Allow libexec for hotplug (#1088)

When we added the install hotplug module, we forgot to update the
redhet/cloud-init.spec.in file and allow for execution on /usr/libexec.
This PR adds that functionality.

4 files changed, 24 insertions, 17 deletions

diff --git a/cloudinit/config/cc_install_hotplug.py b/cloudinit/config/cc_install_hotplug.py
index d6b2a2df..da98c409 100644
--- a/cloudinit/config/cc_install_hotplug.py
+++ b/cloudinit/config/cc_install_hotplug.py
@@ -85,11 +85,11 @@ __doc__ = get_schema_doc(schema)
 
 
 HOTPLUG_UDEV_PATH = "/etc/udev/rules.d/10-cloud-init-hook-hotplug.rules"
-HOTPLUG_UDEV_RULES = """\
+HOTPLUG_UDEV_RULES_TEMPLATE = """\
 # Installed by cloud-init due to network hotplug userdata
 ACTION!="add|remove", GOTO="cloudinit_end"
 LABEL="cloudinit_hook"
-SUBSYSTEM=="net", RUN+="/usr/lib/cloud-init/hook-hotplug"
+SUBSYSTEM=="net", RUN+="{libexecdir}/hook-hotplug"
 LABEL="cloudinit_end"
 """
 
@@ -129,8 +129,12 @@ def handle(_name, cfg, cloud, log, _args):
         log.debug("Skipping hotplug install, udevadm not found")
         return
 
+    # This may need to turn into a distro property at some point
+    libexecdir = "/usr/libexec/cloud-init"
+    if not os.path.exists(libexecdir):
+        libexecdir = "/usr/lib/cloud-init"
     util.write_file(
         filename=HOTPLUG_UDEV_PATH,
-        content=HOTPLUG_UDEV_RULES,
+        content=HOTPLUG_UDEV_RULES_TEMPLATE.format(libexecdir=libexecdir),
     )
     subp.subp(["udevadm", "control", "--reload-rules"])
diff --git a/cloudinit/sources/__init__.py b/cloudinit/sources/__init__.py
index d61d280d..f2f2343c 100644
--- a/cloudinit/sources/__init__.py
+++ b/cloudinit/sources/__init__.py
@@ -196,6 +196,7 @@ class DataSource(CloudInitPickleMixin, metaclass=abc.ABCMeta):
         EventType.BOOT_NEW_INSTANCE,
         EventType.BOOT,
         EventType.BOOT_LEGACY,
+        EventType.HOTPLUG,
     }}
     default_update_events = {EventScope.NETWORK: {
         EventType.BOOT_NEW_INSTANCE,
diff --git a/packages/redhat/cloud-init.spec.in b/packages/redhat/cloud-init.spec.in
index 22db4b50..1491822b 100644
--- a/packages/redhat/cloud-init.spec.in
+++ b/packages/redhat/cloud-init.spec.in
@@ -119,12 +119,6 @@ version_pys=$(cd "$RPM_BUILD_ROOT" && find . -name version.py -type f)
 ( cd "$RPM_BUILD_ROOT" &&
   sed -i "s,@@PACKAGED_VERSION@@,%{version}-%{release}," $version_pys )
 
-# patch hotplug /usr/libexec script path
-hotplug_file=$(cd "$RPM_BUILD_ROOT" && find . -name 10-cloud-init-hook-hotplug.rules -type f)
-
-( cd "$RPM_BUILD_ROOT" &&
-  sed -i "s,/usr/lib,%{_libexecdir}," $hotplug_file )
-
 %clean
 rm -rf $RPM_BUILD_ROOT
 
@@ -178,7 +172,6 @@ fi
 %files
 
 /lib/udev/rules.d/66-azure-ephemeral.rules
-/lib/udev/rules.d/10-cloud-init-hook-hotplug.rules
 
 %if "%{init_system}" == "systemd"
 /usr/lib/systemd/system-generators/cloud-init-generator
diff --git a/tests/unittests/test_handler/test_handler_install_hotplug.py b/tests/unittests/test_handler/test_handler_install_hotplug.py
index 19b0cc41..5d6b1e77 100644
--- a/tests/unittests/test_handler/test_handler_install_hotplug.py
+++ b/tests/unittests/test_handler/test_handler_install_hotplug.py
@@ -7,7 +7,7 @@ import pytest
 from cloudinit.config.cc_install_hotplug import (
     handle,
     HOTPLUG_UDEV_PATH,
-    HOTPLUG_UDEV_RULES,
+    HOTPLUG_UDEV_RULES_TEMPLATE,
 )
 from cloudinit.event import EventScope, EventType
 
@@ -38,7 +38,10 @@ def mocks():
 
 
 class TestInstallHotplug:
-    def test_rules_installed_when_supported_and_enabled(self, mocks):
+    @pytest.mark.parametrize('libexec_exists', [True, False])
+    def test_rules_installed_when_supported_and_enabled(
+        self, mocks, libexec_exists
+    ):
         mocks.m_which.return_value = 'udevadm'
         mocks.m_update_enabled.return_value = True
         m_cloud = mock.MagicMock()
@@ -46,11 +49,17 @@ class TestInstallHotplug:
             EventScope.NETWORK: {EventType.HOTPLUG}
         }
 
-        handle(None, {}, m_cloud, mock.Mock(), None)
-        mocks.m_write.assert_called_once_with(
-            filename=HOTPLUG_UDEV_PATH,
-            content=HOTPLUG_UDEV_RULES,
-        )
+        if libexec_exists:
+            libexecdir = "/usr/libexec/cloud-init"
+        else:
+            libexecdir = "/usr/lib/cloud-init"
+        with mock.patch('os.path.exists', return_value=libexec_exists):
+            handle(None, {}, m_cloud, mock.Mock(), None)
+            mocks.m_write.assert_called_once_with(
+                filename=HOTPLUG_UDEV_PATH,
+                content=HOTPLUG_UDEV_RULES_TEMPLATE.format(
+                    libexecdir=libexecdir),
+            )
         assert mocks.m_subp.call_args_list == [mock.call([
             'udevadm', 'control', '--reload-rules',
         ])]