Add Server Instance Feature

[SimonHoenscheid]

Summary

This PR adds server instances to the module.

Additional Context

• Currently the server_instances define relies on the server class providing a baseline
• instances with different versions are not possible, except for upgrade scenarios (e.g 13 was managed before, 14 is the new managed version)

Related Issues (if any)

[SimonHoenscheid]

I think this looks good at the moment. Can you maybe add an acceptance test to spin up multiple instances?

acceptance test added

[Ramesh7]

The code looks good but need more review from postgres experts.

[smortex]

Looks globally good. I have some concerns about the interface which feels very complex and repetitive but I don't think there is much we can do unfortunately.

[smortex]

This should go in the above profile rather than in Hiera.

[smortex]

These 120 lines of boilerplate are scary 😱

I guess that if it was trivial it would have been done, but just to be sure, we have no way to skip some parameters that feel redundant (e.g. pass a datadir and infer the path to config files, generate the service name based on the instance name, etc)? That would require to change a lot of parameter default values and use the value of previous parameters instead of taking a value directly from params.pp?

[tuxmea]

Can we place the directory names in an array? This would reduce the number of lines.

Another option would be to make use of the dirtree module and the dirtree type/provider inside the instance defined type.
Using dirtree option should be done in a different PR as this will raise different discussion.

[tuxmea]

Here we have to replicate the version in many occasions.
Maybe version should become a hiera data, so it can be reused where needed.
Hardcoding version might make sense, if one is able to install multiple postgresql versions in parallel.

[smortex]

(re-adding this comment because I was not reporting it where I though)

This seems to break the module on all non-linux OS:

root@agrajag /usr/home/romain # facter os
{
  architecture => "amd64",
  family => "FreeBSD",
  hardware => "amd64",
  name => "FreeBSD",
  release => {
    branch => "RC4",
    full => "14.0-RC4",
    major => "14",
    minor => "0"
  }
}
root@agrajag /usr/home/romain # puppet agent -t -E romain --tags Postgresql
[...]
Notice: /Stage[main]/Postgresql::Server::Service/Postgresql::Server::Instance::Service[main]/Anchor[postgresql::server::service::begin::main]: Dependency Postgresql_conf[port_for_instance_main] has failures: true
Notice: /Stage[main]/Postgresql::Server::Service/Postgresql::Server::Instance::Service[main]/Anchor[postgresql::server::service::begin::main]: Dependency Postgresql_conf[password_encryption_for_instance_main] has failures: true
Notice: /Stage[main]/Postgresql::Server::Service/Postgresql::Server::Instance::Service[main]/Anchor[postgresql::server::service::begin::main]: Dependency Postgresql_conf[data_directory_for_instance_main] has failures: true
[...]
Error: Could not find a suitable provider for postgresql_conf