ISSUE-17139: [feature request] C++ and Python client support Dead Letter Topic

[sijie]

Original Issue: apache/pulsar-client-cpp#77

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Motivation

Current C++ and Python clients do not support the dead letter topics.

Dead letter topic serves message redelivery, which is triggered by acknowledgement timeout or negative acknowledgement or retry letter topic .

C++ and Python also do not support acknowledgement-timeout and retry-letter-topic.

Solution

1. You can refer to the implementation of java and this PIP-22.
2. PIP-58, here display retry-letter-topic trigger send to dead letter topic.
3. PIP-124 Need support Create init subscription before sending message to DLQ

Alternatives

Can be first implemented negative-acknowledgement trigger send to dead letter topic, and then implement acknowledgement-timeout and retry-letter-topic.

Anything else?

Reference Java implement PR:

• PIP-22: Dead Letter Topic apache/pulsar#2508
• Support Consumers Set Custom Retry Delay apache/pulsar#6449

Are you willing to submit a PR?

• I'm willing to submit a PR!