Debian Patching: Patch Remove fails with stacktrace if patch does not exist

[Jessica Castelino]

Brief Description
-----------------

An attempt to remove a patch that does not exist, causes sw-patch-controller-daemon to die. This error is unreadable as well.
We need better handling in this case.

sudo sw-patch remove BLAH
An internal error has occurred. Please check /var/log/patching.log for details

2023-01-24T21:58:35: sw-patch-controller-daemon[1813]: patch_controller.py(2344): ERROR: An uncaught exception has occurred:
Traceback (most recent call last):
  File "/usr/lib/python3.9/wsgiref/handlers.py", line 137, in run
    self.result = application(self.environ, self.start_response)
  File "/usr/lib/python3/dist-packages/cgcs_patch/api/app.py", line 43, in __call__
    return self.v1(environ, start_response)
  File "/usr/lib/python3/dist-packages/pecan/middleware/recursive.py", line 56, in __call__
    return self.application(environ, start_response)
  File "/usr/lib/python3/dist-packages/pecan/core.py", line 840, in __call__
    return super(Pecan, self).__call__(environ, start_response)
  File "/usr/lib/python3/dist-packages/pecan/core.py", line 683, in __call__
    self.invoke_controller(controller, args, kwargs, state)
  File "/usr/lib/python3/dist-packages/pecan/core.py", line 574, in invoke_controller
    result = controller(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/cgcs_patch/api/controllers/root.py", line 72, in remove
    result = pc.patch_remove_api(list(args), **kwargs)
  File "/usr/lib/python3/dist-packages/cgcs_patch/patch_controller.py", line 1270, in patch_remove_api
    ver = self.patch_data.metadata[patch_id]["sw_version"]
KeyError: 'BLAH'
2023-01-24T21:58:53: sw-patch-controller-daemon[1813]: patch_controller.py(2521): INFO: Detected thread death. Terminating
2023-01-24T21:59:03: sw-patch-controller-daemon[65613]: patch_controller.py(673): INFO: patch_op_counter is: 1
2023-01-24T21:59:03: sw-patch-controller-daemon[65613]: patch_controller.py(2706): INFO: launching
2023-01-24T21:59:03: sw-patch-agent[1808]: patch_agent.py(211): INFO: Handling detailed query

Severity
--------
Minor

Steps to Reproduce
------------------
sw-patch remove <Patch-that-doesn't-exist>

Expected Behavior
------------------
Better error handling and readable error

Actual Behavior
----------------
sw-patch-controller-daemon dies and the error presented is not user friendly

Reproducibility
---------------
Reproducible

System Configuration
--------------------
All

Branch/Pull Time/Commit
-----------------------
24th Jan, 2023

Last Pass
---------
N/A

Timestamp/Logs
--------------
N/A

Test Activity
-------------
Developer Testing

Workaround
----------
N/A

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/update/+/871670

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/update/+/871670
Committed: https://opendev.org/starlingx/update/commit/87bc5039701abae5c4f6fc59bcf246e0dc7a9440
Submitter: "Zuul (22348)"
Branch: master

commit 87bc5039701abae5c4f6fc59bcf246e0dc7a9440
Author: Jessica Castelino <email address hidden>
Date: Tue Jan 24 23:01:39 2023 +0000

    Patch Remove fails with stacktrace if patch does not exist

    An attempt to remove a patch that does not exist, causes
    sw-patch-controller-daemon to die. This commit fixes the
    issue.

    Test Plan:
    Verified that the sw-patch-controller-daemon process is not
    killed after removing a patch that does not exist.

    Closes-Bug: 2003821
    Signed-off-by: Jessica Castelino <email address hidden>
    Change-Id: I49c43aab37608da0e11a78413842bf791b09b2b2