Report tool traceback on utf-8 decode

[Eric MacDonald]

Brief Description
-----------------
The Report Tool did a utf-8 UnicodeDecodeError traceback while analyzing a bundle.

Code should have a try/except block in this path.

Severity
--------
Major if it happens.

Steps to Reproduce
------------------
report.py -d <path to bundle>

Expected Behavior
------------------
Report analysis completes without execution error.

Actual Behavior
----------------
Report analysis is incomplete.

Reproducibility
---------------
Seen on one collect bundle.

System Configuration
--------------------
suspect System Controller

Branch/Pull Time/Commit
-----------------------
Any prior to this issue being resolved. June 4th, 2024 time frame.

Last Pass
---------
Tool needs to handle string parsing case better

Timestamp/Logs
--------------
Traceback (most recent call last):
  File "/folk/cgts/tools/report/report.py", line 907, in <module>
    engine.execute(plugins, output_dir)
  File "/folk/cgts/tools/report/execution_engine.py", line 382, in execute
    plugin.state["exclude"]),
  File "/folk/cgts/tools/report/plugin_algs/daemon_failures.py", line 40, in daemon_failures
    data = substring(start, end, daemon_substrings, daemon_files, exclude_list)
  File "/folk/cgts/tools/report/plugin_algs/substring.py", line 59, in substring
    status = _continue(start, end, file)
  File "/folk/cgts/tools/report/plugin_algs/substring.py", line 140, in _continue
    line = f.readline()
  File "/usr/local/lib/python3.6/encodings/ascii.py", line 26, in decode
    return codecs.ascii_decode(input, self.errors)[0]
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 6363: ordinal not in range(128)

Test Activity
-------------
PV

Workaround
----------
Analyze bundle manually.
No easy workaround.
Issue will be fixed soon. Pull new content.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/utilities/+/921081

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/utilities/+/921081
Committed: https://opendev.org/starlingx/utilities/commit/a7c75ad8de4cff920de7fd83752e3fd7cec4e36c
Submitter: "Zuul (22348)"
Branch: master

commit a7c75ad8de4cff920de7fd83752e3fd7cec4e36c
Author: Eric MacDonald <email address hidden>
Date: Mon Jun 3 17:25:50 2024 -0400

    Fix utf-8 decode traceback in the report tool strings algorithm

    This update adds a try or except on UnicodeDecodeError to the
    utf-8 decode case in the _evaluate_substring function of the
    strings algorithm.

    Added a dropped logs file to record a list of logs that fail the utf-8
    conversion. The dropped logs file is stored as dropped_logs in the
    report analysis plugins output folder.

    Test Plan:

    PASS: Verify on collect bundle that exhibited the issue.
    PASS: Verify dropped logs are recorded in new
          report_analysis/plugins/dropped_logs file.
    PASS: Verify no newly introduced pep8 errors or warnings.

    Closes-Bug: 2067952
    Change-Id: I82cecd6bb537a459255467f6ced7e742c5771d97
    Signed-off-by: Eric MacDonald <email address hidden>