#### Pre-Submission Checklist - [x] Commit message has the format required by CONTRIBUTING guide - [x] Commits are split per component (core, individual modules, libs, utils, ...) - [x] Each component has a single commit (if not, squash them into one commit) - [x] No commits to README files for modules (changes must be done to docbook files in `doc/` subfolder, the README file is autogenerated)

#### Type Of Change - [x] Small bug fix (non-breaking change which fixes an issue) - [ ] New feature (non-breaking change which adds new functionality) - [ ] Breaking change (fix or feature that would change existing functionality)

#### Checklist: - [x] PR should be backported to stable branches - [x] Tested changes locally - [ ] Related to issue #XXXX (replace XXXX with an open issue number)

#### Description commit a725b4fd224c27d84a9f5623faa5af3c3873a2e5 seems to make the `nats_publish` function require the `reply.topic` parameter required. The change from that commit breaks backward compatibility and forces the configuration to pass a reply.topic. This PR makes the `reply.topic` optional.

You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/3507

-- Commit Summary --

* nats: nats_publish set reply parameter to be optional

-- File Changes --

M src/modules/nats/nats_mod.c (4) M src/modules/nats/nats_mod.h (6) M src/modules/nats/nats_pub.c (39) M src/modules/nats/nats_pub.h (5)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/3507.patch https://github.com/kamailio/kamailio/pull/3507.diff