Merge f5c610f into 5b7450f

reana_commons/config.py

@@ -127,3 +127,6 @@
 
 INTERACTIVE_SESSION_TYPES = ['jupyter']
 """List of supported interactive systems."""
+
+REANA_STORAGE_BACKEND = os.getenv('REANA_STORAGE_BACKEND', 'LOCAL')
+"""Storage backend deployed in current REANA cluster."""

reana_commons/k8s/volumes.py

@@ -0,0 +1,87 @@
+# -*- coding: utf-8 -*-
+#
+# This file is part of REANA.
+# Copyright (C) 2019 CERN.
+#
+# REANA is free software; you can redistribute it and/or modify it
+# under the terms of the MIT License; see LICENSE file for more details.
+
+"""REANA Kubernetes volumes."""
+
+import os
+
+import json
+
+from reana_commons.config import REANA_STORAGE_BACKEND
+
+REANA_SHARED_VOLUME_NAME = "reana-shared-volume"
+REANA_CEPHFS_CLAIM_NAME = "manila-cephfs-pvc"
+
+
+def get_k8s_cephfs_volume():
+    """Return k8s CephFS volume template.
+
+    :returns: k8s CephFS volume spec as a dictionary.
+    """
+    return {
+        "name": REANA_SHARED_VOLUME_NAME,
+        "persistentVolumeClaim": {
+            "claimName": REANA_CEPHFS_CLAIM_NAME
+        },
+        "readOnly": "false"
+    }
+
+
+def get_k8s_cvmfs_volume(repository):
+    """Render k8s CVMFS volume template.
+
+    :param repository: CVMFS repository to be mounted.
+    :returns: k8s CVMFS volume spec as a dictionary.
+    """
+    return {
+        "name": "{}-cvmfs-volume".format(repository),
+        "persistentVolumeClaim": {
+            "claimName": "csi-cvmfs-{}-pvc".format(repository)
+        },
+        "readOnly": "true"
+    }
+
+
+def get_k8s_hostpath_volume(root_path):
+    """Render k8s HostPath volume template.
+
+    :param root_path: Root path in the host machine to be mounted.
+    :returns: k8s HostPath spec as a dictionary.
+    """
+    return {
+        "name": REANA_SHARED_VOLUME_NAME,
+        "hostPath": {
+            "path": root_path
+        }
+    }
+
+
+def get_shared_volume(workflow_workspace, shared_volume_root):
+    """Get shared CephFS/hostPath volume to a given job spec.
+
+    :param workflow_workspace: Absolute path to the job's workflow workspace.
+    :param shared_volume_root: Root path in the underlying storage backend.
+    :returns: Tuple consisting of the Kubernetes volumeMount and the volume.
+    """
+    workflow_workspace_relative_to_owner = workflow_workspace
+    if os.path.isabs(workflow_workspace):
+        workflow_workspace_relative_to_owner = \
+            os.path.relpath(workflow_workspace, shared_volume_root)
+    mount_path = os.path.join(shared_volume_root,
+                              workflow_workspace_relative_to_owner)
+    volume_mount = {
+        "name": REANA_SHARED_VOLUME_NAME,
+        "mountPath": mount_path,
+        "subPath": workflow_workspace_relative_to_owner}
+
+    if REANA_STORAGE_BACKEND == "CEPHFS":
+        volume = get_k8s_cephfs_volume()
+    else:
+        volume = get_k8s_hostpath_volume(shared_volume_root)
+
+    return volume_mount, volume