Is your feature request related to a problem? Please describe.

Currently all the time related types don't include timezone. Also Pulsar doesn't store any timezone information for both publish time and event time. This makes applications inconvenient on handling date types, specially when integrating Pulsar with popular BI tools.

This master issue is to discuss introducing timezone information for the date types in Pulsar.

1. Timezone in Schema.

Currently all time related types don't store any timezone information. We can do either:

a) introduce new schema type (e.g. timestamp_tz) to support storing timestamp along with timezone information.
or
b) to store timezone information in the schema properties. so we can use schema properties to tell if the messages stores timezone information. we can then store the timezone information in the message headers.

2. Publish Time and Event Time.

Pulsar doesn't store and doesn't provide a method for applications to store timezone information. We can introduce two metadata fields publish_time_tz and event_time_tz to store the timezone information.

Once Pulsar supports timezone information for publish_time and event_time, and support date schemas with timezone. We can improve Pulsar SQL to enable it using the timezone information.