Remove hard-coded path to grub binaries

Use PATH variable to find grub binaries.

Closes-Bug: 1717255

Change-Id: Ic6a2bafdc87e33c4e1c4534fa355f995c824b945
(cherry picked from commit db5272cfea9fa894675690d54b7d042cb3d01df3)

3 files changed, 28 insertions, 20 deletions

diff --git a/ironic_python_agent/extensions/image.py b/ironic_python_agent/extensions/image.py
index 36d8ab9a..2ed2e9fc 100644
--- a/ironic_python_agent/extensions/image.py
+++ b/ironic_python_agent/extensions/image.py
@@ -108,12 +108,14 @@ def _install_grub2(device, root_uuid, efi_system_part_uuid=None):
 
         # Add /bin to PATH variable as grub requires it to find efibootmgr
         # when running in uefi boot mode.
+        # Add /usr/sbin to PATH variable to ensure it is there as we do
+        # not use full path to grub binary anymore.
         path_variable = os.environ.get('PATH', '')
-        path_variable = '%s:/bin' % path_variable
+        path_variable = '%s:/bin:/usr/sbin' % path_variable
 
         # Install grub
         utils.execute('chroot %(path)s /bin/sh -c '
-                      '"/usr/sbin/%(bin)s-install %(dev)s"' %
+                      '"%(bin)s-install %(dev)s"' %
                       {'path': path, 'bin': binary_name, 'dev': device},
                       shell=True, env_variables={'PATH': path_variable})
         # Also run grub-install with --removable, this installs grub to the
@@ -126,13 +128,13 @@ def _install_grub2(device, root_uuid, efi_system_part_uuid=None):
         # prevents NVRAM from being updated.
         if efi_partition:
             utils.execute('chroot %(path)s /bin/sh -c '
-                          '"/usr/sbin/%(bin)s-install %(dev)s --removable"' %
+                          '"%(bin)s-install %(dev)s --removable"' %
                           {'path': path, 'bin': binary_name, 'dev': device},
                           shell=True, env_variables={'PATH': path_variable})
 
         # Generate the grub configuration file
         utils.execute('chroot %(path)s /bin/sh -c '
-                      '"/usr/sbin/%(bin)s-mkconfig -o '
+                      '"%(bin)s-mkconfig -o '
                       '/boot/%(bin)s/grub.cfg"' %
                       {'path': path, 'bin': binary_name}, shell=True,
                       env_variables={'PATH': path_variable})
diff --git a/ironic_python_agent/tests/unit/extensions/test_image.py b/ironic_python_agent/tests/unit/extensions/test_image.py
index 7e7fa59b..12fb375a 100644
--- a/ironic_python_agent/tests/unit/extensions/test_image.py
+++ b/ironic_python_agent/tests/unit/extensions/test_image.py
@@ -87,14 +87,14 @@ class TestImageExtension(test_base.BaseTestCase):
                     mock.call('mount', '-t', 'sysfs', 'none',
                               self.fake_dir + '/sys'),
                     mock.call(('chroot %s /bin/sh -c '
-                              '"/usr/sbin/grub-install %s"' %
+                              '"grub-install %s"' %
                                (self.fake_dir, self.fake_dev)), shell=True,
-                              env_variables={'PATH': '/sbin:/bin'}),
+                              env_variables={'PATH': '/sbin:/bin:/usr/sbin'}),
                     mock.call(('chroot %s /bin/sh -c '
-                               '"/usr/sbin/grub-mkconfig -o '
+                               '"grub-mkconfig -o '
                                '/boot/grub/grub.cfg"' % self.fake_dir),
                               shell=True,
-                              env_variables={'PATH': '/sbin:/bin'}),
+                              env_variables={'PATH': '/sbin:/bin:/usr/sbin'}),
                     mock.call('umount', self.fake_dir + '/dev',
                               attempts=3, delay_on_retry=True),
                     mock.call('umount', self.fake_dir + '/proc',
@@ -132,18 +132,18 @@ class TestImageExtension(test_base.BaseTestCase):
                     mock.call('mount', self.fake_efi_system_part,
                               self.fake_dir + '/boot/efi'),
                     mock.call(('chroot %s /bin/sh -c '
-                              '"/usr/sbin/grub-install %s"' %
+                              '"grub-install %s"' %
                                (self.fake_dir, self.fake_dev)), shell=True,
-                              env_variables={'PATH': '/sbin:/bin'}),
+                              env_variables={'PATH': '/sbin:/bin:/usr/sbin'}),
                     mock.call(('chroot %s /bin/sh -c '
-                              '"/usr/sbin/grub-install %s --removable"' %
+                              '"grub-install %s --removable"' %
                                (self.fake_dir, self.fake_dev)), shell=True,
-                              env_variables={'PATH': '/sbin:/bin'}),
+                              env_variables={'PATH': '/sbin:/bin:/usr/sbin'}),
                     mock.call(('chroot %s /bin/sh -c '
-                               '"/usr/sbin/grub-mkconfig -o '
+                               '"grub-mkconfig -o '
                                '/boot/grub/grub.cfg"' % self.fake_dir),
                               shell=True,
-                              env_variables={'PATH': '/sbin:/bin'}),
+                              env_variables={'PATH': '/sbin:/bin:/usr/sbin'}),
                     mock.call('umount', self.fake_dir + '/boot/efi',
                               attempts=3, delay_on_retry=True),
                     mock.call('umount', self.fake_dir + '/dev',
@@ -192,18 +192,18 @@ class TestImageExtension(test_base.BaseTestCase):
                     mock.call('mount', self.fake_efi_system_part,
                               self.fake_dir + '/boot/efi'),
                     mock.call(('chroot %s /bin/sh -c '
-                              '"/usr/sbin/grub-install %s"' %
+                              '"grub-install %s"' %
                                (self.fake_dir, self.fake_dev)), shell=True,
-                              env_variables={'PATH': '/sbin:/bin'}),
+                              env_variables={'PATH': '/sbin:/bin:/usr/sbin'}),
                     mock.call(('chroot %s /bin/sh -c '
-                              '"/usr/sbin/grub-install %s --removable"' %
+                              '"grub-install %s --removable"' %
                                (self.fake_dir, self.fake_dev)), shell=True,
-                              env_variables={'PATH': '/sbin:/bin'}),
+                              env_variables={'PATH': '/sbin:/bin:/usr/sbin'}),
                     mock.call(('chroot %s /bin/sh -c '
-                               '"/usr/sbin/grub-mkconfig -o '
+                               '"grub-mkconfig -o '
                                '/boot/grub/grub.cfg"' % self.fake_dir),
                               shell=True,
-                              env_variables={'PATH': '/sbin:/bin'}),
+                              env_variables={'PATH': '/sbin:/bin:/usr/sbin'}),
                     mock.call('umount', self.fake_dir + '/boot/efi',
                               attempts=3, delay_on_retry=True)]
         mock_execute.assert_has_calls(expected)
diff --git a/releasenotes/notes/fix-hardcoded-path-to-grub-7006f29a9ef72e75.yaml b/releasenotes/notes/fix-hardcoded-path-to-grub-7006f29a9ef72e75.yaml
new file mode 100644
index 00000000..42b20c7a
--- /dev/null
+++ b/releasenotes/notes/fix-hardcoded-path-to-grub-7006f29a9ef72e75.yaml
@@ -0,0 +1,6 @@
+---
+fixes:
+  - Uses the PATH environment variable to get the grub (or grub2)
+    binary instead of assuming it is in /usr/sbin. This provides
+    flexibilty for grub to be installed in any PATH directory,
+    on a partitioned image.