Add: step to create /etc/fstab

3 files changed, 74 insertions, 0 deletions

diff --git a/vmdb/plugins/fstab.mdwn b/vmdb/plugins/fstab.mdwn
new file mode 100644
index 0000000..a2c8eef
--- /dev/null
+++ b/vmdb/plugins/fstab.mdwn
@@ -0,0 +1,12 @@
+Step: `fstab`
+-----------------------------------------------------------------------------
+
+Create `/etc/fstab` inside the the image.
+
+Step keys:
+
+* `fstab` — REQUIRED; value is the tag for the root filesystem.
+
+Example (in the .vmdb file):
+
+    - fstab: root
diff --git a/vmdb/plugins/fstab_plugin.py b/vmdb/plugins/fstab_plugin.py
new file mode 100644
index 0000000..da985bc
--- /dev/null
+++ b/vmdb/plugins/fstab_plugin.py
@@ -0,0 +1,61 @@
+# Copyright 2019 Antonio Terceiro
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# =*= License: GPL-3+ =*=
+
+import os
+
+import cliapp
+
+import vmdb
+
+
+class FstabPlugin(cliapp.Plugin):
+
+    def enable(self):
+        self.app.step_runners.add(FstabStepRunner())
+
+
+class FstabStepRunner(vmdb.StepRunnerInterface):
+
+    def get_required_keys(self):
+        return ['fstab']
+
+    def run(self, step, setting, state):
+        tag = step['fstab']
+        chroot = state.tags.get_mount_point(tag)
+
+        filesystems = []
+
+        for tag in state.tags.get_tags():
+            device = state.tags.get_dev(tag)
+            mount_point = state.tags.get_target_mount_point(tag)
+            fstype = state.tags.get_fstype(tag)
+            output = vmdb.runcmd(['blkid', '-c', '/dev/null', '-o', 'value', '-s', 'UUID', device])
+            if output:
+                uuid = output.decode().strip()
+                filesystems.append({
+                    'uuid': uuid,
+                    'mount_point': mount_point,
+                    'fstype': fstype,
+                })
+            else:
+                raise Exception('Unknown UUID for device {} (to be mounted on {})'.format(device, mount_point))
+
+        fstab_path = os.path.join(chroot, 'etc/fstab')
+        line = "UUID={uuid} {mount_point} {fstype} errors=remount-ro 0 1\n"
+        with open(fstab_path, 'w') as fstab:
+            for entry in filesystems:
+                fstab.write(line.format(**entry))
diff --git a/without-tests b/without-tests
index eb3c686..d15cfe3 100644
--- a/without-tests
+++ b/without-tests
@@ -11,6 +11,7 @@ vmdb/plugins/chroot_plugin.py
 vmdb/plugins/debootstrap_plugin.py
 vmdb/plugins/echo_plugin.py
 vmdb/plugins/error_plugin.py
+vmdb/plugins/fstab_plugin.py
 vmdb/plugins/grub_plugin.py
 vmdb/plugins/kernel_plugin.py
 vmdb/plugins/lvm2_plugin.py