Use labels for virtual media dev in agent ramdisk

rameshg87 · rameshg87 · commit d0d319d65fd7 · 2015-03-12T04:45:52.000Z
This commit changes agent deploy ramdisk to find out
the virtual media device by using labels instead of
looking at the model of block device.  This helps in
finding out the device irrespective of the hardware.

Corresponding Ironic change is
If5b78d9af7048f2631d050ee5ce01ab7a67e2354.

Closes-Bug: 1429340
Change-Id: Ib6cc226dc4fb341d913f707737493c31a3f77152
diff --git a/ironic_python_agent/tests/utils.py b/ironic_python_agent/tests/utils.py
@@ -196,44 +196,78 @@ def test__get_vmedia_device(self, glob_mock, open_mock):
         vmedia_device_returned = utils._get_vmedia_device()
         self.assertEqual('sdc', vmedia_device_returned)
 
+    @mock.patch.object(utils, '_read_params_from_file')
+    @mock.patch.object(os.path, 'exists')
+    @mock.patch.object(os, 'mkdir')
+    @mock.patch.object(utils, 'execute')
+    def test__get_vmedia_params_by_label(self, execute_mock, mkdir_mock,
+                                         exists_mock, read_params_mock):
+        vmedia_mount_point = "/vmedia_mnt"
+
+        null_output = ["", ""]
+        expected_params = {'a': 'b'}
+        read_params_mock.return_value = expected_params
+        exists_mock.return_value = True
+        execute_mock.side_effect = [null_output, null_output]
+
+        returned_params = utils._get_vmedia_params()
+
+        mkdir_mock.assert_called_once_with(vmedia_mount_point)
+        execute_mock.assert_any_call('mount', "/dev/disk/by-label/ir-vfd-dev",
+                                     vmedia_mount_point)
+        read_params_mock.assert_called_once_with("/vmedia_mnt/parameters.txt")
+        exists_mock.assert_called_once_with("/dev/disk/by-label/ir-vfd-dev")
+        execute_mock.assert_any_call('umount', vmedia_mount_point)
+        self.assertEqual(expected_params, returned_params)
+
     @mock.patch.object(utils, '_get_vmedia_device')
     @mock.patch.object(utils, '_read_params_from_file')
+    @mock.patch.object(os.path, 'exists')
     @mock.patch.object(os, 'mkdir')
     @mock.patch.object(utils, 'execute')
-    def test__get_vmedia_params(self, execute_mock, mkdir_mock,
-                                read_params_mock, get_device_mock):
+    def test__get_vmedia_params_by_device(self, execute_mock, mkdir_mock,
+                                          exists_mock, read_params_mock,
+                                          get_device_mock):
         vmedia_mount_point = "/vmedia_mnt"
 
         null_output = ["", ""]
         expected_params = {'a': 'b'}
         read_params_mock.return_value = expected_params
+        exists_mock.return_value = False
         execute_mock.side_effect = [null_output, null_output]
         get_device_mock.return_value = "sda"
 
         returned_params = utils._get_vmedia_params()
 
         mkdir_mock.assert_called_once_with(vmedia_mount_point)
-        execute_mock.assert_any_call('mount', "/dev/sda", vmedia_mount_point)
+        execute_mock.assert_any_call('mount', "/dev/sda",
+                                     vmedia_mount_point)
         read_params_mock.assert_called_once_with("/vmedia_mnt/parameters.txt")
         execute_mock.assert_any_call('umount', vmedia_mount_point)
         self.assertEqual(expected_params, returned_params)
 
     @mock.patch.object(utils, '_get_vmedia_device')
-    def test__get_vmedia_params_cannot_find_dev(self, get_device_mock):
+    @mock.patch.object(os.path, 'exists')
+    def test__get_vmedia_params_cannot_find_dev(self, exists_mock,
+                                                get_device_mock):
         get_device_mock.return_value = None
+        exists_mock.return_value = False
         self.assertRaises(errors.VirtualMediaBootError,
                           utils._get_vmedia_params)
 
     @mock.patch.object(utils, '_get_vmedia_device')
     @mock.patch.object(utils, '_read_params_from_file')
+    @mock.patch.object(os.path, 'exists')
     @mock.patch.object(os, 'mkdir')
     @mock.patch.object(utils, 'execute')
     def test__get_vmedia_params_mount_fails(self, execute_mock,
-                                            mkdir_mock, read_params_mock,
+                                            mkdir_mock, exists_mock,
+                                            read_params_mock,
                                             get_device_mock):
         vmedia_mount_point = "/vmedia_mnt"
 
         expected_params = {'a': 'b'}
+        exists_mock.return_value = True
         read_params_mock.return_value = expected_params
         get_device_mock.return_value = "sda"
 
@@ -243,18 +277,22 @@ def test__get_vmedia_params_mount_fails(self, execute_mock,
                           utils._get_vmedia_params)
 
         mkdir_mock.assert_called_once_with(vmedia_mount_point)
-        execute_mock.assert_any_call('mount', "/dev/sda", vmedia_mount_point)
+        execute_mock.assert_any_call('mount', "/dev/disk/by-label/ir-vfd-dev",
+                                     vmedia_mount_point)
 
     @mock.patch.object(utils, '_get_vmedia_device')
     @mock.patch.object(utils, '_read_params_from_file')
+    @mock.patch.object(os.path, 'exists')
     @mock.patch.object(os, 'mkdir')
     @mock.patch.object(utils, 'execute')
     def test__get_vmedia_params_umount_fails(self, execute_mock, mkdir_mock,
-                                            read_params_mock, get_device_mock):
+                                             exists_mock, read_params_mock,
+                                             get_device_mock):
         vmedia_mount_point = "/vmedia_mnt"
 
         null_output = ["", ""]
         expected_params = {'a': 'b'}
+        exists_mock.return_value = True
         read_params_mock.return_value = expected_params
         get_device_mock.return_value = "sda"
 
@@ -264,7 +302,8 @@ def test__get_vmedia_params_umount_fails(self, execute_mock, mkdir_mock,
         returned_params = utils._get_vmedia_params()
 
         mkdir_mock.assert_called_once_with(vmedia_mount_point)
-        execute_mock.assert_any_call('mount', "/dev/sda", vmedia_mount_point)
+        execute_mock.assert_any_call('mount', "/dev/disk/by-label/ir-vfd-dev",
+                                     vmedia_mount_point)
         read_params_mock.assert_called_once_with("/vmedia_mnt/parameters.txt")
         execute_mock.assert_any_call('umount', vmedia_mount_point)
         self.assertEqual(expected_params, returned_params)
diff --git a/ironic_python_agent/utils.py b/ironic_python_agent/utils.py
@@ -92,12 +92,19 @@ def _get_vmedia_params():
     vmedia_mount_point = "/vmedia_mnt"
     parameters_file = "parameters.txt"
 
-    vmedia_device = _get_vmedia_device()
-    if not vmedia_device:
-        msg = "Unable to find virtual media device"
-        raise errors.VirtualMediaBootError(msg)
+    vmedia_device_file = "/dev/disk/by-label/ir-vfd-dev"
+    if not os.path.exists(vmedia_device_file):
+
+        # TODO(rameshg87): This block of code is there only for compatibility
+        # reasons (so that newer agent can work with older Ironic). Remove
+        # this after Liberty release.
+        vmedia_device = _get_vmedia_device()
+        if not vmedia_device:
+            msg = "Unable to find virtual media device"
+            raise errors.VirtualMediaBootError(msg)
+
+        vmedia_device_file = os.path.join("/dev", vmedia_device)
 
-    vmedia_device_file = os.path.join("/dev", vmedia_device)
     os.mkdir(vmedia_mount_point)
 
     try:
