Improve nfs-server to support multiple shares and options

With this we aim at making the nfs-server element capable of
deploying an arbitrary number of shares and to define for each
a list of clients allowed and the respective export options.

Change-Id: Ib056885c94c3bc475ed0e84237c83414795fc8e0

elements/cinder-volume-nfs/README.md

@@ -10,5 +10,5 @@ Configuration
         # a list of nfs shares, each item in the list should be an nfs
         # share address. (e.g 192.0.2.5:/mnt/state/var/lib/nfs_share)
 
-**NOTE:** make sure to use the 'nfs-client' element when building the
-compute nodes too.
+**NOTE:** if backing Cinder with NFS remember to use the 'nfs-client'
+element on the compute nodes as they will have to mount the NFS share too.

elements/nfs-client/install.d/51-nfs-utils

@@ -2,4 +2,4 @@
 set -eux
 set -o pipefail
 
-install-packages -m nfs-client nfs_utils_package
+install-packages -m nfs-client nfs_client_package

elements/nfs-client/pkg-map

@@ -1,16 +1,16 @@
 {
   "family": {
     "redhat": {
-      "nfs_utils_package": "nfs-utils"
+      "nfs_client_package": "nfs-utils"
     },
     "debian": {
-      "nfs_utils_package": "nfs-common"
+      "nfs_client_package": "nfs-client"
     },
     "suse": {
-      "nfs_utils_package": "nfs-client"
+      "nfs_client_package": "nfs-client"
     }
   },
   "default": {
-    "nfs_utils_package": "nfs-utils"
+    "nfs_client_package": "nfs-utils"
   }
 }

elements/nfs-server/README.md

@@ -1,9 +1,28 @@
-##nfs-server
+Installs and configures NFS server services.
 
-This element installs and configures nfs services for testing the
-cinder nfs backend in an environment where no nfs services are
-present (i.e. CI)
+When added to an image this element will, depending on the
+config data, create a number of NFS shares and export them to
+the given list of clients with respective options.
 
-When added to an image, this element creates a directory at
-/mnt/state/var/lib/nfs and shares it to each node on the
-overcloud.
+Shares are created in /mnt/state/var/lib/nfs
+
+Configuration
+-------------
+
+    nfs_server:
+      shares:
+      - name: share_name
+        clients:
+        - machine: machine_allowed
+          options: rw,async,no_root_squash
+
+**NOTE**:
+
+* `share_name` should be a valid POSIX dirname, special chars, spaces or
+use of quotes is not supported
+
+* share dir created on filesystem will be owned by root/root with mode 0770
+
+* `machine` is required, defines the list of allowed clients, can be repeated
+
+* `options` can be omitted the following are used: rw,async,no_root_squash

elements/nfs-server/install.d/68-nfs-server

@@ -1,4 +1,4 @@
 #!/bin/bash
 set -eu
 
-install-packages nfs-kernel-server
+install-packages -m nfs-server nfs_server_package

elements/nfs-server/os-apply-config/etc/exports

@@ -1,3 +1,3 @@
 {{#nfs_server.shares}}
-/mnt/state/var/lib/nfs {{.}}(rw,async,no_root_squash)
+/mnt/state/var/lib/nfs/{{name}}{{#clients}} {{machine}}({{#options}}{{.}}{{/options}}{{^options}}rw,async,no_root_squash{{/options}}){{/clients}}
 {{/nfs_server.shares}}

elements/nfs-server/os-refresh-config/post-configure.d/74-nfs-server

@@ -1,7 +1,27 @@
 #!/bin/bash
 set -eu
 
-[ -d /mnt/state/var/lib/nfs ] || install -d -m 0770 -o root -g root /mnt/state/var/lib/nfs
+# We want to create a dir for each export in /etc/exports and
+# allow valid POSIX paths only.
+for share in $(grep -oE '^/[a-zA-Z0-9._-/]+' /etc/exports); do
+    [ -d "$share" ] || install -d -m 0770 -o root -g root "$share"
+done
+
+# Yet exports(5) allows for # comments; unquoted paths without spaces;
+# unquoted paths with octal ascii sequences; double-quoted paths with spaces.
+# Parsing all formats correctly requires usage of some non trivial
+# code, which we decided to avoid for now.
+# Shall we decide to support that, the following code should do (thanks lxsli).
+#
+#CODE='import ast, os.path, re, sys
+#lines = sys.stdin.readlines()
+#matchers = [re.match("\"([^\"]+)\"|(\\S+)", line) for line in lines if not re.search("^\s*#", line)]
+#lines = [m.group(1) or m.group(2) for m in matchers]
+#paths = [ast.literal_eval("\"%s\"" % line) for line in lines]
+#paths = [path for path in paths if not os.path.isdir(path)]
+#print "\n".join(paths),'
+#cat /etc/exports | python -c "$CODE" | xargs -i install -d -m 0770 -o root -g root "{}
+
 os-svc-enable -n nfs-server
 os-svc-restart -n nfs-server
 exportfs -a -r -v

elements/nfs-server/pkg-map

@@ -0,0 +1,16 @@
+{
+  "family": {
+    "redhat": {
+      "nfs_server_package": "nfs-utils"
+    },
+    "debian": {
+      "nfs_server_package": "nfs-server"
+    },
+    "suse": {
+      "nfs_server_package": "nfs-kernel-server"
+    }
+  },
+  "default": {
+    "nfs_server_package": "nfs-utils"
+  }
+}