unable to subscribe non-persistent topics via regex

[jimmycxm]

Describe the bug
Java client can subscribe persistent topics via regex, but failed to subscribe non-persistent topics.
After some efforts, I found client calls "/admin/v2/namespaces/{namespaces}/topics?mode=ALL" which can't return non-persistent topics.

To Reproduce
Steps to reproduce the behavior:

1. Create topics like below:
   bin/pulsar-admin topics create non-persistent://goldwind/iothub/prop_data-BZ-FAST-1min-001
   bin/pulsar-admin topics create non-persistent://goldwind/iothub/prop_data-BZ-FAST-1min-002
   bin/pulsar-admin topics create non-persistent://goldwind/iothub/prop_data-BZ-FAST_Metric-1min-001
   bin/pulsar-admin topics create non-persistent://goldwind/iothub/prop_data-BZ-FAST_Metric-1min-002
   bin/pulsar-admin topics create persistent://goldwind/iothub/prop_data-BZ-GRID-1min-001
   bin/pulsar-admin topics create persistent://goldwind/iothub/prop_data-BZ-GRID-1min-002
   bin/pulsar-admin topics create persistent://goldwind/iothub/prop_data-BZ-GRID_SECTION-1min-001
   bin/pulsar-admin topics create persistent://goldwind/iothub/prop_data-BZ-GRID_SECTION-1min-002
2. consumer subscribe to
   Pattern.compile("non-persistent://goldwind/iothub/prop_data-(BZ|IT|MK)-FAST-.*")
3. No topic is subscribed.

Expected behavior
topic below should be matched:
non-persistent://goldwind/iothub/prop_data-BZ-FAST-1min-001
non-persistent://goldwind/iothub/prop_data-BZ-FAST-1min-002
non-persistent://goldwind/iothub/prop_data-BZ-FAST_Metric-1min-001
non-persistent://goldwind/iothub/prop_data-BZ-FAST_Metric-1min-002

Screenshots
Here're the topics.

And no non-persistent topics are returned when calling "admin/v2/namespaces/{namespace}topics?mode=NON_PERSISTENT"

While non-persistent topics are returned when calling "admin/v2/non-persistent/{namespace}"

Desktop (please complete the following information):

• OS: linux 64.

Additional context
Release 2.7.2 ,2.7.3, 2.8.0 got same issue.

[casuallc]

@jimmycxm Keep produce message to the non-persistent topic, do not close connction, then you can subscribe the topic with regex mode.

[jimmycxm]

Thanks @casuallc. It works with your suggestion.