumeMounts:
+                        description: AgentVolumeMounts to be added to Agent container.
+                        items:
+                          description: VolumeMount describes a mounting of a Volume within a container.
+                          properties:
+                            mountPath:
+                              description: Path within the container at which the volume should be mounted.  Must not contain ':'.
+                              type: string
+                            mountPropagation:
+                              description: mountPropagation determines how mounts are propagated from the host to container and the other way around. When not set, MountPropagationNone is used. This field is beta in 1.10.
+                              type: string
+                            name:
+                              description: This must match the Name of a Volume.
+                              type: string
+                            readOnly:
+                              description: Mounted read-only if true, read-write otherwise (false or unspecified). Defaults to false.
+                              type: boolean
+                            subPath:
+                              description: Path within the volume from which the container's volume should be mounted. Defaults to "" (volume's root).
+                              type: string
+                            subPathExpr:
+                              description: Expanded path within the volume from which the container's volume should be mounted. Behaves similarly to SubPath but environment variable references $(VAR_NAME) are expanded using the container's environment. Defaults to "" (volume's root). SubPathExpr and SubPath are mutually exclusive.
+                              type: string
+                          required:
+                          - mountPath
+                          - name
+                          type: object
+                        type: array
                       members:
                         description: Members is the number of Scylla instances in this rack.
                         format: int32
@@ -597,7 +625,7 @@ spec:
                           type: object
                         type: array
                       volumes:
-                        description: Volumes added to Scylla container.
+                        description: Volumes added to Scylla Pod.
                         items:
                           description: Volume represents a named volume in a pod that may be accessed by any container in the pod.
                           properties:

examples/generic/cluster.yaml

@@ -104,6 +104,6 @@ spec:
           - name: coredumpfs
             hostPath:
               path: /tmp/coredumps
-        volumeMounts:
+        agentVolumeMounts:
           - mountPath: /tmp/coredumps
             name: coredumpfs

pkg/api/v1alpha1/cluster_types.go

@@ -196,10 +196,12 @@ type RackSpec struct {
 	Resources corev1.ResourceRequirements `json:"resources"`
 	// AgentResources which Agent container will use.
 	AgentResources corev1.ResourceRequirements `json:"agentResources,omitempty"`
-	// Volumes added to Scylla container.
-	Volumes []corev1.Volume `json:"volumes,omitempty" patchStrategy:"merge,retainKeys" patchMergeKey:"name" protobuf:"bytes,1,rep,name=volumes"`
+	// Volumes added to Scylla Pod.
+	Volumes []corev1.Volume `json:"volumes,omitempty" patchStrategy:"merge,retainKeys" patchMergeKey:"name"`
 	// VolumeMounts to be added to Scylla container.
-	VolumeMounts []corev1.VolumeMount `json:"volumeMounts,omitempty" patchStrategy:"merge" patchMergeKey:"mountPath" protobuf:"bytes,9,rep,name=volumeMounts"`
+	VolumeMounts []corev1.VolumeMount `json:"volumeMounts,omitempty" patchStrategy:"merge" patchMergeKey:"mountPath"`
+	// AgentVolumeMounts to be added to Agent container.
+	AgentVolumeMounts []corev1.VolumeMount `json:"agentVolumeMounts,omitempty" patchStrategy:"merge" patchMergeKey:"mountPath"`
 	// Scylla config map name to customize scylla.yaml
 	ScyllaConfig string `json:"scyllaConfig"`
 	// Scylla config map name to customize scylla manager agent

pkg/controllers/cluster/resource/resource.go

@@ -437,7 +437,7 @@ func sysctlInitContainer(sysctls []string) *corev1.Container {
 }
 
 func agentContainer(r scyllav1alpha1.RackSpec, c *scyllav1alpha1.ScyllaCluster) corev1.Container {
-	return corev1.Container{
+	cnt := corev1.Container{
 		Name:            "scylla-manager-agent",
 		Image:           agentImageForCluster(c),
 		ImagePullPolicy: "IfNotPresent",
@@ -466,6 +466,12 @@ func agentContainer(r scyllav1alpha1.RackSpec, c *scyllav1alpha1.ScyllaCluster)
 		},
 		Resources: r.AgentResources,
 	}
+
+	for _, vm := range r.AgentVolumeMounts {
+		cnt.VolumeMounts = append(cnt.VolumeMounts, *vm.DeepCopy())
+	}
+
+	return cnt
 }
 
 func ImageForCluster(c *scyllav1alpha1.ScyllaCluster) string {