Fix state checking via kolla_set_configs

Kolla checks the status of its configurations
using kolla_set_configs --check. However, this
doesn't work for the command block in the config.json
file. This means that if only the command value changes,
but not the config_files block, which is common practice
in Kolla-Ansible btw, the container will not report the
changes.

This is undesirable and important to fix, especially
considering the planned rework of notifiers in
Kolla-Ansible [1].

[1] https://review.opendev.org/c/openstack/kolla-ansible/+/773243/14

Closes-Bug: #2080861
Change-Id: I2a290da38ea34b05ce3da8fb8b39b6252bf2da47

Author: keuko

docker/base/set_configs.py

@@ -57,6 +57,10 @@ class ConfigFileBadState(ExitingException):
     pass
 
 
+class ConfigFileCommandDiffers(ExitingException):
+    pass
+
+
 class ConfigFile(object):
 
     def __init__(self, source, dest, owner=None, perm=None, optional=False,
@@ -414,6 +418,15 @@ def execute_config_strategy(config):
         raise InvalidConfig('KOLLA_CONFIG_STRATEGY is not set properly')
 
 
+def execute_command_check(config):
+    cmd = config.get('command')
+    with open("/run_command", "r") as f:
+        cmd_running = f.read()
+    if cmd != cmd_running:
+        msg = "Running command differs. " + cmd + " != " + cmd_running
+        raise ConfigFileCommandDiffers(msg)
+
+
 def execute_config_check(config):
     for data in config.get('config_files', []):
         config_file = ConfigFile(**data)
@@ -431,6 +444,7 @@ def main():
         config = load_config()
 
         if args.check:
+            execute_command_check(config)
             execute_config_check(config)
         else:
             execute_config_strategy(config)

releasenotes/notes/bug-2080861-a46761ea9e7bbf91.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    Fixed an issue where ``kolla_set_configs --check`` failed to detect
+    changes in the ``command`` block of ``config.json`` file.
+    `LP#2080861 <https://bugs.launchpad.net/bugs/2080861>`__