Scheduled reports sent without PDF attachments in Aria Operations for Logs 8.18.6

Products

• VCF Operations
• VMware vRealize Log Insight 8.x

Issue/Introduction

• After upgrading VMware Aria Operations for Logs from version 8.18.4 to 8.18.6, scheduled reports are delivered via email at the expected times, but they do not contain the PDF attachment.
• There is line charts included in Aria Operations for logs dashboard. 
• Below error message is observed in /storage/core/loginsight/var/scheduled_reports.log:
  
  Something went wrong during Pdf generation [/usr/lib/loginsight/application/sbin/generate_chart_pdf.py:446: UserWarning: set_ticklabels() should only be used with a fixed number of ticks, i.e. after set_ticks() or using a FixedLocator.
  ax.set_xticklabels([self.__format_str(label, 28) for label in x])
Traceback (most recent call last):
  File "/usr/lib/loginsight/application/sbin/generate_chart_pdf.py", line 676, in <module>
    path = GenerateCharts(DataParser().parse_json(args.f)).generate()
  File "/usr/lib/loginsight/application/sbin/generate_chart_pdf.py", line 72, in generate
    self.__generate_by_chunks(chunk, axs)
  File "/usr/lib/loginsight/application/sbin/generate_chart_pdf.py", line 180, in __generate_by_chunks
    getattr(
  File "/usr/lib/loginsight/application/sbin/generate_chart_pdf.py", line 334, in _generate_line
    ax.plot(x, y)
  File "/usr/lib/loginsight/application/lib/python/matplotlib/axes/_axes.py", line 1779, in plot
    lines = [*self._get_lines(self, *args, data=data, **kwargs)]
  File "/usr/lib/loginsight/application/lib/python/matplotlib/axes/_base.py", line 296, in __call__
    yield from self._plot_args(
  File "/usr/lib/loginsight/application/lib/python/matplotlib/axes/_base.py", line 483, in _plot_args
    axes.yaxis.update_units(y)
  File "/usr/lib/loginsight/application/lib/python/matplotlib/axis.py", line 1756, in update_units
    default = self.converter.default_units(data, self)
  File "/usr/lib/loginsight/application/lib/python/matplotlib/category.py", line 105, in default_units
    axis.set_units(UnitData(data))
  File "/usr/lib/loginsight/application/lib/python/matplotlib/category.py", line 181, in __init__
    self.update(data)
  File "/usr/lib/loginsight/application/lib/python/matplotlib/category.py", line 214, in update
    for val in OrderedDict.fromkeys(data):
TypeError: unhashable type: 'dict'

Environment

VMware Aria Operations for logs 8.18.6

Cause

A regression in the PDF generation engine in version 8.18.6 prevents the processing of specific Line Chart widgets. When the generator encounters certain data structures within a line chart, it fails with a TypeError, resulting in an empty report delivery.

Resolution

This is a known issue. Engineering is currently working on a formal fix, which is expected to be included in a future patch for Aria Operations for Logs.

Workaround:

To ensure reports are sent with their PDF attachments in the current version, you must modify the dashboard widgets that utilize line charts:

1. Identify the dashboard(s) associated with the failing scheduled report.

2. Locate any Line Chart widgets within those dashboards.

3. Edit the widget and change the visualization type to an alternative format, such as a Bar Chart, Pie Chart, or Table.

4. Save the dashboard and trigger a test report to verify the PDF is successfully attached.

Note: Once the fix is released and applied to your environment, you may revert these widgets back to Line Charts.