Resolve symlinks in get_devices().

hooks/ceph_hooks.py

@@ -218,7 +218,9 @@ def reformat_osd():
 
 def get_devices():
     if config('osd-devices'):
-        return config('osd-devices').split(' ')
+        return [
+            os.path.realpath(path)
+            for path in config('osd-devices').split(' ')]
     else:
         return []
 

unit_tests/test_config.py

@@ -0,0 +1,59 @@
+import os.path
+import shutil
+import tempfile
+
+import test_utils
+
+import ceph_hooks as hooks
+
+TO_PATCH = [
+    'config',
+]
+
+
+
+class GetDevicesTestCase(test_utils.CharmTestCase):
+
+    def setUp(self):
+        super(GetDevicesTestCase, self).setUp(hooks, TO_PATCH)
+        self.config.side_effect = self.test_config.get
+        self.tmp_dir = tempfile.mkdtemp()
+        self.addCleanup(shutil.rmtree, self.tmp_dir)
+
+    def test_get_devices_empty(self):
+        """
+        If osd-devices is set to an empty string, get_devices() returns
+        an empty list.
+        """
+        self.test_config.set("osd-devices", "")
+        self.assertEqual([], hooks.get_devices())
+
+    def test_get_devices_non_existing_files(self):
+        """
+        If osd-devices points to a file that doesn't exist, it's still
+        returned by get_devices().
+        """
+        non_existing = os.path.join(self.tmp_dir, "no-such-file")
+        self.test_config.set("osd-devices", non_existing)
+        self.assertEqual([non_existing], hooks.get_devices())
+
+    def test_get_devices_multiple(self):
+        """
+        Multiple devices can be specified in osd-devices by separating
+        them with spaces.
+        """
+        device1 = os.path.join(self.tmp_dir, "device1")
+        device2 = os.path.join(self.tmp_dir, "device2")
+        self.test_config.set("osd-devices", "{} {}".format(device1, device2))
+        self.assertEqual([device1, device2], hooks.get_devices())
+
+    def test_get_devices_symlink(self):
+        """
+        If a symlink is specified in osd-devices, get_devices() resolves
+        it and returns the link target.
+        """
+        device = os.path.join(self.tmp_dir, "device")
+        link = os.path.join(self.tmp_dir, "link")
+        os.symlink(device, link)
+        self.test_config.set("osd-devices", link)
+        self.assertEqual([device], hooks.get_devices())